diff --git a/.bazelignore b/.bazelignore
index 30f1613..69c04b1 100644
--- a/.bazelignore
+++ b/.bazelignore
@@ -1 +1,2 @@
 eclipse-out
+node_modules
diff --git a/Documentation/cmd-index.txt b/Documentation/cmd-index.txt
index edb54b5..c991a2a 100644
--- a/Documentation/cmd-index.txt
+++ b/Documentation/cmd-index.txt
@@ -178,6 +178,9 @@
 link:cmd-set-account.html[gerrit set-account]::
 	Change an account's settings.
 
+link:cmd-sequence-show.html[gerrit sequence show]::
+        Display current sequence value.
+
 link:cmd-set-members.html[gerrit set-members]::
 	Set group members.
 
diff --git a/Documentation/cmd-sequence-set.txt b/Documentation/cmd-sequence-set.txt
new file mode 100644
index 0000000..9023ceb
--- /dev/null
+++ b/Documentation/cmd-sequence-set.txt
@@ -0,0 +1,54 @@
+= gerrit sequence set
+
+== NAME
+gerrit sequence set - Set new sequence value.
+
+== SYNOPSIS
+[verse]
+--
+_ssh_ -p <port> <host> _gerrit sequence set_ <NAME> <VALUE>
+--
+
+== DESCRIPTION
+Gerrit maintains the generation of the next available sequence numbers for
+account, group and change entities. The sequences are stored as UTF-8 text in
+a blob pointed to by the `refs/sequences/accounts`, `refs/sequences/groups`
+and `refs/sequences/changes` refs. Those refs are stored in `All-Users` and
+`All-Projects` git repositories correspondingly.
+
+This command allows to set a new sequence value for those sequences.
+
+The link:cmd-sequence-show.html[sequence-show] command displays current
+sequence value.
+
+== ACCESS
+Caller must be a member of the privileged 'Administrators' group.
+
+== SCRIPTING
+This command is intended to be used in scripts.
+
+== OPTIONS
+<NAME>::
+  Sequence name to set a new value for.
+  Currently supported values:
+    * accounts
+    * groups
+    * changes
+
+<VALUE>::
+  New value for the sequence.
+
+== EXAMPLES
+Set a new value for the 'changes' sequence:
+
+----
+$ ssh -p 29418 review.example.com gerrit sequence set changes 42
+The value for the changes sequence was set to 42.
+----
+
+GERRIT
+------
+Part of link:index.html[Gerrit Code Review]
+
+SEARCHBOX
+---------
diff --git a/Documentation/cmd-sequence-show.txt b/Documentation/cmd-sequence-show.txt
new file mode 100644
index 0000000..6b9371f
--- /dev/null
+++ b/Documentation/cmd-sequence-show.txt
@@ -0,0 +1,51 @@
+= gerrit sequence show
+
+== NAME
+gerrit sequence show - Display current sequence value.
+
+== SYNOPSIS
+[verse]
+--
+_ssh_ -p <port> <host> _gerrit sequence show_ <NAME>
+--
+
+== DESCRIPTION
+Gerrit maintains the generation of the next available sequence numbers for
+account, group and change entities. The sequences are stored as UTF-8 text in
+a blob pointed to by the `refs/sequences/accounts`, `refs/sequences/groups`
+and `refs/sequences/changes` refs. Those refs are stored in `All-Users` and
+`All-Projects` git repositories correspondingly.
+
+This command allows to display the current sequence value for those sequences.
+
+The link:cmd-sequence-set.html[sequence-set] command allows to set a new
+sequence value.
+
+== ACCESS
+Caller must be a member of the privileged 'Administrators' group.
+
+== SCRIPTING
+This command is intended to be used in scripts.
+
+== OPTIONS
+<NAME>::
+  Sequence name to show the current value for.
+  Currently supported values:
+    * accounts
+    * groups
+    * changes
+
+== EXAMPLES
+Display the current value for the 'changes' sequence:
+
+----
+$ ssh -p 29418 review.example.com gerrit sequence show changes
+42
+----
+
+GERRIT
+------
+Part of link:index.html[Gerrit Code Review]
+
+SEARCHBOX
+---------
diff --git a/Documentation/config-gerrit.txt b/Documentation/config-gerrit.txt
index 6dd01fe..0ad6905 100644
--- a/Documentation/config-gerrit.txt
+++ b/Documentation/config-gerrit.txt
@@ -2666,6 +2666,28 @@
 	filterClass = org.anyorg.MySecureIPFilter
 ----
 
+[[filterClass.className.initParam]]filterClass.<className>.initParam::
++
+Gerrit supports customized pluggable HTTP filters as `filterClass`. This
+option allows to pass extra initialization parameters to the filter. It
+allows for multiple key/value pairs to be passed in this pattern:
++
+----
+initParam = <key>=<value>
+----
+For a comprehensive example:
++
+----
+[httpd]
+	filterClass = org.anyorg.AFilter
+	filterClass = org.anyorg.BFilter
+[filterClass "org.anyorg.AFilter"]
+	key1 = value1
+	key2 = value2
+[filterClass "org.anyorg.BFilter"]
+	key3 = value3
+----
+
 [[httpd.idleTimeout]]httpd.idleTimeout::
 +
 Maximum idle time for a connection, which roughly translates to the
@@ -2744,6 +2766,22 @@
 If not set or set to a zero, defaults to the number of logical CPUs as returned
 by the JVM. If set to a negative value, defaults to a direct executor.
 
+[[index.change.indexMergeable]]index.change.indexMergeable::
++
+Specifies if `mergeable` should be index or not. Indexing this field enables
+queries that contain the mergeability operator (`is:mergeable`). If enabled,
+Gerrit will check if the change is mergeable into the target branch when
+reindexing a change. This is an expensive operation.
++
+If true, Gerrit will reindex all open changes when the target ref advances.
+Depending on the frequency of updates to the ref and the number of open changes,
+this can be very expensive.
++
+When this setting is changed from `false` to `true`, all changes need to be
+reindexed.
++
+Defaults to true.
+
 [[index.onlineUpgrade]]index.onlineUpgrade::
 +
 Whether to upgrade to new index schema versions while the server is
@@ -2791,19 +2829,6 @@
 +
 Defaults to 1024.
 
-[[index.reindexAfterRefUpdate]]index.reindexAfterRefUpdate::
-+
-Whether to reindex all affected open changes after a ref is updated. This
-includes reindexing all open changes to recompute the "mergeable" bit every time
-the destination branch moves, as well as reindexing changes to take into account
-new project configuration (e.g. label definitions).
-+
-Leaving this enabled may result in fresher results, but may cause performance
-problems if there are lots of open changes on a project whose branches advance
-frequently.
-+
-Defaults to true.
-
 [[index.autoReindexIfStale]]index.autoReindexIfStale::
 +
 Whether to automatically check if a document became stale in the index
@@ -3594,6 +3619,39 @@
 +
 Default is false.
 
+[[operator-alias]]
+=== Section operator alias
+
+Operator aliasing allows global aliases to be defined for query operators.
+Currently only change queries are supported. The alias name is the git
+config key name, and the operator being aliased is the git config value.
+
+For example:
+
+----
+[operator-alias "change"]
+  oldage = age
+  number = change
+----
+
+This section is particularly useful to alias operator names which may be
+long and clunky because they include a plugin name in them to a shorter
+name without the plugin name.
+
+Aliases are resolved dynamically at invocation time to any currently
+loaded versions of plugins. If the alias points to an operator provided
+by a plugin which is not currently loaded, or the plugin does not define
+the operator, then "unsupported operator" is returned to the user.
+
+Aliases will override existing operators. In the case of multiple aliases
+with the same name, the last one defined will be used.
+
+When the target of an alias doesn't exist, the operator with the name
+of the alias will be used (if present). This enables an admin to config
+the system to override a core operator with an operator provided by a
+plugin when present and otherwise fall back to the operator provided by
+core.
+
 [[pack]]
 === Section pack
 
@@ -3748,6 +3806,19 @@
 +
 Default is true.
 
+[[receive.enableInMemoryRefCache]]receive.enableInMemoryRefCache::
++
+If true, Gerrit will cache all refs advertised during push in memory and
+base later receive operations on that cache.
++
+Turning this cache off is considered experimental.
++
+This cache provides value when the ref database is slow and/or does not
+offer an inverse lookup of object ID to ref name. When RefTable is used,
+this cache can be turned off (experimental) to get speed improvements.
++
+Default is true.
+
 [[receive.enableSignedPush]]receive.enableSignedPush::
 +
 If true, server-side signed push validation is enabled.
diff --git a/Documentation/config-plugins.txt b/Documentation/config-plugins.txt
index edeec54..af00d1c 100644
--- a/Documentation/config-plugins.txt
+++ b/Documentation/config-plugins.txt
@@ -37,11 +37,9 @@
 [[core-plugins]]
 == Core Plugins
 
-Core plugins are packaged within the Gerrit war file and can easily be
-installed during the link:pgm-init.html[Gerrit initialization].
-
-The core plugins are developed and maintained by the Gerrit maintainers
-and the Gerrit community.
+link:dev-core-plugins.html[Core plugins] are packaged within the Gerrit
+war file and can easily be installed during the link:pgm-init.html[
+Gerrit initialization].
 
 Note that the documentation and configuration links in the list below are
 to the plugins' master branch. Please refer to the appropriate branch or
diff --git a/Documentation/dev-bazel.txt b/Documentation/dev-bazel.txt
index 3eac4e5..925d399 100644
--- a/Documentation/dev-bazel.txt
+++ b/Documentation/dev-bazel.txt
@@ -32,17 +32,17 @@
 
 `java -version`
 
-[[java-12]]
-==== Java 12 support
+[[java-13]]
+==== Java 13 support
 
-Java 12 (and newer) is supported through vanilla java toolchain
+Java 13 (and newer) is supported through vanilla java toolchain
 link:https://docs.bazel.build/versions/master/toolchains.html[Bazel option].
-To build Gerrit with Java 12 and newer, specify vanilla java toolchain and
+To build Gerrit with Java 13 and newer, specify vanilla java toolchain and
 provide the path to JDK home:
 
 ```
   $ bazel build \
-    --define=ABSOLUTE_JAVABASE=<path-to-java-12> \
+    --define=ABSOLUTE_JAVABASE=<path-to-java-13> \
     --javabase=@bazel_tools//tools/jdk:absolute_javabase \
     --host_javabase=@bazel_tools//tools/jdk:absolute_javabase \
     --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
@@ -55,7 +55,7 @@
 
 ```
   $ bazel test \
-    --define=ABSOLUTE_JAVABASE=<path-to-java-12> \
+    --define=ABSOLUTE_JAVABASE=<path-to-java-13> \
     --javabase=@bazel_tools//tools/jdk:absolute_javabase \
     --host_javabase=@bazel_tools//tools/jdk:absolute_javabase \
     --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla \
@@ -68,7 +68,7 @@
 
 ```
 $ cat << EOF > ~/.bazelrc
-> build --define=ABSOLUTE_JAVABASE=<path-to-java-12>
+> build --define=ABSOLUTE_JAVABASE=<path-to-java-13>
 > build --javabase=@bazel_tools//tools/jdk:absolute_javabase
 > build --host_javabase=@bazel_tools//tools/jdk:absolute_javabase
 > build --host_java_toolchain=@bazel_tools//tools/jdk:toolchain_vanilla
diff --git a/Documentation/dev-core-plugins.txt b/Documentation/dev-core-plugins.txt
new file mode 100644
index 0000000..11027ef
--- /dev/null
+++ b/Documentation/dev-core-plugins.txt
@@ -0,0 +1,94 @@
+= Gerrit Code Review - Core Plugins
+
+[[definition]]
+== What are core plugins?
+
+Core plugins are plugins that are packaged within the Gerrit war file. This
+means during the link:pgm-init.html[Gerrit initialization] they can be easily
+installed without downloading any additional files.
+
+To make working with core plugins easy, they are linked as
+link:https://gerrit.googlesource.com/gerrit/+/refs/heads/master/.gitmodules[Git
+submodules] in the `gerrit` repository. E.g. this means they can be easily
+link:dev-readme.html#clone[cloned] together with Gerrit.
+
+All core plugins are developed and maintained by the
+link:dev-roles.html#maintainers[Gerrit maintainers] and everyone can
+link:dev-contributing.html[contribute] to them.
+
+Adding a new core plugin feature that is large or complex requires a
+link:dev-design-doc.html[design doc] (also see
+link:dev-contributing.html#design-driven-contribution-process[design-driven
+contribution process]). The link:dev-processes.html#steering-committee[
+engineering steering committee (ESC)] is the authority that approves the design
+docs. The ESC is also in charge of adding and removing core plugins.
+
+Non-Gerrit maintainers cannot have link:access-control.html#category_owner[
+Owner] permissions for core plugins.
+
+[[criteria]]
+=== Criteria for Core Plugins
+
+To be considered as a core plugin, a plugin must fulfill the following
+criteria:
+
+1. License:
++
+The plugin code is available under the
+link:http://www.apache.org/licenses/LICENSE-2.0[Apache License Version 2.0].
+
+2. Hosting:
++
+The plugin development is hosted on the
+link:https://gerrit-review.googlesource.com[gerrit-review] Gerrit Server.
+
+3. Scope:
++
+The plugin functionality is Gerrit-related, has a clear scope and does not
+conflict with other core plugins or existing and planned Gerrit core features.
+
+4. Relevance:
++
+The plugin functionality is relevant to a majority of the Gerrit community:
++
+--
+** An out of the box Gerrit installation would seem like it is missing
+   something if the plugin is not installed.
+** It's expected that most sites would use the plugin.
+** Multiple parties (different organizations/companies) already use the plugin
+   and agree that it should be offered as core plugin.
+** If the same or similar functionality is provided by multiple plugins,
+   the plugin is the clear recommended solution by the community.
+--
++
+Whether a plugin is relevant to a majority of the Gerrit community must be
+discussed on a case-by-case basis. In case of doubt, it's up to the
+link:dev-processes.html#steering-committee[engineering steering committee] to
+make a decision.
+
+5. Code Quality:
++
+The plugin code is mature and has a good test coverage. Maintaining the plugin
+code creates only little overhead for the Gerrit maintainers.
+
+6. Documentation:
++
+The plugin functionality is fully documented.
+
+7. Ownership:
++
+Existing plugin owners which are not Gerrit maintainers must agree to give up
+their ownership. If the current plugin owners disagree, forking the plugin is
+possible, but this should happen only in exceptional cases.
+
+[[list]]
+== Which core plugins exist?
+
+See link:config-plugins.html#core-plugins[here].
+
+GERRIT
+------
+Part of link:index.html[Gerrit Code Review]
+
+SEARCHBOX
+---------
diff --git a/Documentation/dev-crafting-changes.txt b/Documentation/dev-crafting-changes.txt
index bf4453c..eb9dee4 100644
--- a/Documentation/dev-crafting-changes.txt
+++ b/Documentation/dev-crafting-changes.txt
@@ -230,6 +230,13 @@
 
   * Tests for new code will greatly help your change get approved.
 
+[[javadoc]]
+== Javadoc
+
+  * Javadocs for new code (especially public classes and
+    public/protected methods) will greatly help your change get
+    approved.
+
 [[change-size]]
 == Change Size/Number of Files Touched
 
diff --git a/Documentation/dev-plugins.txt b/Documentation/dev-plugins.txt
index a2fcd47..b7b807f 100644
--- a/Documentation/dev-plugins.txt
+++ b/Documentation/dev-plugins.txt
@@ -2752,6 +2752,9 @@
 this interface can be used to retry the request instead of failing it
 immediately.
 
+It also allows implementors to group exceptions that have the same
+cause into one metric bucket.
+
 [[mail-soy-template-provider]]
 == MailSoyTemplateProvider
 
diff --git a/Documentation/dev-processes.txt b/Documentation/dev-processes.txt
index f4e77a8..6472f2a 100644
--- a/Documentation/dev-processes.txt
+++ b/Documentation/dev-processes.txt
@@ -7,7 +7,8 @@
 The Gerrit project has an engineering steering committee (ESC) that is
 in charge of:
 
-* Gerrit core (the `gerrit` project) and the core plugins
+* Gerrit core (the `gerrit` project) and the link:dev-core-plugins.html[core
+  plugins]
 * defining the project vision and the project scope
 * maintaining a roadmap, a release plan and a prioritized backlog
 * ensuring timely design reviews
@@ -294,6 +295,11 @@
 vulnerability and define action items to follow up in the
 link:https://bugs.chromium.org/p/gerrit[issue tracker].
 
+[[core-plugins]]
+== Core Plugins
+
+See link:dev-core-plugins.html[here].
+
 [[upgrading-libraries]]
 == Upgrading Libraries
 
diff --git a/Documentation/dev-readme.txt b/Documentation/dev-readme.txt
index 02b1891..34b409c 100644
--- a/Documentation/dev-readme.txt
+++ b/Documentation/dev-readme.txt
@@ -5,6 +5,7 @@
 
 == Git Setup
 
+[[clone]]
 === Getting the Source
 
 Create a new client workspace:
diff --git a/Documentation/intro-gerrit-walkthrough.txt b/Documentation/intro-gerrit-walkthrough.txt
index b4f799c2..a631b47 100644
--- a/Documentation/intro-gerrit-walkthrough.txt
+++ b/Documentation/intro-gerrit-walkthrough.txt
@@ -186,6 +186,7 @@
 
 * Check out the commit
 * Amend the commit
+* Rebase the commit if needed
 * Push the commit to Gerrit
 
 ----
@@ -195,6 +196,20 @@
 [master 30a6f44] Change to a proper, yeast based pizza dough.
  Date: Fri Jun 8 16:28:23 2018 +0200
  1 file changed, 10 insertions(+), 5 deletions(-)
+----
+
+At this point Max wants to make sure that his change is on top of the branch.
+
+----
+$ git fetch
+$
+----
+
+Max got no output from the fetch command, which is good news.
+This means that the master branch has not progressed and there is no need for link:intro-user.html#rebase[*rebase*].
+Max is now ready to push his change:
+
+----
 $ git push origin HEAD:refs/for/master
 Counting objects: 3, done.
 Delta compression using up to 8 threads.
diff --git a/Documentation/licenses.txt b/Documentation/licenses.txt
index 6d4b058..949298f 100644
--- a/Documentation/licenses.txt
+++ b/Documentation/licenses.txt
@@ -65,7 +65,6 @@
 * httpcomponents:httpcore
 * httpcomponents:httpcore-nio
 * jackson:jackson-core
-* jetty:continuation
 * jetty:http
 * jetty:io
 * jetty:jmx
@@ -89,6 +88,8 @@
 * openid:xerces
 * polymer_externs:polymer_closure
 * blame-cache
+* caffeine
+* caffeine-guava
 * gson
 * guava
 * guava-failureaccess
diff --git a/Documentation/rest-api-changes.txt b/Documentation/rest-api-changes.txt
index 09ec415..0fc733a 100644
--- a/Documentation/rest-api-changes.txt
+++ b/Documentation/rest-api-changes.txt
@@ -315,6 +315,11 @@
 the `mergeable` field will always be omitted and `SKIP_MERGEABLE` has no
 effect.
 +
+When link:config-gerrit.html#index.change.indexMergeable[
+`index.change.indexMergeable`] is set to `false` in the `gerrit.config`,
+the `mergeable` field will always be omitted when querying changes and
+`SKIP_MERGEABLE` has no effect.
++
 A change's mergeability can be requested separately by calling the
 link:#get-mergeable[get-mergeable] endpoint.
 --
@@ -1501,6 +1506,90 @@
   change is new
 ----
 
+[[revert-submission]]
+=== Revert Submission
+--
+'POST /changes/link:#change-id[\{change-id\}]/revert_submission'
+--
+
+Creates open revert changes for all of the changes of a certain submission.
+
+Details for the revert can be specified in the request body inside a link:#revert-input[
+RevertInput] The topic of all created revert changes will be
+`revert-{submission_id}-{random_string_of_size_10}`.
+
+The changes will not be rebased on onto the destination branch so the users may still
+have to manually rebase them to resolve conflicts and make them submittable.
+
+.Request
+----
+  POST /changes/myProject~master~I1ffe09a505e25f15ce1521bcfb222e51e62c2a14/revert_submission HTTP/1.0
+----
+
+As response link:#revert-submission-info[RevertSubmissionInfo] entity
+is returned. That entity describes the revert changes.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  "revert_changes":
+    [
+      {
+        "id": "myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940",
+        "project": "myProject",
+        "branch": "master",
+        "topic": "revert--1571043962462-3640749-ABCEEZGHIJ",
+        "change_id": "I8473b95934b5732ac55d26311a706c9c2bde9940",
+        "subject": "Revert \"Implementing Feature X\"",
+        "status": "NEW",
+        "created": "2013-02-01 09:59:32.126000000",
+        "updated": "2013-02-21 11:16:36.775000000",
+        "mergeable": true,
+        "insertions": 6,
+        "deletions": 4,
+        "_number": 3965,
+        "owner": {
+          "name": "John Doe"
+        }
+      },
+      {
+        "id": "anyProject~master~1eee2c9d8f352483781e772f35dc586a69ff5646",
+        "project": "anyProject",
+        "branch": "master",
+        "topic": "revert--1571043962462-3640749-ABCEEZGHIJ",
+        "change_id": "I1eee2c9d8f352483781e772f35dc586a69ff5646",
+        "subject": "Revert \"Implementing Feature Y\"",
+        "status": "NEW",
+        "created": "2013-02-04 09:59:33.126000000",
+        "updated": "2013-02-21 11:16:37.775000000",
+        "mergeable": true,
+        "insertions": 62,
+        "deletions": 11,
+        "_number": 3966,
+        "owner": {
+          "name": "Jane Doe"
+        }
+      }
+    ]
+----
+
+If any of the changes cannot be reverted because the change state doesn't
+allow reverting the change, the response is "`409 Conflict`" and
+the error message is contained in the response body.
+
+.Response
+----
+  HTTP/1.1 409 Conflict
+  Content-Disposition: attachment
+  Content-Type: text/plain; charset=UTF-8
+
+  change is new
+----
+
 [[submit-change]]
 === Submit Change
 --
@@ -5926,6 +6015,8 @@
 When present, change has been marked Ready at some point in time.
 |`revert_of`          |optional|
 The numeric Change-Id of the change that this change reverts.
+|`submission_id`      |optional|
+ID of the submission of this change. Only set if the status is `MERGED`.
 |==================================
 
 [[change-input]]
@@ -6931,10 +7022,24 @@
 Additional information about whom to notify about the revert as a map
 of recipient type to link:#notify-info[NotifyInfo] entity.
 |`topic`         |optional|
-Name of the topic for the revert change. If not set, the default is the topic
-of the change being reverted.
+Name of the topic for the revert change. If not set, the default for Revert
+endpoint is the topic of the change being reverted, and the default for the
+RevertSubmission endpoint is `revert-{submission_id}-{timestamp.now}`.
 |=============================
 
+[[revert-submission-info]]
+=== RevertSubmissionInfo
+The `RevertSubmissionInfo` describes the revert changes.
+
+[options="header",cols="1,6"]
+|==============================
+|Field Name       | Description
+|`revert_changes` |
+A list of link:#change-info[ChangeInfo] that describes the revert changes. Each
+entity in that list is a revert change that was created in that revert
+submission.
+|==============================
+
 [[review-info]]
 === ReviewInfo
 The `ReviewInfo` entity contains information about a review.
diff --git a/Documentation/rest-api-groups.txt b/Documentation/rest-api-groups.txt
index 00fd81f..a99c3bb 100644
--- a/Documentation/rest-api-groups.txt
+++ b/Documentation/rest-api-groups.txt
@@ -341,24 +341,19 @@
 [[query-groups]]
 === Query Groups
 --
-'GET /groups/?query2=<query>'
+'GET /groups/?query=<query>'
 --
 
 Queries internal groups visible to the caller. The
 link:user-search-groups.html#_search_operators[query string] must be
-provided by the `query2` parameter. The `start` and `limit` parameters
+provided by the `query` parameter. The `start` and `limit` parameters
 can be used to skip/limit results.
 
 As result a list of link:#group-info[GroupInfo] entities is returned.
 
-[NOTE] `query2` is a temporary name and in future this option may be
-renamed to `query`. `query2` was chosen to maintain backwards
-compatibility with the deprecated `query` parameter on the
-link:#list-groups[List Groups] endpoint.
-
 .Request
 ----
-  GET /groups/?query2=inname:test HTTP/1.0
+  GET /groups/?query=inname:test HTTP/1.0
 ----
 
 .Response
@@ -398,12 +393,12 @@
 
 [[group-query-limit]]
 ==== Group Limit
-The `/groups/?query2=<query>` URL also accepts a limit integer in the
+The `/groups/?query=<query>` URL also accepts a limit integer in the
 `limit` parameter. This limits the results to `limit` groups.
 
 Query the first 25 groups in group list.
 ----
-  GET /groups/?query2=<query>&limit=25 HTTP/1.0
+  GET /groups/?query=<query>&limit=25 HTTP/1.0
 ----
 
 The `/groups/` URL also accepts a start integer in the `start`
@@ -411,7 +406,7 @@
 
 Query 25 groups starting from index 50.
 ----
-  GET /groups/?query2=<query>&limit=25&start=50 HTTP/1.0
+  GET /groups/?query=<query>&limit=25&start=50 HTTP/1.0
 ----
 
 [[group-query-options]]
diff --git a/Documentation/rest-api-projects.txt b/Documentation/rest-api-projects.txt
index c1349aa..c373b96 100644
--- a/Documentation/rest-api-projects.txt
+++ b/Documentation/rest-api-projects.txt
@@ -2925,6 +2925,374 @@
   HTTP/1.1 204 No Content
 ----
 
+[[label-endpoints]]
+== Label Endpoints
+
+[[list-labels]]
+=== List Labels
+--
+'GET /projects/link:#project-name[\{project-name\}]/labels/'
+--
+
+Lists the labels that are defined in this project.
+
+The calling user must have read access to the `refs/meta/config` branch of the
+project.
+
+.Request
+----
+  GET /projects/All-Projects/labels/ HTTP/1.0
+----
+
+As result a list of link:#label-definition-info[LabelDefinitionInfo] entities
+is returned that describe the labels that are defined in this project
+(inherited labels are not returned unless the `inherited` parameter is set, see
+link:#list-with-inherited-labels[below]). The returned labels are sorted by
+label name.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  [
+    {
+      "name": "Code-Review",
+      "project": "All-Projects",
+      "function": "MaxWithBlock",
+      "values": {
+        " 0": "No score",
+        "-1": "I would prefer this is not merged as is",
+        "-2": "This shall not be merged",
+        "+1": "Looks good to me, but someone else must approve",
+        "+2": "Looks good to me, approved"
+      },
+      "default_value": 0,
+      "can_override": true,
+      "copy_min_score": true,
+      "copy_all_scores_if_no_change": true,
+      "copy_all_scores_on_trivial_rebase": true,
+      "allow_post_submit": true
+    }
+  ]
+----
+
+[[list-with-inherited-labels]]
+To include inherited labels from all parent projects the parameter `inherited`
+can be set.
+
+The calling user must have read access to the `refs/meta/config` branch of the
+project and all its parent projects.
+
+.Request
+----
+  GET /projects/My-Project/labels/?inherited HTTP/1.0
+----
+
+As result a list of link:#label-definition-info[LabelDefinitionInfo] entities
+is returned that describe the labels that are defined in this project and in
+all its parent projects. The returned labels are sorted by parent projects
+in-order from `All-Projects` through the project hierarchy to this project.
+Labels that belong to the same project are sorted by label name.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  [
+    {
+      "name": "Code-Review",
+      "project": "All-Projects",
+      "function": "MaxWithBlock",
+      "values": {
+        " 0": "No score",
+        "-1": "I would prefer this is not merged as is",
+        "-2": "This shall not be merged",
+        "+1": "Looks good to me, but someone else must approve",
+        "+2": "Looks good to me, approved"
+      },
+      "default_value": 0,
+      "can_override": true,
+      "copy_min_score": true,
+      "copy_all_scores_if_no_change": true,
+      "copy_all_scores_on_trivial_rebase": true,
+      "allow_post_submit": true
+    },
+    {
+      "name": "Foo-Review",
+      "project": "My-Project",
+      "function": "MaxWithBlock",
+      "values": {
+        " 0": "No score",
+        "-1": "I would prefer this is not merged as is",
+        "-2": "This shall not be merged",
+        "+1": "Looks good to me, but someone else must approve",
+        "+2": "Looks good to me, approved"
+      },
+      "default_value": 0,
+      "can_override": true,
+      "copy_any_score": true,
+      "allow_post_submit": true
+    }
+  ]
+----
+
+[[get-label]]
+=== Get Label
+--
+'GET /projects/link:#project-name[\{project-name\}]/labels/link:#label-name[\{label-name\}]'
+--
+
+Retrieves the definition of a label that is defined in this project.
+
+The calling user must have read access to the `refs/meta/config` branch of the
+project.
+
+.Request
+----
+  GET /projects/All-Projects/labels/Code-Review HTTP/1.0
+----
+
+As response a link:#label-definition-info[LabelDefinitionInfo] entity is
+returned that describes the label.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "name": "Code-Review",
+    "project": "All-Projects",
+    "function": "MaxWithBlock",
+    "values": {
+      " 0": "No score",
+      "-1": "I would prefer this is not merged as is",
+      "-2": "This shall not be merged",
+      "+1": "Looks good to me, but someone else must approve",
+      "+2": "Looks good to me, approved"
+    },
+    "default_value": 0,
+    "can_override": true,
+    "copy_min_score": true,
+    "copy_all_scores_if_no_change": true,
+    "copy_all_scores_on_trivial_rebase": true,
+    "allow_post_submit": true
+  }
+----
+
+[[create-label]]
+=== Create Label
+--
+'PUT /projects/link:#project-name[\{project-name\}]/labels/link:#label-name[\{label-name\}]'
+--
+
+Creates a new label definition in this project.
+
+The calling user must have write access to the `refs/meta/config` branch of the
+project.
+
+If a label with this name is already defined in this project, this label
+definition is updated (see link:#set-label[Set Label]).
+
+.Request
+----
+  PUT /projects/My-Project/labels/Foo HTTP/1.0
+  Content-Type: application/json; charset=UTF-8
+
+  {
+    "commit_message": "Create Foo Label",
+    "values": {
+      " 0": "No score",
+      "-1": "I would prefer this is not merged as is",
+      "-2": "This shall not be merged",
+      "+1": "Looks good to me, but someone else must approve",
+      "+2": "Looks good to me, approved"
+    }
+  }
+----
+
+As response a link:#label-definition-info[LabelDefinitionInfo] entity is
+returned that describes the created label.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "name": "Foo",
+    "project_name": "My-Project",
+    "function": "MaxWithBlock",
+    "values": {
+      " 0": "No score",
+      "-1": "I would prefer this is not merged as is",
+      "-2": "This shall not be merged",
+      "+1": "Looks good to me, but someone else must approve",
+      "+2": "Looks good to me, approved"
+    },
+    "default_value": 0,
+    "can_override": true,
+    "copy_all_scores_if_no_change": true,
+    "allow_post_submit": true
+  }
+----
+
+[[set-label]]
+=== Set Label
+--
+'PUT /projects/link:#project-name[\{project-name\}]/labels/link:#label-name[\{label-name\}]'
+--
+
+Updates the definition of a label that is defined in this project.
+
+The calling user must have write access to the `refs/meta/config` branch of the
+project.
+
+Properties which are not set in the input entity are not modified.
+
+.Request
+----
+  PUT /projects/All-Projects/labels/Code-Review HTTP/1.0
+  Content-Type: application/json; charset=UTF-8
+
+  {
+    "commit_message": "Ignore self approvals for Code-Review label",
+    "ignore_self_approval": true
+  }
+----
+
+As response a link:#label-definition-info[LabelDefinitionInfo] entity is
+returned that describes the updated label.
+
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "name": "Code-Review",
+    "project": "All-Projects",
+    "function": "MaxWithBlock",
+    "values": {
+      " 0": "No score",
+      "-1": "I would prefer this is not merged as is",
+      "-2": "This shall not be merged",
+      "+1": "Looks good to me, but someone else must approve",
+      "+2": "Looks good to me, approved"
+    },
+    "default_value": 0,
+    "can_override": true,
+    "copy_min_score": true,
+    "copy_all_scores_if_no_change": true,
+    "copy_all_scores_on_trivial_rebase": true,
+    "allow_post_submit": true,
+    "ignore_self_approval": true
+  }
+----
+
+[[delete-label]]
+=== Delete Label
+--
+'DELETE /projects/link:#project-name[\{project-name\}]/labels/link:#label-name[\{label-name\}]'
+--
+
+Deletes the definition of a label that is defined in this project.
+
+The calling user must have write access to the `refs/meta/config` branch of the
+project.
+
+The request body does not need to include a link:#delete-label-input[
+DeleteLabelInput] entity if no commit message is specified.
+
+.Request
+----
+  DELETE /projects/My-Project/labels/Foo-Review HTTP/1.0
+  Content-Type: application/json; charset=UTF-8
+
+  {
+    "commit_message": "Delete Foo-Review label",
+  }
+----
+
+If a label was deleted the response is "`204 No Content`".
+
+.Response
+----
+  HTTP/1.1 204 No Content
+----
+
+[[batch-update-labels]]
+=== Batch Update Labels
+--
+'POST /projects/link:#project-name[\{project-name\}]/labels/'
+--
+
+Creates/updates/deletes multiple label definitions in this project at once.
+
+The calling user must have write access to the `refs/meta/config` branch of the
+project.
+
+The updates must be specified in the request body as
+link:#batch-label-input[BatchLabelInput] entity.
+
+The updates are processed in the following order:
+
+1. label deletions
+2. label creations
+3. label updates
+
+.Request
+----
+  POST /projects/My-Project/labels/ HTTP/1.0
+  Content-Type: application/json; charset=UTF-8
+
+  {
+    "commit_message": "Update Labels",
+    "delete": [
+      "Old-Review",
+      "Unused-Review"
+    ],
+    "create": [
+      {
+        "name": "Foo-Review",
+        "values": {
+          " 0": "No score",
+          "-1": "I would prefer this is not merged as is",
+          "-2": "This shall not be merged",
+          "+1": "Looks good to me, but someone else must approve",
+          "+2": "Looks good to me, approved"
+      }
+    ],
+    "update:" {
+      "Bar-Review": {
+        "function": "MaxWithBlock"
+      },
+      "Baz-Review": {
+        "copy_min_score": true
+      }
+    }
+  }
+----
+
+If the label updates were done successfully the response is "`200 OK`".
+
+.Response
+----
+  HTTP/1.1 200 OK
+----
+
 
 [[ids]]
 == IDs
@@ -2949,6 +3317,10 @@
 A special dashboard ID is `default` which represents the default
 dashboard of a project.
 
+[[label-name]]
+=== \{label-name\}
+The name of a review label.
+
 [[project-name]]
 === \{project-name\}
 The name of the project.
@@ -3122,6 +3494,25 @@
 |`enabled`  |optional|Whether the commentlink is enabled, as documented
 in link:config-gerrit.html#commentlink.name.enabled[
 commentlink.name.enabled]. If not set the commentlink is enabled.
+
+[[commentlink-input]]
+=== CommentLinkInput
+The `CommentLinkInput` entity describes the input for a
+link:config-gerrit.html#commentlink[commentlink].
+
+|==================================================
+[options="header",cols="1,^2,4"]
+|==================================================
+|Field Name |        |Description
+|`match`    |        |A JavaScript regular expression to match
+positions to be replaced with a hyperlink, as documented in
+link:config-gerrit.html#commentlink.name.match[commentlink.name.match].
+|`link`     |        |The URL to direct the user to whenever the
+regular expression is matched, as documented in
+link:config-gerrit.html#commentlink.name.link[commentlink.name.link].
+|`enabled`  |optional|Whether the commentlink is enabled, as documented
+in link:config-gerrit.html#commentlink.name.enabled[
+commentlink.name.enabled]. If not set the commentlink is enabled.
 |==================================================
 
 [[config-info]]
@@ -3272,6 +3663,11 @@
 Whether empty commits should be rejected when a change is merged.
 Can be `TRUE`, `FALSE` or `INHERIT`. +
 If not set, this setting is not updated.
+|commentlinks                              |optional|
+Map of commentlink names to link:#commentlink-input[CommentLinkInput]
+entities to add or update on the project. If the given commentlink
+already exists, it will be updated with the given values, otherwise
+it will be created. If the value is null, that entry is deleted.
 |======================================================
 
 [[config-parameter-info]]
@@ -3309,8 +3705,6 @@
 |`inherited_value` |optional|
 The inherited value of the configuration parameter, only set if
 `inheritable` is true.
-|`permitted_values` |optional|
-The list of permitted values, only set if the `type` is `LIST`.
 |===============================
 
 [[dashboard-info]]
@@ -3377,6 +3771,19 @@
 Tokens such as `${project}` are not resolved.
 |===========================
 
+[[delete-label-input]]
+=== DeleteLabelInput
+The `DeleteLabelInput` entity contains information for deleting a label
+definition in a project.
+
+[options="header",cols="1,^2,4"]
+|=============================
+|Field Name      ||Description
+|`commit_message`|optional|
+Message that should be used to commit the deletion of the label in the
+`project.config` file to the `refs/meta/config` branch.
+|=============================
+
 [[delete-branches-input]]
 === DeleteBranchesInput
 The `DeleteBranchesInput` entity contains information about branches that should
@@ -3459,6 +3866,128 @@
 Not set if there is no parent.
 |================================
 
+[[label-definition-info]]
+=== LabelDefinitionInfo
+The `LabelDefinitionInfo` entity describes a link:config-labels.html[
+review label].
+
+[options="header",cols="1,^2,4"]
+|=============================
+|Field Name      ||Description
+|`name`          ||
+The link:config-labels.html#label_name[name] of the label.
+|`project_name`  ||
+The name of the project in which this label is defined.
+|`function`      ||
+The link:config-labels.html#label_function[function] of the label (can be
+`MaxWithBlock`, `AnyWithBlock`, `MaxNoBlock`, `NoBlock`, `NoOp` and `PatchSetLock`.
+|`values`        ||
+The link:config-labels.html#label_value[values] of the label as a map of label
+value to value description. The label values are formatted strings, e.g. "+1"
+instead of "1", " 0" instead of "0".
+|`default_value` ||
+The link:config-labels.html#label_defaultValue[default value] of the label (as
+integer).
+|`branches`      |optional|
+A list of link:config-labels.html#label_branch[branches] for which the label
+applies. A branch can be a ref, a ref pattern or a regular expression. If not
+set, the label applies for all branches.
+|`can_override`  |`false` if not set|
+Whether this label can be link:config-labels.html#label_canOverride[overridden]
+by child projects.
+|`copy_any_score`|`false` if not set|
+Whether link:config-labels.html#label_copyAnyScore[copyAnyScore] is set on the
+label.
+|`copy_min_score`|`false` if not set|
+Whether link:config-labels.html#label_copyMinScore[copyMinScore] is set on the
+label.
+|`copy_max_score`|`false` if not set|
+Whether link:config-labels.html#label_copyMaxScore[copyMaxScore] is set on the
+label.
+|`copy_all_scores_if_no_change`|`false` if not set|
+Whether link:config-labels.html#label_copyAllScoresIfNoChange[
+copyAllScoresIfNoChange] is set on the label.
+|`copy_all_scores_if_no_code_change`|`false` if not set|
+Whether link:config-labels.html#label_copyAllScoresIfNoCodeChange[
+copyAllScoresIfNoCodeChange] is set on the label.
+|`copy_all_scores_on_trivial_rebase`|`false` if not set|
+Whether link:config-labels.html#label_copyAllScoresOnTrivialRebase[
+copyAllScoresOnTrivialRebase] is set on the label.
+|`copy_all_scores_on_merge_first_parent_update`|`false` if not set|
+Whether link:config-labels.html#label_copyAllScoresOnMergeFirstParentUpdate[
+copyAllScoresOnMergeFirstParentUpdate] is set on the label.
+|`allow_post_submit`|`false` if not set|
+Whether link:config-labels.html#label_allowPostSubmit[allowPostSubmit] is set
+on the label.
+|`ignore_self_approval`|`false` if not set|
+Whether link:config-labels.html#label_ignoreSelfApproval[ignoreSelfApproval] is
+set on the label.
+|=============================
+
+[[label-definition-input]]
+=== LabelDefinitionInput
+The `LabelDefinitionInput` entity describes a link:config-labels.html[
+review label].
+
+[options="header",cols="1,^2,4"]
+|=============================
+|Field Name      ||Description
+|`commit_message`|optional|
+Message that should be used to commit the change of the label in the
+`project.config` file to the `refs/meta/config` branch.+
+Must not be set if this `LabelDefinitionInput` entity is contained in a
+link:#batch-label-input[BatchLabelInput] entity.
+|`name`          |optional|
+The new link:config-labels.html#label_name[name] of the label.+
+For label creation the name is required if this `LabelDefinitionInput` entity
+is contained in a link:#batch-label-input[BatchLabelInput]
+entity.
+|`function`      |optional|
+The new link:config-labels.html#label_function[function] of the label (can be
+`MaxWithBlock`, `AnyWithBlock`, `MaxNoBlock`, `NoBlock`, `NoOp` and `PatchSetLock`.
+|`values`        |optional|
+The new link:config-labels.html#label_value[values] of the label as a map of
+label value to value description. The label values are formatted strings, e.g.
+"+1" instead of "1", " 0" instead of "0".
+|`default_value` |optional|
+The new link:config-labels.html#label_defaultValue[default value] of the label
+(as integer).
+|`branches`      |optional|
+The new branches for which the label applies as a list of
+link:config-labels.html#label_branch[branches]. A branch can be a ref, a ref
+pattern or a regular expression. If not set, the label applies for all
+branches.
+|`can_override`  |optional|
+Whether this label can be link:config-labels.html#label_canOverride[overridden]
+by child projects.
+|`copy_any_score`|optional|
+Whether link:config-labels.html#label_copyAnyScore[copyAnyScore] is set on the
+label.
+|`copy_min_score`|optional|
+Whether link:config-labels.html#label_copyMinScore[copyMinScore] is set on the
+label.
+|`copy_max_score`|optional|
+Whether link:config-labels.html#label_copyMaxScore[copyMaxScore] is set on the
+label.
+|`copy_all_scores_if_no_change`|optional|
+Whether link:config-labels.html#label_copyAllScoresIfNoChange[
+copyAllScoresIfNoChange] is set on the label.
+|`copy_all_scores_if_no_code_change`|optional|
+Whether link:config-labels.html#label_copyAllScoresIfNoCodeChange[
+copyAllScoresIfNoCodeChange] is set on the label.
+|`copy_all_scores_on_trivial_rebase`|optional|
+Whether link:config-labels.html#label_copyAllScoresOnTrivialRebase[
+copyAllScoresOnTrivialRebase] is set on the label.
+|`copy_all_scores_on_merge_first_parent_update`|optional|
+Whether link:config-labels.html#label_copyAllScoresOnMergeFirstParentUpdate[
+copyAllScoresOnMergeFirstParentUpdate] is set on the label.
+|`allow_post_submit`|optional|
+Whether link:config-labels.html#label_allowPostSubmit[allowPostSubmit] is set
+on the label.
+|`ignore_self_approval`|optional|
+Whether link:config-labels.html#label_ignoreSelfApproval[ignoreSelfApproval] is
+set on the label.
+|=============================
 
 [[label-type-info]]
 === LabelTypeInfo
@@ -3495,6 +4024,27 @@
 Not set if not inherited or overridden.
 |===============================
 
+[[batch-label-input]]
+=== BatchLabelInput
+The `BatchLabelInput` entity contains information for batch updating label
+definitions in a project.
+
+[options="header",cols="1,^2,4"]
+|=============================
+|Field Name      ||Description
+|`commit_message`|optional|
+Message that should be used to commit the label updates in the
+`project.config` file to the `refs/meta/config` branch.
+|`delete`        |optional|
+List of labels that should be deleted.
+|`create`        |optional|
+List of link:#label-definition-input[LabelDefinitionInput] entities that
+describe labels that should be created.
+|`update`        |optional|
+Map of label names to link:#label-definition-input[LabelDefinitionInput]
+entities that describe the updates that should be done for the labels.
+|=============================
+
 [[project-access-input]]
 === ProjectAccessInput
 The `ProjectAccessInput` describes changes that should be applied to a project
diff --git a/Documentation/user-search.txt b/Documentation/user-search.txt
index 55a9ab7..bde9508 100644
--- a/Documentation/user-search.txt
+++ b/Documentation/user-search.txt
@@ -140,6 +140,11 @@
 +
 Changes that revert the change specified by the numeric 'ID'.
 
+[[submissionid]]
+submissionid:'ID'::
++
+Changes that have the specified submission 'ID'.
+
 [[reviewerin]]
 reviewerin:'GROUP'::
 +
diff --git a/WORKSPACE b/WORKSPACE
index 3e948c1..e370f69 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -241,6 +241,31 @@
     sha1 = "1dcf1de382a0bf95a3d8b0849546c88bac1292c9",
 )
 
+CAFFEINE_VERS = "2.8.0"
+
+maven_jar(
+    name = "caffeine",
+    artifact = "com.github.ben-manes.caffeine:caffeine:" + CAFFEINE_VERS,
+    sha1 = "6000774d7f8412ced005a704188ced78beeed2bb",
+)
+
+# TODO(davido): Rename guava.jar to caffeine-guava.jar on fetch to prevent potential
+# naming collision between caffeine guava adapater and guava library itself.
+# Remove this renaming procedure, once this upstream issue is fixed:
+# https://github.com/ben-manes/caffeine/issues/364.
+http_file(
+    name = "caffeine-guava-renamed",
+    downloaded_file_path = "caffeine-guava-" + CAFFEINE_VERS + ".jar",
+    sha256 = "3a66ee3ec70971dee0bae6e56bda7b8742bc4bedd7489161bfbbaaf7137d89e1",
+    urls = [
+        "https://repo1.maven.org/maven2/com/github/ben-manes/caffeine/guava/" +
+        CAFFEINE_VERS +
+        "/guava-" +
+        CAFFEINE_VERS +
+        ".jar",
+    ],
+)
+
 maven_jar(
     name = "jsch",
     artifact = "com.jcraft:jsch:0.1.54",
@@ -896,12 +921,6 @@
 )
 
 maven_jar(
-    name = "jetty-continuation",
-    artifact = "org.eclipse.jetty:jetty-continuation:" + JETTY_VERS,
-    sha1 = "3c421a3be5be5805e32b1a7f9c6046526524181d",
-)
-
-maven_jar(
     name = "jetty-http",
     artifact = "org.eclipse.jetty:jetty-http:" + JETTY_VERS,
     sha1 = "c2e73db2db5c369326b717da71b6587b3da11e0e",
diff --git a/contrib/mitm-ui/README.md b/contrib/mitm-ui/README.md
deleted file mode 100644
index 1ec8dd4..0000000
--- a/contrib/mitm-ui/README.md
+++ /dev/null
@@ -1,61 +0,0 @@
-# Scripts for PolyGerrit local development against prod using MitmProxy.
-
-## Installation (OSX)
-
-1. Install Docker from http://docker.com
-2. Start the proxy and create a new proxied browser instance
-   ```
-   cd ~/gerrit
-   ~/mitm-gerrit/mitm-serve-app-dev.sh
-   ```
-3. Make sure that the browser uses the proxy provided by the command line,
-   e.g. if you are a Googler check that the BeyondCorp extension uses the
-   "System/Alternative" proxy.
-4. Install MITM certificates
-   - Open http://mitm.it in the proxied browser window
-   - Follow the instructions to install MITM certs
-
-## Usage
-
-### Add or replace a single plugin containing static content
-
-To develop unminified plugin that loads multiple files, use this.
-
-1. Create a new proxied browser window and start mitmproxy via Docker:
-   ```
-   ~/mitm-gerrit/mitm-single-plugin.sh ./path/to/static/plugin.html
-   ```
-2. Open any *.googlesource.com domain in proxied window
-3. plugin.html and ./path/to/static/* will be served
-
-### Add or replace a minified plugin for *.googlesource.com
-
-This flow assumes no additional .html/.js are needed, i.e. the plugin is a single file.
-
-1. Create a new proxied browser window and start mitmproxy via Docker:
-   ```
-   ~/mitm-gerrit/mitm-plugins.sh ./path/to/plugin.html,./maybe/one/more.js
-   ```
-2. Open any *.googlesource.com domain in proxied window
-3. plugin.html and more.js are served
-
-### Force or replace default site theme for *.googlesource.com
-
-1. Create a new proxied browser window and start mitmproxy via Docker:
-   ```
-   ~/mitm-gerrit/mitm-theme.sh ./path/to/theme.html
-   ```
-2. Open any *.googlesource.com domain in proxied window
-3. Default site themes are enabled.
-4. Local `theme.html` content replaces `/static/gerrit-theme.html`
-5. `/static/*` URLs are served from local theme directory, i.e. `./path/to/`
-
-### Serve uncompiled PolyGerrit
-
-1. Create a new proxied browser window and start mitmproxy via Docker:
-   ```
-   cd ~/gerrit
-   ~/mitm-gerrit/mitm-serve-app-dev.sh
-   ```
-2. Open any *.googlesource.com domain in proxied window
-3. Instead of prod UI (gr-app.html, gr-app.js), local source files will be served
diff --git a/contrib/mitm-ui/add-header.py b/contrib/mitm-ui/add-header.py
deleted file mode 100644
index f9b2b12..0000000
--- a/contrib/mitm-ui/add-header.py
+++ /dev/null
@@ -1,5 +0,0 @@
-# mitmdump -s add-header.py
-def response(flow):
-    if flow.request.host == 'gerrit-review.googlesource.com' and flow.request.path == "/c/92000?1":
-        #flow.response.headers['any'] = '<meta.rdf>; rel=meta'
-        flow.response.headers['Link'] = '</changes/98000/detail?O=11640c>;rel="preload";crossorigin;'
diff --git a/contrib/mitm-ui/dev-chrome.sh b/contrib/mitm-ui/dev-chrome.sh
deleted file mode 100755
index adcb296..0000000
--- a/contrib/mitm-ui/dev-chrome.sh
+++ /dev/null
@@ -1,8 +0,0 @@
-#!/bin/sh
-
-if [[ "$OSTYPE" != "darwin"* ]]; then
-    echo Only works on OSX.
-    exit 1
-fi
-
-/Applications/Google\ Chrome.app/Contents/MacOS/Google\ Chrome --remote-debugging-port=9222 --user-data-dir=${HOME}/devchrome --proxy-server="127.0.0.1:8888"
diff --git a/contrib/mitm-ui/force-version.py b/contrib/mitm-ui/force-version.py
deleted file mode 100644
index a69c885..0000000
--- a/contrib/mitm-ui/force-version.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# mitmdump -q -p 8888 -s "force-version.py --version $1"
-# Request URL is not changed, only the response context
-from mitmproxy import http
-import argparse
-import re
-
-class Server:
-    def __init__(self, version):
-        self.version = version
-
-    def request(self, flow: http.HTTPFlow) -> None:
-        if "gr-app." in flow.request.pretty_url:
-            flow.request.url = re.sub(
-                r"polygerrit_ui/([\d.]+)/elements",
-                "polygerrit_ui/" + self.version + "/elements",
-                flow.request.url)
-
-def start():
-    parser = argparse.ArgumentParser()
-    parser.add_argument("--version", type=str, help="Rapid release version, e.g. 432.0")
-    args = parser.parse_args()
-    return Server(args.version)
diff --git a/contrib/mitm-ui/mitm-docker.sh b/contrib/mitm-ui/mitm-docker.sh
deleted file mode 100755
index a1206f7..0000000
--- a/contrib/mitm-ui/mitm-docker.sh
+++ /dev/null
@@ -1,43 +0,0 @@
-#!/bin/sh
-
-extra_volume='/tmp:/tmp'
-
-POSITIONAL=()
-while [[ $# -gt 0 ]]
-do
-key="$1"
-
-case $key in
-    -v|--volume)
-    extra_volume="$2"
-    shift # past argument
-    shift # past value
-    ;;
-    *)    # unknown option
-    POSITIONAL+=("$1") # save it in an array for later
-    shift # past argument
-    ;;
-esac
-done
-set -- "${POSITIONAL[@]}" # restore positional parameters
-
-if [[ -z "$1" ]]; then
-    echo This is a runner for higher-level scripts, e.g. mitm-serve-app-dev.sh
-    echo Alternatively, pass mitmproxy script from the same dir as a parameter, e.g. serve-app-dev.py
-    exit 1
-fi
-
-gerrit_dir=$(pwd)
-mitm_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
-
-CMD="${mitm_dir}/$1"
-
-docker run --rm -it \
-       -v ~/.mitmproxy:/home/mitmproxy/.mitmproxy \
-       -v ${mitm_dir}:${mitm_dir} \
-       -v ${gerrit_dir}:${gerrit_dir} \
-       -v ${gerrit_dir}/bazel-out:${gerrit_dir}/bazel-out \
-       -v ${extra_volume} \
-       -p 8888:8888 \
-       mitmproxy/mitmproxy:2.0.2 \
-       mitmdump -q -p 8888 -s "${CMD}"
diff --git a/contrib/mitm-ui/mitm-plugins.sh b/contrib/mitm-ui/mitm-plugins.sh
deleted file mode 100755
index fc542bb..0000000
--- a/contrib/mitm-ui/mitm-plugins.sh
+++ /dev/null
@@ -1,39 +0,0 @@
-#!/bin/sh
-
-if [[ -z "$1" ]]; then
-    echo This script injects plugins for *.googlesource.com.
-    echo Provide plugin paths, comma-separated, as a parameter.
-    echo This script assumes files do not have dependencies, i.e. minified.
-    exit 1
-fi
-
-realpath() {
-    [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
-}
-
-join () {
-  local IFS="$1"
-  shift
-  echo "$*"
-}
-
-plugins=$1
-plugin_paths=()
-for plugin in $(echo ${plugins} | sed "s/,/ /g")
-do
-    plugin_paths+=($(realpath ${plugin}))
-done
-
-absolute_plugin_paths=$(join , "${plugin_paths[@]}")
-
-mitm_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
-
-${mitm_dir}/dev-chrome.sh &
-
-bazel build //polygerrit-ui/app:test_components &
-
-${mitm_dir}/mitm-docker.sh \
-           "serve-app-dev.py \
-           --plugins ${absolute_plugin_paths} \
-           --strip_assets \
-           --components $(pwd)/bazel-bin/polygerrit-ui/app/"
diff --git a/contrib/mitm-ui/mitm-serve-app-dev.sh b/contrib/mitm-ui/mitm-serve-app-dev.sh
deleted file mode 100755
index d4c72cc..0000000
--- a/contrib/mitm-ui/mitm-serve-app-dev.sh
+++ /dev/null
@@ -1,15 +0,0 @@
-#!/bin/sh
-
-workspace="./WORKSPACE"
-if [[ ! -f ${workspace} ]] || [[ ! $(head -n 1 ${workspace}) == *"gerrit"* ]]; then
-    echo Please change to cloned Gerrit repo from https://gerrit.googlesource.com/gerrit/
-    exit 1
-fi
-
-mitm_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
-
-bazel build //polygerrit-ui/app:test_components &
-
-${mitm_dir}/dev-chrome.sh &
-
-${mitm_dir}/mitm-docker.sh "serve-app-dev.py --app $(pwd)/polygerrit-ui/app/ --components $(pwd)/bazel-bin/polygerrit-ui/app/"
diff --git a/contrib/mitm-ui/mitm-single-plugin.sh b/contrib/mitm-ui/mitm-single-plugin.sh
deleted file mode 100755
index 8958229..0000000
--- a/contrib/mitm-ui/mitm-single-plugin.sh
+++ /dev/null
@@ -1,38 +0,0 @@
-#!/bin/sh
-
-if [[ -z "$1" ]]; then
-    echo This script serves one plugin with the rest of static content.
-    echo Provide path to index plugin file, e.g. buildbucket.html for buildbucket plugin
-    exit 1
-fi
-
-realpath() {
-  OURPWD=$PWD
-  cd "$(dirname "$1")"
-  LINK=$(basename "$1")
-  while [ -L "$LINK" ]; do
-      LINK=$(readlink "$LINK")
-      cd "$(dirname "$LINK")"
-      LINK="$(basename "$1")"
-  done
-  REAL_DIR=`pwd -P`
-  RESULT=$REAL_DIR/$LINK
-  cd "$OURPWD"
-  echo "$RESULT"
-}
-
-plugin=$(realpath $1)
-plugin_root=$(dirname ${plugin})
-
-mitm_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
-
-${mitm_dir}/dev-chrome.sh &
-
-bazel build //polygerrit-ui/app:test_components &
-
-${mitm_dir}/mitm-docker.sh -v ${plugin_root}:${plugin_root} \
-           "serve-app-dev.py \
-           --plugins ${plugin} \
-           --strip_assets \
-           --plugin_root ${plugin_root}  \
-           --components $(pwd)/bazel-bin/polygerrit-ui/app/"
diff --git a/contrib/mitm-ui/mitm-theme.sh b/contrib/mitm-ui/mitm-theme.sh
deleted file mode 100755
index 9290235..0000000
--- a/contrib/mitm-ui/mitm-theme.sh
+++ /dev/null
@@ -1,31 +0,0 @@
-#!/bin/sh
-
-if [[ -z "$1" ]]; then
-    echo This script forces or replaces default site theme on *.googlesource.com
-    echo Provide path to the theme.html as a parameter.
-    exit 1
-fi
-
-realpath() {
-  OURPWD=$PWD
-  cd "$(dirname "$1")"
-  LINK=$(basename "$1")
-  while [ -L "$LINK" ]; do
-      LINK=$(readlink "$LINK")
-      cd "$(dirname "$LINK")"
-      LINK="$(basename "$1")"
-  done
-  REAL_DIR=`pwd -P`
-  RESULT=$REAL_DIR/$LINK
-  cd "$OURPWD"
-  echo "$RESULT"
-}
-
-theme=$(realpath "$1")
-theme_dir=$(dirname "${theme}")
-
-mitm_dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null && pwd )"
-
-"${mitm_dir}"/dev-chrome.sh &
-
-"${mitm_dir}"/mitm-docker.sh -v "${theme_dir}":"${theme_dir}" "serve-app-dev.py --strip_assets --theme \"${theme}\""
diff --git a/contrib/mitm-ui/serve-app-dev.py b/contrib/mitm-ui/serve-app-dev.py
deleted file mode 100644
index cdf7bfc..0000000
--- a/contrib/mitm-ui/serve-app-dev.py
+++ /dev/null
@@ -1,169 +0,0 @@
-# 1. install and setup mitmproxy v2.0.2: https://mitmproxy.readthedocs.io/en/v2.0.2/install.html
-#   (In case of python versions trouble, use https://www.anaconda.com/)
-# 2. mitmdump -q -s -p 8888 \
-#   "serve-app-dev.py --app /path/to/polygerrit-ui/app/"
-# 3. start Chrome with --proxy-server="127.0.0.1:8888" --user-data-dir=/tmp/devchrome
-# 4. open, say, gerrit-review.googlesource.com. Or chromium-review.googlesource.com. Any.
-# 5. uncompiled source files are served and you can log in, too.
-# 6. enjoy!
-#
-# P.S. For replacing plugins, use --plugins or --plugin_root
-#
-# --plugin takes comma-separated list of plugins to add or replace.
-#
-# Example: Adding a new plugin to the server response:
-# --plugins ~/gerrit-testsite/plugins/myplugin.html
-#
-# Example: Replace all matching plugins with local versions:
-# --plugins ~/gerrit-testsite/plugins/
-# Following files will be served if they exist for /plugins/tricium/static/tricium.html:
-#  ~/gerrit-testsite/plugins/tricium.html
-#  ~/gerrit-testsite/plugins/tricium/static/tricium.html
-#
-# --assets takes assets bundle.html, expecting rest of the assets files to be in the same folder
-#
-# Example:
-#  --assets ~/gerrit-testsite/assets/a3be19f.html
-#
-
-from mitmproxy import http
-from mitmproxy.script import concurrent
-import argparse
-import json
-import mimetypes
-import os.path
-import re
-import zipfile
-
-class Server:
-    def __init__(self, devpath, components, plugins, pluginroot, assets, strip_assets, theme):
-        if devpath:
-            print("Serving app from " + devpath)
-        if components:
-            print("Serving components from " + components)
-        if pluginroot:
-            print("Serving plugins from " + pluginroot)
-        if assets:
-            self.assets_root, self.assets_file = os.path.split(assets)
-            print("Assets: using " + self.assets_file + " from " + self.assets_root)
-        else:
-            self.assets_root = None
-        if plugins:
-            self.plugins = {path.split("/")[-1:][0]: path for path in map(expandpath, plugins.split(","))}
-            for filename, path in self.plugins.items():
-                print("Serving " + filename + " from " + path)
-        else:
-            self.plugins = {}
-        self.devpath = devpath
-        self.components = components
-        self.pluginroot = pluginroot
-        self.strip_assets = strip_assets
-        self.theme = theme
-
-    def readfile(self, path):
-        with open(path, 'rb') as contentfile:
-            return contentfile.read()
-
-@concurrent
-def response(flow: http.HTTPFlow) -> None:
-    if server.strip_assets:
-        assets_bundle = 'googlesource.com/polygerrit_assets'
-        assets_pos = flow.response.text.find(assets_bundle)
-        if assets_pos != -1:
-            t = flow.response.text
-            flow.response.text = t[:t.rfind('<', 0, assets_pos)] + t[t.find('>', assets_pos) + 1:]
-            return
-
-    if server.assets_root:
-        marker = 'webcomponents-lite.js"></script>'
-        pos = flow.response.text.find(marker)
-        if pos != -1:
-            pos += len(marker)
-            flow.response.text = ''.join([
-                flow.response.text[:pos],
-                '<link rel="import" href="/gerrit_assets/123.0/' + server.assets_file + '">',
-                flow.response.text[pos:]
-            ])
-
-        assets_prefix = "/gerrit_assets/123.0/"
-        if flow.request.path.startswith(assets_prefix):
-            assets_file = flow.request.path[len(assets_prefix):]
-            flow.response.content = server.readfile(server.assets_root + '/' + assets_file)
-            flow.response.status_code = 200
-            if assets_file.endswith('.js'):
-                flow.response.headers['Content-type'] = 'text/javascript'
-            return
-    m = re.match(".+polygerrit_ui/\d+\.\d+/(.+)", flow.request.path)
-    pluginmatch = re.match("^/plugins/(.+)", flow.request.path)
-    localfile = ""
-    content = ""
-    if flow.request.path == "/config/server/info":
-        config = json.loads(flow.response.content[5:].decode('utf8'))
-        if server.theme:
-            config['default_theme'] = '/static/gerrit-theme.html'
-        for filename, path in server.plugins.items():
-            pluginname = filename.split(".")[0]
-            payload = config["plugin"]["js_resource_paths" if filename.endswith(".js") else "html_resource_paths"]
-            if list(filter(lambda url: filename in url, payload)):
-                continue
-            payload.append("plugins/" + pluginname + "/static/" + filename)
-        flow.response.content = str.encode(")]}'\n" + json.dumps(config))
-    if m is not None:
-        filepath = m.groups()[0]
-        if (filepath.startswith("bower_components/")):
-            with zipfile.ZipFile(server.components + "test_components.zip") as bower_zip:
-                content = bower_zip.read(filepath)
-        localfile = server.devpath + filepath
-    elif pluginmatch is not None:
-        pluginfile = flow.request.path_components[-1]
-        if server.plugins and pluginfile in server.plugins:
-            if os.path.isfile(server.plugins[pluginfile]):
-                localfile = server.plugins[pluginfile]
-            else:
-                print("Can't find file " + server.plugins[pluginfile] + " for " + flow.request.path)
-        elif server.pluginroot:
-            pluginurl = pluginmatch.groups()[0]
-            if os.path.isfile(server.pluginroot + pluginfile):
-                localfile = server.pluginroot + pluginfile
-            elif os.path.isfile(server.pluginroot + pluginurl):
-                localfile = server.pluginroot + pluginurl
-
-    if server.theme:
-        if flow.request.path.endswith('/gerrit-theme.html'):
-            localfile = server.theme
-        else:
-            match = re.match("^/static(/[\w\.]+)$", flow.request.path)
-            if match is not None:
-                localfile = os.path.dirname(server.theme) + match.group(1)
-
-    if localfile and os.path.isfile(localfile):
-        if pluginmatch is not None:
-            print("Serving " + flow.request.path + " from " + localfile)
-        content = server.readfile(localfile)
-
-    if content:
-        flow.response.content = content
-        flow.response.status_code = 200
-        localtype = mimetypes.guess_type(localfile)
-        if localtype and localtype[0]:
-            flow.response.headers['Content-type'] = localtype[0]
-
-def expandpath(path):
-    return os.path.realpath(os.path.expanduser(path))
-
-parser = argparse.ArgumentParser()
-parser.add_argument("--app", type=str, default="", help="Path to /polygerrit-ui/app/")
-parser.add_argument("--components", type=str, default="", help="Path to test_components.zip")
-parser.add_argument("--plugins", type=str, default="", help="Comma-separated list of plugin files to add/replace")
-parser.add_argument("--plugin_root", type=str, default="", help="Path containing individual plugin files to replace")
-parser.add_argument("--assets", type=str, default="", help="Path containing assets file to import.")
-parser.add_argument("--strip_assets", action="store_true", help="Strip plugin bundles from the response.")
-parser.add_argument("--theme", default="", type=str, help="Path to the default site theme to be used.")
-args = parser.parse_args()
-server = Server(expandpath(args.app) + '/',
-                expandpath(args.components) + '/',
-                args.plugins,
-                expandpath(args.plugin_root) + '/',
-                args.assets and expandpath(args.assets),
-                args.strip_assets,
-                expandpath(args.theme))
diff --git a/contrib/mitm-ui/serve-app-locally.py b/contrib/mitm-ui/serve-app-locally.py
deleted file mode 100644
index 636c684..0000000
--- a/contrib/mitm-ui/serve-app-locally.py
+++ /dev/null
@@ -1,46 +0,0 @@
-# bazel build polygerrit-ui/app:gr-app
-# mitmdump -s "serve-app-locally.py ~/gerrit/bazel-bin/polygerrit-ui/app"
-from mitmproxy import http
-import argparse
-import os
-import zipfile
-
-class Server:
-    def __init__(self, bundle):
-        self.bundle = bundle
-        self.bundlemtime = 0
-        self.files = {
-            'polygerrit_ui/elements/gr-app.js': '',
-            'polygerrit_ui/elements/gr-app.html': '',
-            'polygerrit_ui/styles/main.css': '',
-        }
-        self.read_files()
-
-    def read_files(self):
-        if not os.path.isfile(self.bundle):
-            print("bundle not found!")
-            return
-        mtime = os.stat(self.bundle).st_mtime
-        if mtime <= self.bundlemtime:
-            return
-        self.bundlemtime = mtime
-        with zipfile.ZipFile(self.bundle) as z:
-            for fname in self.files:
-                print('Reading new content for ' + fname)
-                with z.open(fname, 'r') as content_file:
-                    self.files[fname] = content_file.read()
-
-    def response(self, flow: http.HTTPFlow) -> None:
-        self.read_files()
-        for name in self.files:
-            if name.rsplit('/', 1)[1] in flow.request.pretty_url:
-                flow.response.content = self.files[name]
-
-def expandpath(path):
-    return os.path.expanduser(path)
-
-def start():
-    parser = argparse.ArgumentParser()
-    parser.add_argument("bundle", type=str)
-    args = parser.parse_args()
-    return Server(expandpath(args.bundle))
diff --git a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
index 7edb43a..fd61aa5 100644
--- a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
@@ -644,6 +644,14 @@
     return result;
   }
 
+  protected PushOneCommit.Result createChange(TestRepository<InMemoryRepository> repo)
+      throws Exception {
+    PushOneCommit push = pushFactory.create(admin.newIdent(), repo);
+    PushOneCommit.Result result = push.to("refs/for/master");
+    result.assertOkStatus();
+    return result;
+  }
+
   protected PushOneCommit.Result createMergeCommitChange(String ref) throws Exception {
     return createMergeCommitChange(ref, "foo");
   }
diff --git a/java/com/google/gerrit/acceptance/BUILD b/java/com/google/gerrit/acceptance/BUILD
index 812d089..cb3524a 100644
--- a/java/com/google/gerrit/acceptance/BUILD
+++ b/java/com/google/gerrit/acceptance/BUILD
@@ -79,6 +79,7 @@
     ),
     exported_deps = [
         ":function",
+        "//java/com/google/gerrit/acceptance/config",
         "//java/com/google/gerrit/acceptance/testsuite/project",
         "//java/com/google/gerrit/exceptions",
         "//java/com/google/gerrit/gpg",
diff --git a/java/com/google/gerrit/acceptance/GerritServer.java b/java/com/google/gerrit/acceptance/GerritServer.java
index 678bc31..f90df67 100644
--- a/java/com/google/gerrit/acceptance/GerritServer.java
+++ b/java/com/google/gerrit/acceptance/GerritServer.java
@@ -25,6 +25,11 @@
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.gerrit.acceptance.config.ConfigAnnotationParser;
+import com.google.gerrit.acceptance.config.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfigs;
+import com.google.gerrit.acceptance.config.GlobalPluginConfig;
+import com.google.gerrit.acceptance.config.GlobalPluginConfigs;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperationsImpl;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
@@ -264,7 +269,7 @@
 
   private static final ImmutableMap<String, Level> LOG_LEVELS =
       ImmutableMap.<String, Level>builder()
-          .put("com.google.gerrit", Level.DEBUG)
+          .put("com.google.gerrit", getGerritLogLevel())
 
           // Silence non-critical messages from MINA SSHD.
           .put("org.apache.mina", Level.WARN)
@@ -302,6 +307,14 @@
           .put("org.eclipse.jgit.util.FS", Level.WARN)
           .build();
 
+  private static Level getGerritLogLevel() {
+    String value = Strings.nullToEmpty(System.getenv("GERRIT_LOG_LEVEL"));
+    if (value.isEmpty()) {
+      value = Strings.nullToEmpty(System.getProperty("gerrit.logLevel"));
+    }
+    return Level.toLevel(value, Level.INFO);
+  }
+
   private static boolean forceLocalDisk() {
     String value = Strings.nullToEmpty(System.getenv("GERRIT_FORCE_LOCAL_DISK"));
     if (value.isEmpty()) {
@@ -558,8 +571,8 @@
     cfg.setInt("sshd", null, "commandStartThreads", 1);
     cfg.setInt("receive", null, "threadPoolSize", 1);
     cfg.setInt("index", null, "threads", 1);
-    if (cfg.getString("index", null, "reindexAfterRefUpdate") == null) {
-      cfg.setBoolean("index", null, "reindexAfterRefUpdate", false);
+    if (cfg.getString("index", "change", "indexMergeable") == null) {
+      cfg.setBoolean("index", "change", "indexMergeable", false);
     }
   }
 
diff --git a/java/com/google/gerrit/acceptance/config/BUILD b/java/com/google/gerrit/acceptance/config/BUILD
new file mode 100644
index 0000000..a8ccc1f
--- /dev/null
+++ b/java/com/google/gerrit/acceptance/config/BUILD
@@ -0,0 +1,15 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
+package(default_testonly = 1)
+
+java_library(
+    name = "config",
+    srcs = glob(["*.java"]),
+    visibility = ["//visibility:public"],
+    deps = [
+        "//lib:guava",
+        "//lib:jgit",
+        "//lib/auto:auto-value",
+        "//lib/auto:auto-value-annotations",
+    ],
+)
diff --git a/java/com/google/gerrit/acceptance/ConfigAnnotationParser.java b/java/com/google/gerrit/acceptance/config/ConfigAnnotationParser.java
similarity index 89%
rename from java/com/google/gerrit/acceptance/ConfigAnnotationParser.java
rename to java/com/google/gerrit/acceptance/config/ConfigAnnotationParser.java
index 0a1d765..24a2117 100644
--- a/java/com/google/gerrit/acceptance/ConfigAnnotationParser.java
+++ b/java/com/google/gerrit/acceptance/config/ConfigAnnotationParser.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance;
+package com.google.gerrit.acceptance.config;
 
 import com.google.auto.value.AutoAnnotation;
 import com.google.common.base.Splitter;
@@ -24,10 +24,10 @@
 import java.util.Map;
 import org.eclipse.jgit.lib.Config;
 
-class ConfigAnnotationParser {
+public class ConfigAnnotationParser {
   private static Splitter splitter = Splitter.on(".").trimResults();
 
-  static Config parse(Config base, GerritConfigs annotation) {
+  public static Config parse(Config base, GerritConfigs annotation) {
     if (annotation == null) {
       return null;
     }
@@ -39,33 +39,13 @@
     return cfg;
   }
 
-  static Config parse(Config base, GerritConfig annotation) {
+  public static Config parse(Config base, GerritConfig annotation) {
     Config cfg = new Config(base);
     parseAnnotation(cfg, annotation);
     return cfg;
   }
 
-  private static GerritConfig toGerritConfig(GlobalPluginConfig annotation) {
-    return newGerritConfig(annotation.name(), annotation.value(), annotation.values());
-  }
-
-  @AutoAnnotation
-  private static GerritConfig newGerritConfig(String name, String value, String[] values) {
-    return new AutoAnnotation_ConfigAnnotationParser_newGerritConfig(name, value, values);
-  }
-
-  static Map<String, Config> parse(GlobalPluginConfig annotation) {
-    if (annotation == null) {
-      return null;
-    }
-    Map<String, Config> result = new HashMap<>();
-    Config cfg = new Config();
-    parseAnnotation(cfg, toGerritConfig(annotation));
-    result.put(annotation.pluginName(), cfg);
-    return result;
-  }
-
-  static Map<String, Config> parse(GlobalPluginConfigs annotation) {
+  public static Map<String, Config> parse(GlobalPluginConfigs annotation) {
     if (annotation == null || annotation.value().length < 1) {
       return null;
     }
@@ -87,6 +67,26 @@
     return result;
   }
 
+  public static Map<String, Config> parse(GlobalPluginConfig annotation) {
+    if (annotation == null) {
+      return null;
+    }
+    Map<String, Config> result = new HashMap<>();
+    Config cfg = new Config();
+    parseAnnotation(cfg, toGerritConfig(annotation));
+    result.put(annotation.pluginName(), cfg);
+    return result;
+  }
+
+  private static GerritConfig toGerritConfig(GlobalPluginConfig annotation) {
+    return newGerritConfig(annotation.name(), annotation.value(), annotation.values());
+  }
+
+  @AutoAnnotation
+  private static GerritConfig newGerritConfig(String name, String value, String[] values) {
+    return new AutoAnnotation_ConfigAnnotationParser_newGerritConfig(name, value, values);
+  }
+
   private static void parseAnnotation(Config cfg, GerritConfig c) {
     ArrayList<String> l = Lists.newArrayList(splitter.split(c.name()));
     if (l.size() == 2) {
diff --git a/java/com/google/gerrit/acceptance/GerritConfig.java b/java/com/google/gerrit/acceptance/config/GerritConfig.java
similarity index 96%
rename from java/com/google/gerrit/acceptance/GerritConfig.java
rename to java/com/google/gerrit/acceptance/config/GerritConfig.java
index fe0c628..26be2d4 100644
--- a/java/com/google/gerrit/acceptance/GerritConfig.java
+++ b/java/com/google/gerrit/acceptance/config/GerritConfig.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance;
+package com.google.gerrit.acceptance.config;
 
 import static java.lang.annotation.ElementType.METHOD;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
diff --git a/java/com/google/gerrit/acceptance/GerritConfigs.java b/java/com/google/gerrit/acceptance/config/GerritConfigs.java
similarity index 94%
rename from java/com/google/gerrit/acceptance/GerritConfigs.java
rename to java/com/google/gerrit/acceptance/config/GerritConfigs.java
index e0f9d4a..0127ace 100644
--- a/java/com/google/gerrit/acceptance/GerritConfigs.java
+++ b/java/com/google/gerrit/acceptance/config/GerritConfigs.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance;
+package com.google.gerrit.acceptance.config;
 
 import static java.lang.annotation.ElementType.METHOD;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
diff --git a/java/com/google/gerrit/acceptance/GlobalPluginConfig.java b/java/com/google/gerrit/acceptance/config/GlobalPluginConfig.java
similarity index 96%
rename from java/com/google/gerrit/acceptance/GlobalPluginConfig.java
rename to java/com/google/gerrit/acceptance/config/GlobalPluginConfig.java
index 43477ae..ae88e37 100644
--- a/java/com/google/gerrit/acceptance/GlobalPluginConfig.java
+++ b/java/com/google/gerrit/acceptance/config/GlobalPluginConfig.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance;
+package com.google.gerrit.acceptance.config;
 
 import static java.lang.annotation.ElementType.METHOD;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
diff --git a/java/com/google/gerrit/acceptance/GlobalPluginConfigs.java b/java/com/google/gerrit/acceptance/config/GlobalPluginConfigs.java
similarity index 95%
rename from java/com/google/gerrit/acceptance/GlobalPluginConfigs.java
rename to java/com/google/gerrit/acceptance/config/GlobalPluginConfigs.java
index dfcf955..e53e5ba 100644
--- a/java/com/google/gerrit/acceptance/GlobalPluginConfigs.java
+++ b/java/com/google/gerrit/acceptance/config/GlobalPluginConfigs.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance;
+package com.google.gerrit.acceptance.config;
 
 import static java.lang.annotation.ElementType.METHOD;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
diff --git a/java/com/google/gerrit/common/data/LabelType.java b/java/com/google/gerrit/common/data/LabelType.java
index f9cd562..14b8310 100644
--- a/java/com/google/gerrit/common/data/LabelType.java
+++ b/java/com/google/gerrit/common/data/LabelType.java
@@ -157,6 +157,10 @@
     return name;
   }
 
+  public void setName(String name) {
+    this.name = checkName(name);
+  }
+
   public boolean matches(PatchSetApproval psa) {
     return psa.labelId().get().equalsIgnoreCase(name);
   }
@@ -173,6 +177,7 @@
     return canOverride;
   }
 
+  @Nullable
   public List<String> getRefPatterns() {
     return refPatterns;
   }
@@ -198,7 +203,7 @@
   }
 
   public void setRefPatterns(List<String> refPatterns) {
-    if (refPatterns != null) {
+    if (refPatterns != null && !refPatterns.isEmpty()) {
       this.refPatterns =
           refPatterns.stream().collect(collectingAndThen(toList(), Collections::unmodifiableList));
     } else {
@@ -210,6 +215,10 @@
     return values;
   }
 
+  public void setValues(List<LabelValue> values) {
+    this.values = sortValues(values);
+  }
+
   public LabelValue getMin() {
     if (values.isEmpty()) {
       return null;
diff --git a/java/com/google/gerrit/common/data/PatchScript.java b/java/com/google/gerrit/common/data/PatchScript.java
index c177e35..73e301b 100644
--- a/java/com/google/gerrit/common/data/PatchScript.java
+++ b/java/com/google/gerrit/common/data/PatchScript.java
@@ -37,30 +37,44 @@
     GITLINK
   }
 
+  public static class PatchScriptFileInfo {
+    public final String name;
+    public final FileMode mode;
+    public final SparseFileContent content;
+    public final DisplayMethod displayMethod;
+    public final String mimeType;
+    public final String commitId;
+
+    public PatchScriptFileInfo(
+        String name,
+        FileMode mode,
+        SparseFileContent content,
+        DisplayMethod displayMethod,
+        String mimeType,
+        String commitId) {
+      this.name = name;
+      this.mode = mode;
+      this.content = content;
+      this.displayMethod = displayMethod;
+      this.mimeType = mimeType;
+      this.commitId = commitId;
+    }
+  }
+
   private Change.Key changeId;
   private ChangeType changeType;
-  private String oldName;
-  private String newName;
-  private FileMode oldMode;
-  private FileMode newMode;
   private List<String> header;
   private DiffPreferencesInfo diffPrefs;
-  private SparseFileContent a;
-  private SparseFileContent b;
   private List<Edit> edits;
   private Set<Edit> editsDueToRebase;
-  private DisplayMethod displayMethodA;
-  private DisplayMethod displayMethodB;
-  private transient String mimeTypeA;
-  private transient String mimeTypeB;
   private CommentDetail comments;
   private List<Patch> history;
   private boolean hugeFile;
   private boolean intralineFailure;
   private boolean intralineTimeout;
   private boolean binary;
-  private transient String commitIdA;
-  private transient String commitIdB;
+  private PatchScriptFileInfo fileInfoA;
+  private PatchScriptFileInfo fileInfoB;
 
   public PatchScript(
       Change.Key ck,
@@ -89,50 +103,39 @@
       String cmb) {
     changeId = ck;
     changeType = ct;
-    oldName = on;
-    newName = nn;
-    oldMode = om;
-    newMode = nm;
     header = h;
     diffPrefs = dp;
-    a = ca;
-    b = cb;
     edits = e;
     this.editsDueToRebase = editsDueToRebase;
-    displayMethodA = ma;
-    displayMethodB = mb;
-    mimeTypeA = mta;
-    mimeTypeB = mtb;
     comments = cd;
     history = hist;
     hugeFile = hf;
     intralineFailure = idf;
     intralineTimeout = idt;
     binary = bin;
-    commitIdA = cma;
-    commitIdB = cmb;
-  }
 
-  protected PatchScript() {}
+    fileInfoA = new PatchScriptFileInfo(on, om, ca, ma, mta, cma);
+    fileInfoB = new PatchScriptFileInfo(nn, nm, cb, mb, mtb, cmb);
+  }
 
   public Change.Key getChangeId() {
     return changeId;
   }
 
   public DisplayMethod getDisplayMethodA() {
-    return displayMethodA;
+    return fileInfoA.displayMethod;
   }
 
   public DisplayMethod getDisplayMethodB() {
-    return displayMethodB;
+    return fileInfoB.displayMethod;
   }
 
   public FileMode getFileModeA() {
-    return oldMode;
+    return fileInfoA.mode;
   }
 
   public FileMode getFileModeB() {
-    return newMode;
+    return fileInfoB.mode;
   }
 
   public List<String> getPatchHeader() {
@@ -144,11 +147,11 @@
   }
 
   public String getOldName() {
-    return oldName;
+    return fileInfoA.name;
   }
 
   public String getNewName() {
-    return newName;
+    return fileInfoB.name;
   }
 
   public CommentDetail getCommentDetail() {
@@ -188,19 +191,19 @@
   }
 
   public SparseFileContent getA() {
-    return a;
+    return fileInfoA.content;
   }
 
   public SparseFileContent getB() {
-    return b;
+    return fileInfoB.content;
   }
 
   public String getMimeTypeA() {
-    return mimeTypeA;
+    return fileInfoA.mimeType;
   }
 
   public String getMimeTypeB() {
-    return mimeTypeB;
+    return fileInfoB.mimeType;
   }
 
   public List<Edit> getEdits() {
@@ -216,10 +219,18 @@
   }
 
   public String getCommitIdA() {
-    return commitIdA;
+    return fileInfoA.commitId;
   }
 
   public String getCommitIdB() {
-    return commitIdB;
+    return fileInfoB.commitId;
+  }
+
+  public PatchScriptFileInfo getFileInfoA() {
+    return fileInfoA;
+  }
+
+  public PatchScriptFileInfo getFileInfoB() {
+    return fileInfoB;
   }
 }
diff --git a/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java b/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
index 864839a..5f412ce 100644
--- a/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
+++ b/java/com/google/gerrit/elasticsearch/AbstractElasticIndex.java
@@ -26,6 +26,7 @@
 import com.google.common.collect.Lists;
 import com.google.common.collect.Streams;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.common.io.CharStreams;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.elasticsearch.ElasticMapping.MappingProperties;
@@ -68,7 +69,6 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.function.Function;
-import org.apache.commons.codec.binary.Base64;
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpStatus;
 import org.apache.http.StatusLine;
@@ -88,7 +88,7 @@
   protected static final String SETTINGS = "settings";
 
   protected static byte[] decodeBase64(String base64String) {
-    return Base64.decodeBase64(base64String);
+    return BaseEncoding.base64().decode(base64String);
   }
 
   protected static <T> List<T> decodeProtos(
@@ -268,7 +268,7 @@
         } else if (type == FieldType.TIMESTAMP) {
           rawFields.put(element.getKey(), new Timestamp(inner.getAsLong()));
         } else if (type == FieldType.STORED_ONLY) {
-          rawFields.put(element.getKey(), Base64.decodeBase64(inner.getAsString()));
+          rawFields.put(element.getKey(), decodeBase64(inner.getAsString()));
         } else {
           throw FieldType.badFieldType(type);
         }
diff --git a/java/com/google/gerrit/elasticsearch/BUILD b/java/com/google/gerrit/elasticsearch/BUILD
index edbd82c..8bab80b 100644
--- a/java/com/google/gerrit/elasticsearch/BUILD
+++ b/java/com/google/gerrit/elasticsearch/BUILD
@@ -19,7 +19,6 @@
         "//lib:guava",
         "//lib:jgit",
         "//lib:protobuf",
-        "//lib/commons:codec",
         "//lib/commons:lang",
         "//lib/elasticsearch-rest-client",
         "//lib/flogger:api",
diff --git a/java/com/google/gerrit/elasticsearch/ElasticAccountIndex.java b/java/com/google/gerrit/elasticsearch/ElasticAccountIndex.java
index a06f90f..c3e3264 100644
--- a/java/com/google/gerrit/elasticsearch/ElasticAccountIndex.java
+++ b/java/com/google/gerrit/elasticsearch/ElasticAccountIndex.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.elasticsearch;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.elasticsearch.ElasticMapping.MappingProperties;
 import com.google.gerrit.elasticsearch.bulk.BulkRequest;
 import com.google.gerrit.elasticsearch.bulk.IndexRequest;
@@ -74,7 +75,7 @@
   public void replace(AccountState as) {
     BulkRequest bulk =
         new IndexRequest(getId(as), indexName, type, client.adapter())
-            .add(new UpdateRequest<>(schema, as));
+            .add(new UpdateRequest<>(schema, as, ImmutableSet.of()));
 
     String uri = getURI(type, BULK);
     Response response = postRequest(uri, bulk, getRefreshParam());
diff --git a/java/com/google/gerrit/elasticsearch/ElasticChangeIndex.java b/java/com/google/gerrit/elasticsearch/ElasticChangeIndex.java
index 37184cc..084c2ec 100644
--- a/java/com/google/gerrit/elasticsearch/ElasticChangeIndex.java
+++ b/java/com/google/gerrit/elasticsearch/ElasticChangeIndex.java
@@ -22,6 +22,7 @@
 import com.google.common.collect.FluentIterable;
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Lists;
@@ -48,6 +49,7 @@
 import com.google.gerrit.server.ReviewerByEmailSet;
 import com.google.gerrit.server.ReviewerSet;
 import com.google.gerrit.server.StarredChangesUtil;
+import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.config.SitePaths;
 import com.google.gerrit.server.index.IndexUtils;
 import com.google.gerrit.server.index.change.ChangeField;
@@ -65,6 +67,7 @@
 import java.util.Optional;
 import java.util.Set;
 import org.apache.http.HttpStatus;
+import org.eclipse.jgit.lib.Config;
 import org.elasticsearch.client.Response;
 
 /** Secondary index implementation using Elasticsearch. */
@@ -91,6 +94,7 @@
   private final ChangeData.Factory changeDataFactory;
   private final Schema<ChangeData> schema;
   private final FieldDef<ChangeData, ?> idField;
+  private final ImmutableSet<String> skipFields;
 
   @Inject
   ElasticChangeIndex(
@@ -98,6 +102,7 @@
       ChangeData.Factory changeDataFactory,
       SitePaths sitePaths,
       ElasticRestClientProvider clientBuilder,
+      @GerritServerConfig Config gerritConfig,
       @Assisted Schema<ChangeData> schema) {
     super(cfg, sitePaths, schema, clientBuilder, CHANGES);
     this.changeDataFactory = changeDataFactory;
@@ -105,6 +110,10 @@
     this.mapping = new ChangeMapping(schema, client.adapter());
     this.idField =
         this.schema.useLegacyNumericFields() ? ChangeField.LEGACY_ID : ChangeField.LEGACY_ID_STR;
+    this.skipFields =
+        gerritConfig.getBoolean("index", "change", "indexMergeable", true)
+            ? ImmutableSet.of()
+            : ImmutableSet.of(ChangeField.MERGEABLE.getName());
   }
 
   @Override
@@ -123,7 +132,7 @@
     ElasticQueryAdapter adapter = client.adapter();
     BulkRequest bulk =
         new IndexRequest(getId(cd), indexName, adapter.getType(insertIndex), adapter)
-            .add(new UpdateRequest<>(schema, cd));
+            .add(new UpdateRequest<>(schema, cd, skipFields));
     if (adapter.deleteToReplace()) {
       bulk.add(new DeleteRequest(cd.getId().toString(), indexName, deleteIndex, adapter));
     }
@@ -263,7 +272,7 @@
 
     // Mergeable.
     JsonElement mergeableElement = source.get(ChangeField.MERGEABLE.getName());
-    if (mergeableElement != null) {
+    if (mergeableElement != null && !skipFields.contains(ChangeField.MERGEABLE.getName())) {
       String mergeable = mergeableElement.getAsString();
       if ("1".equals(mergeable)) {
         cd.setMergeable(true);
diff --git a/java/com/google/gerrit/elasticsearch/ElasticGroupIndex.java b/java/com/google/gerrit/elasticsearch/ElasticGroupIndex.java
index c215132..ce2025f 100644
--- a/java/com/google/gerrit/elasticsearch/ElasticGroupIndex.java
+++ b/java/com/google/gerrit/elasticsearch/ElasticGroupIndex.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.elasticsearch;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.elasticsearch.ElasticMapping.MappingProperties;
 import com.google.gerrit.elasticsearch.bulk.BulkRequest;
 import com.google.gerrit.elasticsearch.bulk.IndexRequest;
@@ -74,7 +75,7 @@
   public void replace(InternalGroup group) {
     BulkRequest bulk =
         new IndexRequest(getId(group), indexName, type, client.adapter())
-            .add(new UpdateRequest<>(schema, group));
+            .add(new UpdateRequest<>(schema, group, ImmutableSet.of()));
 
     String uri = getURI(type, BULK);
     Response response = postRequest(uri, bulk, getRefreshParam());
diff --git a/java/com/google/gerrit/elasticsearch/ElasticProjectIndex.java b/java/com/google/gerrit/elasticsearch/ElasticProjectIndex.java
index 29f8507..b636706 100644
--- a/java/com/google/gerrit/elasticsearch/ElasticProjectIndex.java
+++ b/java/com/google/gerrit/elasticsearch/ElasticProjectIndex.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.elasticsearch;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.elasticsearch.ElasticMapping.MappingProperties;
 import com.google.gerrit.elasticsearch.bulk.BulkRequest;
 import com.google.gerrit.elasticsearch.bulk.IndexRequest;
@@ -74,7 +75,7 @@
   public void replace(ProjectData projectState) {
     BulkRequest bulk =
         new IndexRequest(projectState.getProject().getName(), indexName, type, client.adapter())
-            .add(new UpdateRequest<>(schema, projectState));
+            .add(new UpdateRequest<>(schema, projectState, ImmutableSet.of()));
 
     String uri = getURI(type, BULK);
     Response response = postRequest(uri, bulk, getRefreshParam());
diff --git a/java/com/google/gerrit/elasticsearch/bulk/UpdateRequest.java b/java/com/google/gerrit/elasticsearch/bulk/UpdateRequest.java
index 2f0bd01..196b8d6 100644
--- a/java/com/google/gerrit/elasticsearch/bulk/UpdateRequest.java
+++ b/java/com/google/gerrit/elasticsearch/bulk/UpdateRequest.java
@@ -16,6 +16,7 @@
 
 import static java.util.stream.Collectors.toList;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Streams;
 import com.google.gerrit.elasticsearch.builders.XContentBuilder;
@@ -27,17 +28,19 @@
 
   private final Schema<V> schema;
   private final V v;
+  private final ImmutableSet<String> skipFields;
 
-  public UpdateRequest(Schema<V> schema, V v) {
+  public UpdateRequest(Schema<V> schema, V v, ImmutableSet<String> skipFields) {
     this.schema = schema;
     this.v = v;
+    this.skipFields = skipFields;
   }
 
   @Override
   protected String getRequest() {
     try (XContentBuilder closeable = new XContentBuilder()) {
       XContentBuilder builder = closeable.startObject();
-      for (Values<V> values : schema.buildFields(v)) {
+      for (Values<V> values : schema.buildFields(v, skipFields)) {
         String name = values.getField().getName();
         if (values.getField().isRepeatable()) {
           builder.field(name, Streams.stream(values.getValues()).collect(toList()));
diff --git a/java/com/google/gerrit/extensions/api/changes/ChangeApi.java b/java/com/google/gerrit/extensions/api/changes/ChangeApi.java
index 26a1a27..119d941 100644
--- a/java/com/google/gerrit/extensions/api/changes/ChangeApi.java
+++ b/java/com/google/gerrit/extensions/api/changes/ChangeApi.java
@@ -27,6 +27,7 @@
 import com.google.gerrit.extensions.common.EditInfo;
 import com.google.gerrit.extensions.common.MergePatchSetInput;
 import com.google.gerrit.extensions.common.PureRevertInfo;
+import com.google.gerrit.extensions.common.RevertSubmissionInfo;
 import com.google.gerrit.extensions.common.RobotCommentInfo;
 import com.google.gerrit.extensions.common.SuggestedReviewerInfo;
 import com.google.gerrit.extensions.restapi.NotImplementedException;
@@ -161,6 +162,12 @@
    */
   ChangeApi revert(RevertInput in) throws RestApiException;
 
+  default RevertSubmissionInfo revertSubmission() throws RestApiException {
+    return revertSubmission(new RevertInput());
+  }
+
+  RevertSubmissionInfo revertSubmission(RevertInput in) throws RestApiException;
+
   /** Create a merge patch set for the change. */
   ChangeInfo createMergePatchSet(MergePatchSetInput in) throws RestApiException;
 
@@ -502,6 +509,11 @@
     }
 
     @Override
+    public RevertSubmissionInfo revertSubmission(RevertInput in) throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
     public void rebase(RebaseInput in) throws RestApiException {
       throw new NotImplementedException();
     }
diff --git a/java/com/google/gerrit/extensions/api/projects/CommentLinkInput.java b/java/com/google/gerrit/extensions/api/projects/CommentLinkInput.java
new file mode 100644
index 0000000..3aad7e1
--- /dev/null
+++ b/java/com/google/gerrit/extensions/api/projects/CommentLinkInput.java
@@ -0,0 +1,27 @@
+// Copyright (C) 2018 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.api.projects;
+
+/*
+ * Input for a commentlink configuration on a project.
+ */
+public class CommentLinkInput {
+  /** A JavaScript regular expression to match positions to be replaced with a hyperlink. */
+  public String match;
+  /** The URL to direct the user to whenever the regular expression is matched. */
+  public String link;
+  /** Whether the commentlink is enabled. */
+  public Boolean enabled;
+}
diff --git a/java/com/google/gerrit/extensions/api/projects/ConfigInput.java b/java/com/google/gerrit/extensions/api/projects/ConfigInput.java
index 1a6d77b..8005fc5 100644
--- a/java/com/google/gerrit/extensions/api/projects/ConfigInput.java
+++ b/java/com/google/gerrit/extensions/api/projects/ConfigInput.java
@@ -38,4 +38,5 @@
   public SubmitType submitType;
   public ProjectState state;
   public Map<String, Map<String, ConfigValue>> pluginConfigValues;
+  public Map<String, CommentLinkInput> commentLinks;
 }
diff --git a/java/com/google/gerrit/extensions/api/projects/LabelApi.java b/java/com/google/gerrit/extensions/api/projects/LabelApi.java
new file mode 100644
index 0000000..975a57e
--- /dev/null
+++ b/java/com/google/gerrit/extensions/api/projects/LabelApi.java
@@ -0,0 +1,61 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.api.projects;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.NotImplementedException;
+import com.google.gerrit.extensions.restapi.RestApiException;
+
+public interface LabelApi {
+  LabelApi create(LabelDefinitionInput input) throws RestApiException;
+
+  LabelDefinitionInfo get() throws RestApiException;
+
+  LabelDefinitionInfo update(LabelDefinitionInput input) throws RestApiException;
+
+  default void delete() throws RestApiException {
+    delete(null);
+  }
+
+  void delete(@Nullable String commitMessage) throws RestApiException;
+
+  /**
+   * A default implementation which allows source compatibility when adding new methods to the
+   * interface.
+   */
+  class NotImplemented implements LabelApi {
+    @Override
+    public LabelApi create(LabelDefinitionInput input) throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
+    public LabelDefinitionInfo get() throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
+    public LabelDefinitionInfo update(LabelDefinitionInput input) throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
+    public void delete(@Nullable String commitMessage) throws RestApiException {
+      throw new NotImplementedException();
+    }
+  }
+}
diff --git a/java/com/google/gerrit/extensions/api/projects/ParentInput.java b/java/com/google/gerrit/extensions/api/projects/ParentInput.java
index 6e481ae..d68bb3b 100644
--- a/java/com/google/gerrit/extensions/api/projects/ParentInput.java
+++ b/java/com/google/gerrit/extensions/api/projects/ParentInput.java
@@ -14,9 +14,9 @@
 
 package com.google.gerrit.extensions.api.projects;
 
+import com.google.gerrit.extensions.common.InputWithCommitMessage;
 import com.google.gerrit.extensions.restapi.DefaultInput;
 
-public class ParentInput {
+public class ParentInput extends InputWithCommitMessage {
   @DefaultInput public String parent;
-  public String commitMessage;
 }
diff --git a/java/com/google/gerrit/extensions/api/projects/ProjectApi.java b/java/com/google/gerrit/extensions/api/projects/ProjectApi.java
index c6d9dee..9873995 100644
--- a/java/com/google/gerrit/extensions/api/projects/ProjectApi.java
+++ b/java/com/google/gerrit/extensions/api/projects/ProjectApi.java
@@ -18,7 +18,9 @@
 import com.google.gerrit.extensions.api.access.ProjectAccessInput;
 import com.google.gerrit.extensions.api.config.AccessCheckInfo;
 import com.google.gerrit.extensions.api.config.AccessCheckInput;
+import com.google.gerrit.extensions.common.BatchLabelInput;
 import com.google.gerrit.extensions.common.ChangeInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
 import com.google.gerrit.extensions.common.ProjectInfo;
 import com.google.gerrit.extensions.restapi.NotImplementedException;
 import com.google.gerrit.extensions.restapi.RestApiException;
@@ -204,6 +206,28 @@
   /** Reindexes all changes of the project. */
   void indexChanges() throws RestApiException;
 
+  ListLabelsRequest labels() throws RestApiException;
+
+  abstract class ListLabelsRequest {
+    protected boolean inherited;
+
+    public abstract List<LabelDefinitionInfo> get() throws RestApiException;
+
+    public ListLabelsRequest withInherited(boolean inherited) {
+      this.inherited = inherited;
+      return this;
+    }
+  }
+
+  LabelApi label(String labelName) throws RestApiException;
+
+  /**
+   * Adds, updates and deletes label definitions in a batch.
+   *
+   * @param input input that describes additions, updates and deletions of label definitions
+   */
+  void labels(BatchLabelInput input) throws RestApiException;
+
   /**
    * A default implementation which allows source compatibility when adding new methods to the
    * interface.
@@ -378,5 +402,20 @@
     public void indexChanges() throws RestApiException {
       throw new NotImplementedException();
     }
+
+    @Override
+    public ListLabelsRequest labels() throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
+    public LabelApi label(String labelName) throws RestApiException {
+      throw new NotImplementedException();
+    }
+
+    @Override
+    public void labels(BatchLabelInput input) throws RestApiException {
+      throw new NotImplementedException();
+    }
   }
 }
diff --git a/java/com/google/gerrit/extensions/api/projects/SetDashboardInput.java b/java/com/google/gerrit/extensions/api/projects/SetDashboardInput.java
index 0083c0e..3662b7f 100644
--- a/java/com/google/gerrit/extensions/api/projects/SetDashboardInput.java
+++ b/java/com/google/gerrit/extensions/api/projects/SetDashboardInput.java
@@ -14,9 +14,9 @@
 
 package com.google.gerrit.extensions.api.projects;
 
+import com.google.gerrit.extensions.common.InputWithCommitMessage;
 import com.google.gerrit.extensions.restapi.DefaultInput;
 
-public class SetDashboardInput {
+public class SetDashboardInput extends InputWithCommitMessage {
   @DefaultInput public String id;
-  public String commitMessage;
 }
diff --git a/java/com/google/gerrit/extensions/common/BatchLabelInput.java b/java/com/google/gerrit/extensions/common/BatchLabelInput.java
new file mode 100644
index 0000000..eb4c581
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/BatchLabelInput.java
@@ -0,0 +1,26 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import java.util.List;
+import java.util.Map;
+
+/** Input for the REST API that describes additions, updates and deletions of label definitions. */
+public class BatchLabelInput {
+  public String commitMessage;
+  public List<String> delete;
+  public List<LabelDefinitionInput> create;
+  public Map<String, LabelDefinitionInput> update;
+}
diff --git a/java/com/google/gerrit/extensions/common/ChangeInfo.java b/java/com/google/gerrit/extensions/common/ChangeInfo.java
index 9a739ef..0d7c5c7 100644
--- a/java/com/google/gerrit/extensions/common/ChangeInfo.java
+++ b/java/com/google/gerrit/extensions/common/ChangeInfo.java
@@ -52,6 +52,7 @@
   public Boolean workInProgress;
   public Boolean hasReviewStarted;
   public Integer revertOf;
+  public String submissionId;
 
   public int _number;
 
diff --git a/java/com/google/gerrit/extensions/common/InputWithCommitMessage.java b/java/com/google/gerrit/extensions/common/InputWithCommitMessage.java
new file mode 100644
index 0000000..34bc203
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/InputWithCommitMessage.java
@@ -0,0 +1,30 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import com.google.gerrit.common.Nullable;
+
+/** A generic input with a commit message only. */
+public class InputWithCommitMessage {
+  @Nullable public String commitMessage;
+
+  public InputWithCommitMessage() {
+    this(null);
+  }
+
+  public InputWithCommitMessage(@Nullable String commitMessage) {
+    this.commitMessage = commitMessage;
+  }
+}
diff --git a/java/com/google/gerrit/extensions/common/InputWithMessage.java b/java/com/google/gerrit/extensions/common/InputWithMessage.java
new file mode 100644
index 0000000..45d23cf
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/InputWithMessage.java
@@ -0,0 +1,34 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import com.google.gerrit.common.Nullable;
+
+/**
+ * A generic input with a message only.
+ *
+ * <p>See also {@link InputWithCommitMessage}.
+ */
+public class InputWithMessage {
+  @Nullable public String message;
+
+  public InputWithMessage() {
+    this(null);
+  }
+
+  public InputWithMessage(@Nullable String message) {
+    this.message = message;
+  }
+}
diff --git a/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java b/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java
new file mode 100644
index 0000000..64c3997
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/LabelDefinitionInfo.java
@@ -0,0 +1,37 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import java.util.List;
+import java.util.Map;
+
+public class LabelDefinitionInfo {
+  public String name;
+  public String projectName;
+  public String function;
+  public Map<String, String> values;
+  public short defaultValue;
+  public List<String> branches;
+  public Boolean canOverride;
+  public Boolean copyAnyScore;
+  public Boolean copyMinScore;
+  public Boolean copyMaxScore;
+  public Boolean copyAllScoresIfNoChange;
+  public Boolean copyAllScoresIfNoCodeChange;
+  public Boolean copyAllScoresOnTrivialRebase;
+  public Boolean copyAllScoresOnMergeFirstParentUpdate;
+  public Boolean allowPostSubmit;
+  public Boolean ignoreSelfApproval;
+}
diff --git a/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java b/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java
new file mode 100644
index 0000000..0523f61
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/LabelDefinitionInput.java
@@ -0,0 +1,36 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import java.util.List;
+import java.util.Map;
+
+public class LabelDefinitionInput extends InputWithCommitMessage {
+  public String name;
+  public String function;
+  public Map<String, String> values;
+  public Short defaultValue;
+  public List<String> branches;
+  public Boolean canOverride;
+  public Boolean copyAnyScore;
+  public Boolean copyMinScore;
+  public Boolean copyMaxScore;
+  public Boolean copyAllScoresIfNoChange;
+  public Boolean copyAllScoresIfNoCodeChange;
+  public Boolean copyAllScoresOnTrivialRebase;
+  public Boolean copyAllScoresOnMergeFirstParentUpdate;
+  public Boolean allowPostSubmit;
+  public Boolean ignoreSelfApproval;
+}
diff --git a/java/com/google/gerrit/extensions/common/RevertSubmissionInfo.java b/java/com/google/gerrit/extensions/common/RevertSubmissionInfo.java
new file mode 100644
index 0000000..dabd035
--- /dev/null
+++ b/java/com/google/gerrit/extensions/common/RevertSubmissionInfo.java
@@ -0,0 +1,21 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.extensions.common;
+
+import java.util.List;
+
+public class RevertSubmissionInfo {
+  public List<ChangeInfo> revertChanges;
+}
diff --git a/java/com/google/gerrit/extensions/restapi/Response.java b/java/com/google/gerrit/extensions/restapi/Response.java
index 5504cfd..bf363d8 100644
--- a/java/com/google/gerrit/extensions/restapi/Response.java
+++ b/java/com/google/gerrit/extensions/restapi/Response.java
@@ -14,10 +14,6 @@
 
 package com.google.gerrit.extensions.restapi;
 
-import static com.google.common.base.Preconditions.checkArgument;
-
-import com.google.gerrit.common.Nullable;
-import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
 /** Special return value to mean specific HTTP status codes in a REST API. */
@@ -30,6 +26,12 @@
     return new Impl<>(200, value);
   }
 
+  /** HTTP 200 OK: with empty value. */
+  public static Response<String> ok() {
+    return ok("");
+  }
+
+  /** HTTP 200 OK: with forced revalidation of cache. */
   public static <T> Response<T> withMustRevalidate(T value) {
     return ok(value).caching(CacheControl.PRIVATE(0, TimeUnit.SECONDS).setMustRevalidate());
   }
@@ -39,6 +41,11 @@
     return new Impl<>(201, value);
   }
 
+  /** HTTP 201 Created: with empty value. */
+  public static Response<String> created() {
+    return created("");
+  }
+
   /** HTTP 202 Accepted: accepted as background task. */
   public static Accepted accepted(String location) {
     return new Accepted(location);
@@ -55,48 +62,24 @@
     return new Redirect(location);
   }
 
-  /**
-   * HTTP 500 Internal Server Error: failure due to an unexpected exception.
-   *
-   * <p>Can be returned from REST endpoints, instead of throwing the exception, if additional
-   * properties (e.g. a traceId) should be set on the response.
-   *
-   * @param cause the exception that caused the request to fail, must not be a {@link
-   *     RestApiException} because such an exception would result in a 4XX response code
-   */
-  public static <T> InternalServerError<T> internalServerError(Exception cause) {
-    return new InternalServerError<>(cause);
-  }
-
   /** Arbitrary status code with wrapped result. */
   public static <T> Response<T> withStatusCode(int statusCode, T value) {
     return new Impl<>(statusCode, value);
   }
 
   @SuppressWarnings({"unchecked", "rawtypes"})
-  public static <T> T unwrap(T obj) throws Exception {
+  public static <T> T unwrap(T obj) {
     while (obj instanceof Response) {
       obj = (T) ((Response) obj).value();
     }
     return obj;
   }
 
-  private String traceId;
-
-  public Response<T> traceId(@Nullable String traceId) {
-    this.traceId = traceId;
-    return this;
-  }
-
-  public Optional<String> traceId() {
-    return Optional.ofNullable(traceId);
-  }
-
   public abstract boolean isNone();
 
   public abstract int statusCode();
 
-  public abstract T value() throws Exception;
+  public abstract T value();
 
   public abstract CacheControl caching();
 
@@ -286,57 +269,4 @@
       return String.format("[202 Accepted] %s", location);
     }
   }
-
-  public static final class InternalServerError<T> extends Response<T> {
-    private final Exception cause;
-
-    private InternalServerError(Exception cause) {
-      checkArgument(!(cause instanceof RestApiException), "cause must not be a RestApiException");
-      this.cause = cause;
-    }
-
-    @Override
-    public boolean isNone() {
-      return false;
-    }
-
-    @Override
-    public int statusCode() {
-      return 500;
-    }
-
-    @Override
-    public T value() throws Exception {
-      throw cause();
-    }
-
-    @Override
-    public CacheControl caching() {
-      return CacheControl.NONE;
-    }
-
-    @Override
-    public Response<T> caching(CacheControl c) {
-      throw new UnsupportedOperationException();
-    }
-
-    public Exception cause() {
-      return cause;
-    }
-
-    @Override
-    public int hashCode() {
-      return cause.hashCode();
-    }
-
-    @Override
-    public boolean equals(Object o) {
-      return o instanceof InternalServerError && ((InternalServerError<?>) o).cause.equals(cause);
-    }
-
-    @Override
-    public String toString() {
-      return String.format("[500 Internal Server Error] %s", cause.getClass());
-    }
-  }
 }
diff --git a/java/com/google/gerrit/gpg/PublicKeyStore.java b/java/com/google/gerrit/gpg/PublicKeyStore.java
index 519c400..2cce480 100644
--- a/java/com/google/gerrit/gpg/PublicKeyStore.java
+++ b/java/com/google/gerrit/gpg/PublicKeyStore.java
@@ -21,6 +21,7 @@
 
 import com.google.common.base.Preconditions;
 import com.google.common.io.ByteStreams;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.git.ObjectIds;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -387,9 +388,10 @@
         toAdd.clear();
         toRemove.clear();
         break;
+      case LOCK_FAILURE:
+        throw new LockFailureException("Failed to store public keys", ru);
       case FORCED:
       case IO_FAILURE:
-      case LOCK_FAILURE:
       case NOT_ATTEMPTED:
       case REJECTED:
       case REJECTED_CURRENT_BRANCH:
diff --git a/java/com/google/gerrit/httpd/BUILD b/java/com/google/gerrit/httpd/BUILD
index bcb2a2a..d6a43b91 100644
--- a/java/com/google/gerrit/httpd/BUILD
+++ b/java/com/google/gerrit/httpd/BUILD
@@ -38,7 +38,6 @@
         "//lib:soy",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:codec",
         "//lib/commons:lang",
         "//lib/flogger:api",
         "//lib/guice",
diff --git a/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java b/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
index 88a3f0a..d43fcc7 100644
--- a/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
+++ b/java/com/google/gerrit/httpd/ProjectBasicAuthFilter.java
@@ -20,6 +20,7 @@
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.extensions.client.GitBasicAuthPolicy;
 import com.google.gerrit.extensions.registration.DynamicItem;
@@ -48,7 +49,6 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpServletResponseWrapper;
-import org.apache.commons.codec.binary.Base64;
 
 /**
  * Authenticates the current user by HTTP basic authentication.
@@ -110,7 +110,7 @@
       return true;
     }
 
-    final byte[] decoded = Base64.decodeBase64(hdr.substring(LIT_BASIC.length()));
+    final byte[] decoded = BaseEncoding.base64().decode(hdr.substring(LIT_BASIC.length()));
     String usernamePassword = new String(decoded, encoding(req));
     int splitPos = usernamePassword.indexOf(':');
     if (splitPos < 1) {
diff --git a/java/com/google/gerrit/httpd/ProjectOAuthFilter.java b/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
index 4b5742d..693232f 100644
--- a/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
+++ b/java/com/google/gerrit/httpd/ProjectOAuthFilter.java
@@ -22,6 +22,7 @@
 import com.google.common.base.Strings;
 import com.google.common.collect.Iterables;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.extensions.auth.oauth.OAuthLoginProvider;
 import com.google.gerrit.extensions.registration.DynamicItem;
@@ -53,7 +54,6 @@
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import javax.servlet.http.HttpServletResponseWrapper;
-import org.apache.commons.codec.binary.Base64;
 import org.eclipse.jgit.lib.Config;
 
 /**
@@ -225,7 +225,7 @@
 
   private AuthInfo extractAuthInfo(String hdr, String encoding)
       throws UnsupportedEncodingException {
-    byte[] decoded = Base64.decodeBase64(hdr.substring(BASIC.length()));
+    byte[] decoded = BaseEncoding.base64().decode(hdr.substring(BASIC.length()));
     String usernamePassword = new String(decoded, encoding);
     int splitPos = usernamePassword.indexOf(':');
     if (splitPos < 1 || splitPos == usernamePassword.length() - 1) {
diff --git a/java/com/google/gerrit/httpd/RemoteUserUtil.java b/java/com/google/gerrit/httpd/RemoteUserUtil.java
index a02b5a0..84954dc 100644
--- a/java/com/google/gerrit/httpd/RemoteUserUtil.java
+++ b/java/com/google/gerrit/httpd/RemoteUserUtil.java
@@ -18,8 +18,8 @@
 import static com.google.common.net.HttpHeaders.AUTHORIZATION;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.io.BaseEncoding;
 import javax.servlet.http.HttpServletRequest;
-import org.eclipse.jgit.util.Base64;
 
 public class RemoteUserUtil {
   /**
@@ -70,7 +70,7 @@
 
     } else if (auth.startsWith("Basic ")) {
       auth = auth.substring("Basic ".length());
-      auth = new String(Base64.decode(auth), UTF_8);
+      auth = new String(BaseEncoding.base64().decode(auth), UTF_8);
       final int c = auth.indexOf(':');
       return c > 0 ? auth.substring(0, c) : null;
 
diff --git a/java/com/google/gerrit/httpd/auth/oauth/BUILD b/java/com/google/gerrit/httpd/auth/oauth/BUILD
index dd4549e..11c9295 100644
--- a/java/com/google/gerrit/httpd/auth/oauth/BUILD
+++ b/java/com/google/gerrit/httpd/auth/oauth/BUILD
@@ -16,7 +16,6 @@
         "//lib:guava",
         "//lib:jgit",
         "//lib:servlet-api",
-        "//lib/commons:codec",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/guice:guice-servlet",
diff --git a/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java b/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
index 84dee6e..c7b65d0 100644
--- a/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
+++ b/java/com/google/gerrit/httpd/auth/oauth/OAuthSession.java
@@ -19,6 +19,7 @@
 import com.google.common.base.CharMatcher;
 import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.extensions.auth.oauth.OAuthServiceProvider;
 import com.google.gerrit.extensions.auth.oauth.OAuthToken;
@@ -45,7 +46,6 @@
 import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.apache.commons.codec.binary.Base64;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @SessionScoped
@@ -244,7 +244,7 @@
   private static String generateRandomState() {
     byte[] state = new byte[32];
     randomState.nextBytes(state);
-    return Base64.encodeBase64URLSafeString(state);
+    return BaseEncoding.base64Url().encode(state);
   }
 
   @Override
diff --git a/java/com/google/gerrit/httpd/auth/openid/BUILD b/java/com/google/gerrit/httpd/auth/openid/BUILD
index 94f436b..29841aa 100644
--- a/java/com/google/gerrit/httpd/auth/openid/BUILD
+++ b/java/com/google/gerrit/httpd/auth/openid/BUILD
@@ -17,7 +17,6 @@
         "//java/com/google/gerrit/server",
         "//lib:guava",
         "//lib:servlet-api",
-        "//lib/commons:codec",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/guice:guice-servlet",
diff --git a/java/com/google/gerrit/httpd/auth/openid/OAuthSessionOverOpenID.java b/java/com/google/gerrit/httpd/auth/openid/OAuthSessionOverOpenID.java
index bbdb0c4..f9e6286 100644
--- a/java/com/google/gerrit/httpd/auth/openid/OAuthSessionOverOpenID.java
+++ b/java/com/google/gerrit/httpd/auth/openid/OAuthSessionOverOpenID.java
@@ -18,6 +18,7 @@
 
 import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.extensions.auth.oauth.OAuthServiceProvider;
 import com.google.gerrit.extensions.auth.oauth.OAuthToken;
@@ -43,7 +44,6 @@
 import javax.servlet.ServletRequest;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.apache.commons.codec.binary.Base64;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 /** OAuth protocol implementation */
@@ -229,7 +229,7 @@
   private static String generateRandomState() {
     byte[] state = new byte[32];
     randomState.nextBytes(state);
-    return Base64.encodeBase64URLSafeString(state);
+    return BaseEncoding.base64Url().encode(state);
   }
 
   @Override
diff --git a/java/com/google/gerrit/httpd/init/WebAppInitializer.java b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
index 952c509..9b39a2d 100644
--- a/java/com/google/gerrit/httpd/init/WebAppInitializer.java
+++ b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
@@ -99,6 +99,7 @@
 import com.google.gerrit.sshd.SshModule;
 import com.google.gerrit.sshd.commands.DefaultCommandModule;
 import com.google.gerrit.sshd.commands.IndexCommandsModule;
+import com.google.gerrit.sshd.commands.SequenceCommandsModule;
 import com.google.gerrit.sshd.plugin.LfsPluginAuthCommand;
 import com.google.inject.AbstractModule;
 import com.google.inject.CreationException;
@@ -372,6 +373,7 @@
             sysInjector.getInstance(DownloadConfig.class),
             sysInjector.getInstance(LfsPluginAuthCommand.Module.class)));
     modules.add(new IndexCommandsModule(sysInjector));
+    modules.add(new SequenceCommandsModule());
     return sysInjector.createChildInjector(modules);
   }
 
diff --git a/java/com/google/gerrit/httpd/restapi/RestApiMetrics.java b/java/com/google/gerrit/httpd/restapi/RestApiMetrics.java
index fc099a6..aa1b921 100644
--- a/java/com/google/gerrit/httpd/restapi/RestApiMetrics.java
+++ b/java/com/google/gerrit/httpd/restapi/RestApiMetrics.java
@@ -15,10 +15,11 @@
 package com.google.gerrit.httpd.restapi;
 
 import com.google.common.base.Strings;
+import com.google.gerrit.common.Nullable;
 import com.google.gerrit.extensions.registration.PluginName;
 import com.google.gerrit.httpd.restapi.RestApiServlet.ViewData;
 import com.google.gerrit.metrics.Counter1;
-import com.google.gerrit.metrics.Counter2;
+import com.google.gerrit.metrics.Counter3;
 import com.google.gerrit.metrics.Description;
 import com.google.gerrit.metrics.Description.Units;
 import com.google.gerrit.metrics.Field;
@@ -36,7 +37,7 @@
   };
 
   final Counter1<String> count;
-  final Counter2<String, Integer> errorCount;
+  final Counter3<String, Integer, String> errorCount;
   final Timer1<String> serverLatency;
   final Histogram1<String> responseBytes;
 
@@ -59,6 +60,9 @@
             viewField,
             Field.ofInteger("error_code", Metadata.Builder::httpStatus)
                 .description("HTTP status code")
+                .build(),
+            Field.ofString("cause", Metadata.Builder::cause)
+                .description("The cause of the error.")
                 .build());
 
     serverLatency =
@@ -79,16 +83,19 @@
   }
 
   String view(ViewData viewData) {
-    String impl = viewData.view.getClass().getName().replace('$', '.');
+    return view(viewData.view.getClass(), viewData.pluginName);
+  }
+
+  String view(Class<?> clazz, @Nullable String pluginName) {
+    String impl = clazz.getName().replace('$', '.');
     for (String p : PKGS) {
       if (impl.startsWith(p)) {
         impl = impl.substring(p.length());
         break;
       }
     }
-    if (!Strings.isNullOrEmpty(viewData.pluginName)
-        && !PluginName.GERRIT.equals(viewData.pluginName)) {
-      impl = viewData.pluginName + '-' + impl;
+    if (!Strings.isNullOrEmpty(pluginName) && !PluginName.GERRIT.equals(pluginName)) {
+      impl = pluginName + '-' + impl;
     }
     return impl;
   }
diff --git a/java/com/google/gerrit/httpd/restapi/RestApiServlet.java b/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
index 61fa4f9..0535397 100644
--- a/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
+++ b/java/com/google/gerrit/httpd/restapi/RestApiServlet.java
@@ -17,6 +17,7 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkState;
+import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.flogger.LazyArgs.lazy;
 import static com.google.common.net.HttpHeaders.ACCESS_CONTROL_ALLOW_CREDENTIALS;
 import static com.google.common.net.HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS;
@@ -103,6 +104,7 @@
 import com.google.gerrit.server.AccessPath;
 import com.google.gerrit.server.AnonymousUser;
 import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.ExceptionHook;
 import com.google.gerrit.server.OptionUtil;
 import com.google.gerrit.server.RequestInfo;
 import com.google.gerrit.server.RequestListener;
@@ -123,6 +125,9 @@
 import com.google.gerrit.server.quota.QuotaException;
 import com.google.gerrit.server.restapi.change.ChangesCollection;
 import com.google.gerrit.server.restapi.project.ProjectsCollection;
+import com.google.gerrit.server.update.RetryHelper;
+import com.google.gerrit.server.update.RetryHelper.Action;
+import com.google.gerrit.server.update.RetryHelper.ActionType;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.gerrit.util.http.CacheHeaders;
@@ -170,6 +175,7 @@
 import java.util.Set;
 import java.util.TreeMap;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.regex.Pattern;
 import java.util.stream.Stream;
 import java.util.zip.GZIPOutputStream;
@@ -241,6 +247,8 @@
     final Config config;
     final DynamicSet<PerformanceLogger> performanceLoggers;
     final ChangeFinder changeFinder;
+    final RetryHelper retryHelper;
+    final PluginSetContext<ExceptionHook> exceptionHooks;
 
     @Inject
     Globals(
@@ -254,7 +262,9 @@
         RestApiQuotaEnforcer quotaChecker,
         @GerritServerConfig Config config,
         DynamicSet<PerformanceLogger> performanceLoggers,
-        ChangeFinder changeFinder) {
+        ChangeFinder changeFinder,
+        RetryHelper retryHelper,
+        PluginSetContext<ExceptionHook> exceptionHooks) {
       this.currentUser = currentUser;
       this.webSession = webSession;
       this.paramParser = paramParser;
@@ -266,6 +276,8 @@
       this.config = config;
       this.performanceLoggers = performanceLoggers;
       this.changeFinder = changeFinder;
+      this.retryHelper = retryHelper;
+      this.exceptionHooks = exceptionHooks;
       allowOrigin = makeAllowOrigin(config);
     }
 
@@ -280,7 +292,6 @@
 
   private final Globals globals;
   private final Provider<RestCollection<RestResource, RestResource>> members;
-  private Optional<String> traceId = Optional.empty();
 
   public RestApiServlet(
       Globals globals, RestCollection<? extends RestResource, ? extends RestResource> members) {
@@ -306,6 +317,7 @@
     res.setHeader("X-Content-Type-Options", "nosniff");
     int status = SC_OK;
     long responseBytes = -1;
+    Optional<Exception> cause = Optional.empty();
     Response<?> response = null;
     QueryParams qp = null;
     Object inputRequestBody = null;
@@ -326,12 +338,7 @@
         // TraceIT#performanceLoggingForRestCall()).
         try (PerformanceLogContext performanceLogContext =
             new PerformanceLogContext(globals.config, globals.performanceLoggers)) {
-          logger.atFinest().log(
-              "Received REST request: %s %s (parameters: %s)",
-              req.getMethod(), req.getRequestURI(), getParameterNames(req));
-          logger.atFinest().log("Calling user: %s", globals.currentUser.get().getLoggableName());
-          logger.atFinest().log(
-              "Groups: %s", globals.currentUser.get().getEffectiveGroups().getKnownGroups());
+          traceRequestData(req);
 
           if (isCorsPreflight(req)) {
             doCorsPreflight(req, res);
@@ -376,7 +383,7 @@
           } else {
             IdString id = path.remove(0);
             try {
-              rsrc = rc.parse(rsrc, id);
+              rsrc = parseResourceWithRetry(req, traceContext, viewData.pluginName, rc, rsrc, id);
               globals.quotaChecker.enforce(rsrc, req);
               if (path.isEmpty()) {
                 checkPreconditions(req);
@@ -449,7 +456,7 @@
             }
             IdString id = path.remove(0);
             try {
-              rsrc = c.parse(rsrc, id);
+              rsrc = parseResourceWithRetry(req, traceContext, viewData.pluginName, c, rsrc, id);
               checkPreconditions(req);
               viewData = new ViewData(null, null);
             } catch (ResourceNotFoundException e) {
@@ -495,7 +502,9 @@
           }
 
           if (viewData.view instanceof RestReadView<?> && isRead(req)) {
-            response = ((RestReadView<RestResource>) viewData.view).apply(rsrc);
+            response =
+                invokeRestReadViewWithRetry(
+                    req, traceContext, viewData, (RestReadView<RestResource>) viewData.view, rsrc);
           } else if (viewData.view instanceof RestModifyView<?, ?>) {
             @SuppressWarnings("unchecked")
             RestModifyView<RestResource, Object> m =
@@ -503,7 +512,10 @@
 
             Type type = inputType(m);
             inputRequestBody = parseRequest(req, type);
-            response = m.apply(rsrc, inputRequestBody);
+            response =
+                invokeRestModifyViewWithRetry(
+                    req, traceContext, viewData, m, rsrc, inputRequestBody);
+
             if (inputRequestBody instanceof RawInput) {
               try (InputStream is = req.getInputStream()) {
                 ServletUtils.consumeRequestBody(is);
@@ -516,7 +528,9 @@
 
             Type type = inputType(m);
             inputRequestBody = parseRequest(req, type);
-            response = m.apply(rsrc, path.get(0), inputRequestBody);
+            response =
+                invokeRestCollectionCreateViewWithRetry(
+                    req, traceContext, viewData, m, rsrc, path.get(0), inputRequestBody);
             if (inputRequestBody instanceof RawInput) {
               try (InputStream is = req.getInputStream()) {
                 ServletUtils.consumeRequestBody(is);
@@ -529,7 +543,9 @@
 
             Type type = inputType(m);
             inputRequestBody = parseRequest(req, type);
-            response = m.apply(rsrc, path.get(0), inputRequestBody);
+            response =
+                invokeRestCollectionDeleteMissingViewWithRetry(
+                    req, traceContext, viewData, m, rsrc, path.get(0), inputRequestBody);
             if (inputRequestBody instanceof RawInput) {
               try (InputStream is = req.getInputStream()) {
                 ServletUtils.consumeRequestBody(is);
@@ -542,7 +558,9 @@
 
             Type type = inputType(m);
             inputRequestBody = parseRequest(req, type);
-            response = m.apply(rsrc, inputRequestBody);
+            response =
+                invokeRestCollectionModifyViewWithRetry(
+                    req, traceContext, viewData, m, rsrc, inputRequestBody);
             if (inputRequestBody instanceof RawInput) {
               try (InputStream is = req.getInputStream()) {
                 ServletUtils.consumeRequestBody(is);
@@ -552,9 +570,6 @@
             throw new ResourceNotFoundException();
           }
 
-          traceId = response.traceId();
-          traceId.ifPresent(traceId -> res.addHeader(X_GERRIT_TRACE, traceId));
-
           if (response instanceof Response.Redirect) {
             CacheHeaders.setNotCacheable(res);
             String location = ((Response.Redirect) response).location();
@@ -567,12 +582,6 @@
             res.setHeader(HttpHeaders.LOCATION, ((Response.Accepted) response).location());
             logger.atFinest().log("REST call succeeded: %d", response.statusCode());
             return;
-          } else if (response instanceof Response.InternalServerError) {
-            // Rethrow the exception to have exactly the same error handling as if the REST endpoint
-            // would have thrown the exception directly, instead of returning
-            // Response.InternalServerError.
-            Exception cause = ((Response.InternalServerError<?>) response).cause();
-            throw cause;
           }
 
           status = response.statusCode();
@@ -590,22 +599,28 @@
           }
         }
       } catch (MalformedJsonException | JsonParseException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req, res, status = SC_BAD_REQUEST, "Invalid " + JSON_TYPE + " in request", e);
       } catch (BadRequestException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req, res, status = SC_BAD_REQUEST, messageOr(e, "Bad Request"), e.caching(), e);
       } catch (AuthException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(req, res, status = SC_FORBIDDEN, messageOr(e, "Forbidden"), e.caching(), e);
       } catch (AmbiguousViewException e) {
+        cause = Optional.of(e);
         responseBytes = replyError(req, res, status = SC_NOT_FOUND, messageOr(e, "Ambiguous"), e);
       } catch (ResourceNotFoundException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(req, res, status = SC_NOT_FOUND, messageOr(e, "Not Found"), e.caching(), e);
       } catch (MethodNotAllowedException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req,
@@ -615,9 +630,11 @@
                 e.caching(),
                 e);
       } catch (ResourceConflictException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(req, res, status = SC_CONFLICT, messageOr(e, "Conflict"), e.caching(), e);
       } catch (PreconditionFailedException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req,
@@ -627,6 +644,7 @@
                 e.caching(),
                 e);
       } catch (UnprocessableEntityException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req,
@@ -636,19 +654,22 @@
                 e.caching(),
                 e);
       } catch (NotImplementedException e) {
+        cause = Optional.of(e);
         logger.atSevere().withCause(e).log("Error in %s %s", req.getMethod(), uriForLogging(req));
         responseBytes =
             replyError(req, res, status = SC_NOT_IMPLEMENTED, messageOr(e, "Not Implemented"), e);
       } catch (UpdateException e) {
+        cause = Optional.of(e);
         Throwable t = e.getCause();
         if (t instanceof LockFailureException) {
           logger.atSevere().withCause(t).log("Error in %s %s", req.getMethod(), uriForLogging(req));
           responseBytes = replyError(req, res, status = SC_SERVICE_UNAVAILABLE, "Lock failure", e);
         } else {
           status = SC_INTERNAL_SERVER_ERROR;
-          responseBytes = handleException(e, req, res);
+          responseBytes = handleException(traceContext, e, req, res);
         }
       } catch (QuotaException e) {
+        cause = Optional.of(e);
         responseBytes =
             replyError(
                 req,
@@ -658,14 +679,15 @@
                 e.caching(),
                 e);
       } catch (Exception e) {
+        cause = Optional.of(e);
         status = SC_INTERNAL_SERVER_ERROR;
-        responseBytes = handleException(e, req, res);
+        responseBytes = handleException(traceContext, e, req, res);
       } finally {
-        String metric =
-            viewData != null && viewData.view != null ? globals.metrics.view(viewData) : "_unknown";
+        String metric = getViewName(viewData);
+        String formattedCause = cause.map(globals.retryHelper::formatCause).orElse("_none");
         globals.metrics.count.increment(metric);
         if (status >= SC_BAD_REQUEST) {
-          globals.metrics.errorCount.increment(metric, status);
+          globals.metrics.errorCount.increment(metric, status, formattedCause);
         }
         if (responseBytes != -1) {
           globals.metrics.responseBytes.record(metric, responseBytes);
@@ -688,6 +710,145 @@
     }
   }
 
+  private RestResource parseResourceWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      @Nullable String pluginName,
+      RestCollection<RestResource, RestResource> restCollection,
+      RestResource parentResource,
+      IdString id)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        globals.metrics.view(restCollection.getClass(), pluginName) + "#parse",
+        ActionType.REST_READ_REQUEST,
+        () -> restCollection.parse(parentResource, id));
+  }
+
+  private Response<?> invokeRestReadViewWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      ViewData viewData,
+      RestReadView<RestResource> view,
+      RestResource rsrc)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        getViewName(viewData),
+        ActionType.REST_READ_REQUEST,
+        () -> view.apply(rsrc));
+  }
+
+  private Response<?> invokeRestModifyViewWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      ViewData viewData,
+      RestModifyView<RestResource, Object> view,
+      RestResource rsrc,
+      Object inputRequestBody)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        getViewName(viewData),
+        ActionType.REST_WRITE_REQUEST,
+        () -> view.apply(rsrc, inputRequestBody));
+  }
+
+  private Response<?> invokeRestCollectionCreateViewWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      ViewData viewData,
+      RestCollectionCreateView<RestResource, RestResource, Object> view,
+      RestResource rsrc,
+      IdString path,
+      Object inputRequestBody)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        getViewName(viewData),
+        ActionType.REST_WRITE_REQUEST,
+        () -> view.apply(rsrc, path, inputRequestBody));
+  }
+
+  private Response<?> invokeRestCollectionDeleteMissingViewWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      ViewData viewData,
+      RestCollectionDeleteMissingView<RestResource, RestResource, Object> view,
+      RestResource rsrc,
+      IdString path,
+      Object inputRequestBody)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        getViewName(viewData),
+        ActionType.REST_WRITE_REQUEST,
+        () -> view.apply(rsrc, path, inputRequestBody));
+  }
+
+  private Response<?> invokeRestCollectionModifyViewWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      ViewData viewData,
+      RestCollectionModifyView<RestResource, RestResource, Object> view,
+      RestResource rsrc,
+      Object inputRequestBody)
+      throws Exception {
+    return invokeRestEndpointWithRetry(
+        req,
+        traceContext,
+        getViewName(viewData),
+        ActionType.REST_WRITE_REQUEST,
+        () -> view.apply(rsrc, inputRequestBody));
+  }
+
+  private <T> T invokeRestEndpointWithRetry(
+      HttpServletRequest req,
+      TraceContext traceContext,
+      String caller,
+      ActionType actionType,
+      Action<T> action)
+      throws Exception {
+    AtomicReference<Optional<String>> traceId = new AtomicReference<>(Optional.empty());
+    RetryHelper.Options.Builder retryOptionsBuilder = RetryHelper.options().caller(caller);
+    if (!traceContext.isTracing()) {
+      // enable automatic retry with tracing in case of non-recoverable failure
+      retryOptionsBuilder =
+          retryOptionsBuilder
+              .retryWithTrace(t -> !(t instanceof RestApiException))
+              .onAutoTrace(
+                  autoTraceId -> {
+                    traceId.set(Optional.of(autoTraceId));
+
+                    // Include details of the request into the trace.
+                    traceRequestData(req);
+                  });
+    }
+    try {
+      // ExceptionHookImpl controls on which exceptions we retry.
+      // The passed in exceptionPredicate allows to define additional exceptions on which retry
+      // should happen, but here we have none (hence pass in "t -> false" as exceptionPredicate).
+      return globals.retryHelper.execute(
+          actionType, action, retryOptionsBuilder.build(), t -> false);
+    } finally {
+      // If auto-tracing got triggered due to a non-recoverable failure, also trace the rest of
+      // this request. This means logging is forced for all further log statements and the logs are
+      // associated with the same trace ID.
+      traceId
+          .get()
+          .ifPresent(tid -> traceContext.addTag(RequestId.Type.TRACE_ID, tid).forceLogging());
+    }
+  }
+
+  private String getViewName(ViewData viewData) {
+    return viewData != null && viewData.view != null ? globals.metrics.view(viewData) : "_unknown";
+  }
+
   private static HttpServletRequest applyXdOverrides(HttpServletRequest req, QueryParams qp)
       throws BadRequestException {
     if (!isPost(req)) {
@@ -1451,6 +1612,15 @@
     return requestInfo.build();
   }
 
+  private void traceRequestData(HttpServletRequest req) {
+    logger.atFinest().log(
+        "Received REST request: %s %s (parameters: %s)",
+        req.getMethod(), req.getRequestURI(), getParameterNames(req));
+    logger.atFinest().log("Calling user: %s", globals.currentUser.get().getLoggableName());
+    logger.atFinest().log(
+        "Groups: %s", globals.currentUser.get().getEffectiveGroups().getKnownGroups());
+  }
+
   private boolean isDelete(HttpServletRequest req) {
     return "DELETE".equals(req.getMethod());
   }
@@ -1493,13 +1663,25 @@
     }
   }
 
-  private long handleException(Throwable err, HttpServletRequest req, HttpServletResponse res)
+  private long handleException(
+      TraceContext traceContext, Throwable err, HttpServletRequest req, HttpServletResponse res)
       throws IOException {
     logger.atSevere().withCause(err).log("Error in %s %s", req.getMethod(), uriForLogging(req));
     if (!res.isCommitted()) {
       res.reset();
-      traceId.ifPresent(traceId -> res.addHeader(X_GERRIT_TRACE, traceId));
-      return replyError(req, res, SC_INTERNAL_SERVER_ERROR, "Internal server error", err);
+      traceContext.getTraceId().ifPresent(traceId -> res.addHeader(X_GERRIT_TRACE, traceId));
+      StringBuilder msg = new StringBuilder("Internal server error");
+      ImmutableList<String> userMessages =
+          globals.exceptionHooks.stream()
+              .map(h -> h.getUserMessage(err))
+              .filter(Optional::isPresent)
+              .map(Optional::get)
+              .collect(toImmutableList());
+      if (!userMessages.isEmpty()) {
+        msg.append("\n");
+        userMessages.forEach(m -> msg.append("\n* ").append(m));
+      }
+      return replyError(req, res, SC_INTERNAL_SERVER_ERROR, msg.toString(), err);
     }
     return 0;
   }
diff --git a/java/com/google/gerrit/index/Schema.java b/java/com/google/gerrit/index/Schema.java
index f9f8c48..0aa374b 100644
--- a/java/com/google/gerrit/index/Schema.java
+++ b/java/com/google/gerrit/index/Schema.java
@@ -15,11 +15,12 @@
 package com.google.gerrit.index;
 
 import static com.google.common.base.Preconditions.checkState;
+import static com.google.common.collect.ImmutableList.toImmutableList;
 
 import com.google.common.base.MoreObjects;
-import com.google.common.collect.FluentIterable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.flogger.FluentLogger;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -181,12 +182,17 @@
    * <p>Null values are omitted, as are fields which cause errors, which are logged.
    *
    * @param obj input object.
+   * @param skipFields set of field names to skip when indexing the document
    * @return all non-null field values from the object.
    */
-  public final Iterable<Values<T>> buildFields(T obj) {
-    return FluentIterable.from(fields.values())
-        .transform(
+  public final Iterable<Values<T>> buildFields(T obj, ImmutableSet<String> skipFields) {
+    return fields.values().stream()
+        .map(
             f -> {
+              if (skipFields.contains(f.getName())) {
+                return null;
+              }
+
               Object v;
               try {
                 v = f.get(obj);
@@ -203,7 +209,8 @@
                 return new Values<>(f, Collections.singleton(v));
               }
             })
-        .filter(Objects::nonNull);
+        .filter(Objects::nonNull)
+        .collect(toImmutableList());
   }
 
   @Override
diff --git a/java/com/google/gerrit/index/query/QueryBuilder.java b/java/com/google/gerrit/index/query/QueryBuilder.java
index d24cfeb..85dcf3e 100644
--- a/java/com/google/gerrit/index/query/QueryBuilder.java
+++ b/java/com/google/gerrit/index/query/QueryBuilder.java
@@ -29,6 +29,7 @@
 
 import com.google.common.base.Ascii;
 import com.google.common.base.CharMatcher;
+import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableMap;
 import com.google.gerrit.common.Nullable;
@@ -42,7 +43,9 @@
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import org.antlr.runtime.tree.Tree;
 
 /**
@@ -184,6 +187,7 @@
 
   protected final Definition<T, Q> builderDef;
   private final ImmutableMap<String, OperatorFactory<T, Q>> opFactories;
+  protected Map<String, String> opAliases = Collections.emptyMap();
 
   protected QueryBuilder(
       Definition<T, Q> def,
@@ -220,6 +224,10 @@
     return toPredicate(QueryParser.parse(query));
   }
 
+  public void setOperatorAliases(Map<String, String> opAliases) {
+    this.opAliases = opAliases;
+  }
+
   /**
    * Parse multiple user-supplied query strings into a list of predicates.
    *
@@ -290,8 +298,12 @@
 
   @SuppressWarnings("unchecked")
   private Predicate<T> operator(String name, String value) throws QueryParseException {
+    String opName = MoreObjects.firstNonNull(opAliases.get(name), name);
     @SuppressWarnings("rawtypes")
-    OperatorFactory f = opFactories.get(name);
+    OperatorFactory f = opFactories.get(opName);
+    if (f == null && !opName.equals(name)) {
+      f = opFactories.get(name);
+    }
     if (f == null) {
       throw error("Unsupported operator " + name + ":" + value);
     }
diff --git a/java/com/google/gerrit/index/query/QueryProcessor.java b/java/com/google/gerrit/index/query/QueryProcessor.java
index 9501e52..c05516b 100644
--- a/java/com/google/gerrit/index/query/QueryProcessor.java
+++ b/java/com/google/gerrit/index/query/QueryProcessor.java
@@ -18,7 +18,7 @@
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.flogger.LazyArgs.lazy;
-import static java.util.stream.Collectors.toSet;
+import static java.util.stream.Collectors.toList;
 
 import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableList;
@@ -272,7 +272,7 @@
         ImmutableList<T> matchesList = matches.get(i).toList();
         logger.atFine().log(
             "Matches[%d]:\n%s",
-            i, lazy(() -> matchesList.stream().map(this::formatForLogging).collect(toSet())));
+            i, lazy(() -> matchesList.stream().map(this::formatForLogging).collect(toList())));
         out.add(
             QueryResult.create(
                 queryStrings != null ? queryStrings.get(i) : null,
diff --git a/java/com/google/gerrit/index/query/RangeUtil.java b/java/com/google/gerrit/index/query/RangeUtil.java
index 1f22f36..cfe1929 100644
--- a/java/com/google/gerrit/index/query/RangeUtil.java
+++ b/java/com/google/gerrit/index/query/RangeUtil.java
@@ -106,6 +106,10 @@
         break;
     }
 
+    // Ensure that minValue <= min/max <= maxValue.
+    min = Ints.constrainToRange(min, minValue, maxValue);
+    max = Ints.constrainToRange(max, minValue, maxValue);
+
     return new Range(prefix, min, max);
   }
 
diff --git a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
index deb3203..5392ab4 100644
--- a/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
+++ b/java/com/google/gerrit/lucene/AbstractLuceneIndex.java
@@ -21,6 +21,7 @@
 import com.google.common.base.Joiner;
 import com.google.common.collect.ArrayListMultimap;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Sets;
 import com.google.common.flogger.FluentLogger;
@@ -98,6 +99,7 @@
   private final SitePaths sitePaths;
   private final Directory dir;
   private final String name;
+  private final ImmutableSet<String> skipFields;
   private final ListeningExecutorService writerThread;
   private final IndexWriter writer;
   private final ReferenceManager<IndexSearcher> searcherManager;
@@ -110,6 +112,7 @@
       SitePaths sitePaths,
       Directory dir,
       String name,
+      ImmutableSet<String> skipFields,
       String subIndex,
       GerritIndexWriterConfig writerConfig,
       SearcherFactory searcherFactory)
@@ -118,6 +121,7 @@
     this.sitePaths = sitePaths;
     this.dir = dir;
     this.name = name;
+    this.skipFields = skipFields;
     String index = Joiner.on('_').skipNulls().join(name, subIndex);
     long commitPeriod = writerConfig.getCommitWithinMs();
 
@@ -311,7 +315,7 @@
 
   Document toDocument(V obj) {
     Document result = new Document();
-    for (Values<V> vs : schema.buildFields(obj)) {
+    for (Values<V> vs : schema.buildFields(obj, skipFields)) {
       if (vs.getValues() != null) {
         add(result, vs);
       }
diff --git a/java/com/google/gerrit/lucene/ChangeSubIndex.java b/java/com/google/gerrit/lucene/ChangeSubIndex.java
index fd439f1..e51a91a7 100644
--- a/java/com/google/gerrit/lucene/ChangeSubIndex.java
+++ b/java/com/google/gerrit/lucene/ChangeSubIndex.java
@@ -20,6 +20,7 @@
 import static com.google.gerrit.lucene.LuceneChangeIndex.UPDATED_SORT_FIELD;
 import static com.google.gerrit.server.index.change.ChangeSchemaDefinitions.NAME;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.index.FieldDef;
 import com.google.gerrit.index.QueryOptions;
@@ -48,6 +49,7 @@
       Schema<ChangeData> schema,
       SitePaths sitePaths,
       Path path,
+      ImmutableSet<String> skipFields,
       GerritIndexWriterConfig writerConfig,
       SearcherFactory searcherFactory)
       throws IOException {
@@ -56,6 +58,7 @@
         sitePaths,
         FSDirectory.open(path),
         path.getFileName().toString(),
+        skipFields,
         writerConfig,
         searcherFactory);
   }
@@ -65,10 +68,11 @@
       SitePaths sitePaths,
       Directory dir,
       String subIndex,
+      ImmutableSet<String> skipFields,
       GerritIndexWriterConfig writerConfig,
       SearcherFactory searcherFactory)
       throws IOException {
-    super(schema, sitePaths, dir, NAME, subIndex, writerConfig, searcherFactory);
+    super(schema, sitePaths, dir, NAME, skipFields, subIndex, writerConfig, searcherFactory);
   }
 
   @Override
diff --git a/java/com/google/gerrit/lucene/LuceneAccountIndex.java b/java/com/google/gerrit/lucene/LuceneAccountIndex.java
index efd7ea3..242cffd 100644
--- a/java/com/google/gerrit/lucene/LuceneAccountIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneAccountIndex.java
@@ -20,6 +20,7 @@
 import static com.google.gerrit.server.index.account.AccountField.ID_STR;
 import static com.google.gerrit.server.index.account.AccountField.PREFERRED_EMAIL_EXACT;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.index.FieldDef;
@@ -100,6 +101,7 @@
         sitePaths,
         dir(schema, cfg, sitePaths),
         ACCOUNTS,
+        ImmutableSet.of(),
         null,
         new GerritIndexWriterConfig(cfg, ACCOUNTS),
         new SearcherFactory());
diff --git a/java/com/google/gerrit/lucene/LuceneChangeIndex.java b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
index 16d66b6..3b277dd 100644
--- a/java/com/google/gerrit/lucene/LuceneChangeIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneChangeIndex.java
@@ -29,6 +29,7 @@
 import com.google.common.collect.Collections2;
 import com.google.common.collect.FluentIterable;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.MultimapBuilder;
@@ -167,6 +168,7 @@
   private final String idSortFieldName;
   private final IdTerm idTerm;
   private final ChangeIdExtractor extractor;
+  private final ImmutableSet<String> skipFields;
 
   @Inject
   LuceneChangeIndex(
@@ -179,6 +181,10 @@
     this.executor = executor;
     this.changeDataFactory = changeDataFactory;
     this.schema = schema;
+    this.skipFields =
+        cfg.getBoolean("index", "change", "indexMergeable", true)
+            ? ImmutableSet.of()
+            : ImmutableSet.of(ChangeField.MERGEABLE.getName());
 
     GerritIndexWriterConfig openConfig = new GerritIndexWriterConfig(cfg, "changes_open");
     GerritIndexWriterConfig closedConfig = new GerritIndexWriterConfig(cfg, "changes_closed");
@@ -189,18 +195,40 @@
     if (LuceneIndexModule.isInMemoryTest(cfg)) {
       openIndex =
           new ChangeSubIndex(
-              schema, sitePaths, new RAMDirectory(), "ramOpen", openConfig, searcherFactory);
+              schema,
+              sitePaths,
+              new RAMDirectory(),
+              "ramOpen",
+              skipFields,
+              openConfig,
+              searcherFactory);
       closedIndex =
           new ChangeSubIndex(
-              schema, sitePaths, new RAMDirectory(), "ramClosed", closedConfig, searcherFactory);
+              schema,
+              sitePaths,
+              new RAMDirectory(),
+              "ramClosed",
+              skipFields,
+              closedConfig,
+              searcherFactory);
     } else {
       Path dir = LuceneVersionManager.getDir(sitePaths, CHANGES, schema);
       openIndex =
           new ChangeSubIndex(
-              schema, sitePaths, dir.resolve(CHANGES_OPEN), openConfig, searcherFactory);
+              schema,
+              sitePaths,
+              dir.resolve(CHANGES_OPEN),
+              skipFields,
+              openConfig,
+              searcherFactory);
       closedIndex =
           new ChangeSubIndex(
-              schema, sitePaths, dir.resolve(CHANGES_CLOSED), closedConfig, searcherFactory);
+              schema,
+              sitePaths,
+              dir.resolve(CHANGES_CLOSED),
+              skipFields,
+              closedConfig,
+              searcherFactory);
     }
 
     idField = this.schema.useLegacyNumericFields() ? LEGACY_ID : LEGACY_ID_STR;
@@ -565,7 +593,7 @@
 
   private void decodeMergeable(ListMultimap<String, IndexableField> doc, ChangeData cd) {
     IndexableField f = Iterables.getFirst(doc.get(MERGEABLE_FIELD), null);
-    if (f != null) {
+    if (f != null && !skipFields.contains(MERGEABLE_FIELD)) {
       String mergeable = f.stringValue();
       if ("1".equals(mergeable)) {
         cd.setMergeable(true);
diff --git a/java/com/google/gerrit/lucene/LuceneGroupIndex.java b/java/com/google/gerrit/lucene/LuceneGroupIndex.java
index 99cd40d..3d1d471 100644
--- a/java/com/google/gerrit/lucene/LuceneGroupIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneGroupIndex.java
@@ -17,6 +17,7 @@
 import static com.google.common.collect.Iterables.getOnlyElement;
 import static com.google.gerrit.server.index.group.GroupField.UUID;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.AccountGroup;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.index.FieldDef;
@@ -90,6 +91,7 @@
         sitePaths,
         dir(schema, cfg, sitePaths),
         GROUPS,
+        ImmutableSet.of(),
         null,
         new GerritIndexWriterConfig(cfg, GROUPS),
         new SearcherFactory());
diff --git a/java/com/google/gerrit/lucene/LuceneProjectIndex.java b/java/com/google/gerrit/lucene/LuceneProjectIndex.java
index 97454c7..a3a0d9c 100644
--- a/java/com/google/gerrit/lucene/LuceneProjectIndex.java
+++ b/java/com/google/gerrit/lucene/LuceneProjectIndex.java
@@ -17,6 +17,7 @@
 import static com.google.common.collect.Iterables.getOnlyElement;
 import static com.google.gerrit.index.project.ProjectField.NAME;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.index.FieldDef;
@@ -90,6 +91,7 @@
         sitePaths,
         dir(schema, cfg, sitePaths),
         PROJECTS,
+        ImmutableSet.of(),
         null,
         new GerritIndexWriterConfig(cfg, PROJECTS),
         new SearcherFactory());
diff --git a/java/com/google/gerrit/pgm/Daemon.java b/java/com/google/gerrit/pgm/Daemon.java
index e6860c2..568fb60 100644
--- a/java/com/google/gerrit/pgm/Daemon.java
+++ b/java/com/google/gerrit/pgm/Daemon.java
@@ -109,6 +109,7 @@
 import com.google.gerrit.sshd.SshModule;
 import com.google.gerrit.sshd.commands.DefaultCommandModule;
 import com.google.gerrit.sshd.commands.IndexCommandsModule;
+import com.google.gerrit.sshd.commands.SequenceCommandsModule;
 import com.google.gerrit.sshd.plugin.LfsPluginAuthCommand;
 import com.google.inject.AbstractModule;
 import com.google.inject.Guice;
@@ -517,6 +518,7 @@
             sysInjector.getInstance(LfsPluginAuthCommand.Module.class)));
     if (!replica) {
       modules.add(new IndexCommandsModule(sysInjector));
+      modules.add(new SequenceCommandsModule());
     }
     return sysInjector.createChildInjector(modules);
   }
diff --git a/java/com/google/gerrit/pgm/http/jetty/JettyServer.java b/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
index 22bc21d..096e4a1 100644
--- a/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
+++ b/java/com/google/gerrit/pgm/http/jetty/JettyServer.java
@@ -36,8 +36,10 @@
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.EnumSet;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.TimeUnit;
 import javax.servlet.DispatcherType;
@@ -411,10 +413,20 @@
         Class<? extends Filter> filterClass =
             (Class<? extends Filter>) Class.forName(filterClassName);
         Filter filter = env.webInjector.getInstance(filterClass);
-        app.addFilter(
-            new FilterHolder(filter),
-            "/*",
-            EnumSet.of(DispatcherType.REQUEST, DispatcherType.ASYNC));
+
+        Map<String, String> initParams = new HashMap<>();
+        Set<String> initParamKeys = cfg.getNames("filterClass", filterClassName, true);
+        initParamKeys.forEach(
+            paramKey -> {
+              String paramValue = cfg.getString("filterClass", filterClassName, paramKey);
+              initParams.put(paramKey, paramValue);
+            });
+
+        FilterHolder filterHolder = new FilterHolder(filter);
+        if (initParams.size() > 0) {
+          filterHolder.setInitParameters(initParams);
+        }
+        app.addFilter(filterHolder, "/*", EnumSet.of(DispatcherType.REQUEST, DispatcherType.ASYNC));
       } catch (Throwable e) {
         throw new IllegalArgumentException(
             "Unable to instantiate front-end HTTP Filter " + filterClassName, e);
diff --git a/java/com/google/gerrit/pgm/http/jetty/ProjectQoSFilter.java b/java/com/google/gerrit/pgm/http/jetty/ProjectQoSFilter.java
index 9354209..4f9d7e7 100644
--- a/java/com/google/gerrit/pgm/http/jetty/ProjectQoSFilter.java
+++ b/java/com/google/gerrit/pgm/http/jetty/ProjectQoSFilter.java
@@ -34,6 +34,10 @@
 import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import javax.servlet.AsyncContext;
+import javax.servlet.AsyncEvent;
+import javax.servlet.AsyncListener;
+import javax.servlet.DispatcherType;
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -43,16 +47,13 @@
 import javax.servlet.ServletResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.eclipse.jetty.continuation.Continuation;
-import org.eclipse.jetty.continuation.ContinuationListener;
-import org.eclipse.jetty.continuation.ContinuationSupport;
 import org.eclipse.jgit.lib.Config;
 
 /**
- * Use Jetty continuations to defer execution until threads are available.
+ * Use AsyncContexts to defer execution until threads are available.
  *
  * <p>We actually schedule a task into the same execution queue as the SSH daemon uses for command
- * execution, and then park the web request in a continuation until an execution thread is
+ * execution, and then park the web request in an AsyncContext until an execution thread is
  * available. This ensures that the overall JVM process doesn't exceed the configured limit on
  * concurrent Git requests.
  *
@@ -61,12 +62,10 @@
  * Jetty's HTTP parser to crash, so we instead block the SSH execution queue thread and ask Jetty to
  * resume processing on the web service thread.
  */
-@SuppressWarnings("deprecation")
 @Singleton
 public class ProjectQoSFilter implements Filter {
-  private static final String ATT_SPACE = ProjectQoSFilter.class.getName();
-  private static final String TASK = ATT_SPACE + "/TASK";
-  private static final String CANCEL = ATT_SPACE + "/CANCEL";
+  private static final String ATT_SPACE = ProjectQoSFilter.class.getName() + "/";
+  private static final String TASK = ATT_SPACE + "TASK";
 
   private static final String FILTER_RE = "^/(.*)/(git-upload-pack|git-receive-pack)$";
   private static final Pattern URI_PATTERN = Pattern.compile(FILTER_RE);
@@ -79,6 +78,59 @@
     }
   }
 
+  public enum RequestState {
+    INITIAL,
+    SUSPENDED,
+    RESUMED,
+    CANCELED,
+    UNEXPECTED;
+
+    private static final String CANCELED_ATT = ATT_SPACE + CANCELED;
+    private static final String SUSPENDED_ATT = ATT_SPACE + SUSPENDED;
+    private static final String RESUMED_ATT = ATT_SPACE + RESUMED;
+
+    private void set(ServletRequest req) {
+      switch (this) {
+        case SUSPENDED:
+          req.setAttribute(SUSPENDED_ATT, true);
+          req.setAttribute(RESUMED_ATT, false);
+          break;
+        case CANCELED:
+          req.setAttribute(CANCELED_ATT, true);
+          break;
+        case RESUMED:
+          req.setAttribute(RESUMED_ATT, true);
+          break;
+        case INITIAL:
+        case UNEXPECTED:
+        default:
+          break;
+      }
+    }
+
+    private static RequestState get(ServletRequest req) {
+      if (Boolean.FALSE.equals(req.getAttribute(RESUMED_ATT))
+          && Boolean.TRUE.equals(req.getAttribute(SUSPENDED_ATT))) {
+        return SUSPENDED;
+      }
+
+      if (req.getDispatcherType() != DispatcherType.ASYNC) {
+        return INITIAL;
+      }
+
+      if (Boolean.TRUE.equals(req.getAttribute(RESUMED_ATT))
+          && Boolean.TRUE.equals(req.getAttribute(CANCELED_ATT))) {
+        return CANCELED;
+      }
+
+      if (Boolean.TRUE.equals(req.getAttribute(RESUMED_ATT))) {
+        return RESUMED;
+      }
+
+      return UNEXPECTED;
+    }
+  }
+
   private final AccountLimits.Factory limitsFactory;
   private final Provider<CurrentUser> user;
   private final QueueProvider queue;
@@ -104,40 +156,50 @@
       throws IOException, ServletException {
     final HttpServletRequest req = (HttpServletRequest) request;
     final HttpServletResponse rsp = (HttpServletResponse) response;
-    final Continuation cont = ContinuationSupport.getContinuation(req);
 
-    if (cont.isInitial()) {
-      TaskThunk task = new TaskThunk(cont, req);
-      if (maxWait > 0) {
-        cont.setTimeout(maxWait);
-      }
-      cont.suspend(rsp);
-      cont.setAttribute(TASK, task);
+    final TaskThunk task;
 
-      Future<?> f = getExecutor().submit(task);
-      cont.addContinuationListener(new Listener(f));
-    } else if (cont.isExpired()) {
-      rsp.sendError(SC_SERVICE_UNAVAILABLE);
+    switch (RequestState.get(request)) {
+      case INITIAL:
+        AsyncContext asyncContext = suspend(request);
+        task = new TaskThunk(asyncContext, req);
+        if (maxWait > 0) {
+          asyncContext.setTimeout(maxWait);
+        }
 
-    } else if (cont.isResumed() && cont.getAttribute(CANCEL) == Boolean.TRUE) {
-      rsp.sendError(SC_SERVICE_UNAVAILABLE);
+        request.setAttribute(TASK, task);
 
-    } else if (cont.isResumed()) {
-      TaskThunk task = (TaskThunk) cont.getAttribute(TASK);
-      try {
-        task.begin(Thread.currentThread());
-        chain.doFilter(req, rsp);
-      } finally {
-        task.end();
-        Thread.interrupted();
-      }
-
-    } else {
-      context.log("Unexpected QoS continuation state, aborting request");
-      rsp.sendError(SC_SERVICE_UNAVAILABLE);
+        Future<?> f = getExecutor().submit(task);
+        asyncContext.addListener(new Listener(f));
+        break;
+      case CANCELED:
+        rsp.sendError(SC_SERVICE_UNAVAILABLE);
+        break;
+      case RESUMED:
+        task = (TaskThunk) request.getAttribute(TASK);
+        try {
+          task.begin(Thread.currentThread());
+          chain.doFilter(req, rsp);
+        } finally {
+          task.end();
+          Thread.interrupted();
+        }
+        break;
+      case SUSPENDED:
+      case UNEXPECTED:
+      default:
+        context.log("Unexpected QoS state, aborting request");
+        rsp.sendError(SC_SERVICE_UNAVAILABLE);
+        break;
     }
   }
 
+  private AsyncContext suspend(ServletRequest request) {
+    AsyncContext asyncContext = request.startAsync();
+    RequestState.SUSPENDED.set(request);
+    return asyncContext;
+  }
+
   private ScheduledThreadPoolExecutor getExecutor() {
     QueueProvider.QueueType qt = limitsFactory.create(user.get()).getQueueType();
     return queue.getQueue(qt);
@@ -149,7 +211,7 @@
   @Override
   public void destroy() {}
 
-  private static final class Listener implements ContinuationListener {
+  private static final class Listener implements AsyncListener {
     final Future<?> future;
 
     Listener(Future<?> future) {
@@ -157,29 +219,35 @@
     }
 
     @Override
-    public void onComplete(Continuation self) {}
+    public void onComplete(AsyncEvent event) throws IOException {}
 
     @Override
-    public void onTimeout(Continuation self) {
+    public void onTimeout(AsyncEvent event) throws IOException {
       future.cancel(true);
     }
+
+    @Override
+    public void onError(AsyncEvent event) throws IOException {}
+
+    @Override
+    public void onStartAsync(AsyncEvent event) throws IOException {}
   }
 
   private final class TaskThunk implements CancelableRunnable {
-    private final Continuation cont;
+    private final AsyncContext asyncContext;
     private final String name;
     private final Object lock = new Object();
     private boolean done;
     private Thread worker;
 
-    TaskThunk(Continuation cont, HttpServletRequest req) {
-      this.cont = cont;
+    TaskThunk(AsyncContext asyncContext, HttpServletRequest req) {
+      this.asyncContext = asyncContext;
       this.name = generateName(req);
     }
 
     @Override
     public void run() {
-      cont.resume();
+      resume();
 
       synchronized (lock) {
         while (!done) {
@@ -212,8 +280,16 @@
 
     @Override
     public void cancel() {
-      cont.setAttribute(CANCEL, Boolean.TRUE);
-      cont.resume();
+      RequestState.CANCELED.set(asyncContext.getRequest());
+      resume();
+    }
+
+    private void resume() {
+      ServletRequest req = asyncContext.getRequest();
+      if (RequestState.SUSPENDED.equals(RequestState.get(req))) {
+        RequestState.RESUMED.set(req);
+        asyncContext.dispatch();
+      }
     }
 
     @Override
diff --git a/java/com/google/gerrit/server/BUILD b/java/com/google/gerrit/server/BUILD
index 6675595..45d037a 100644
--- a/java/com/google/gerrit/server/BUILD
+++ b/java/com/google/gerrit/server/BUILD
@@ -54,6 +54,7 @@
         "//java/com/google/gerrit/prettify:server",
         "//java/com/google/gerrit/proto",
         "//java/com/google/gerrit/server/cache/serialize",
+        "//java/com/google/gerrit/server/git/receive:ref_cache",
         "//java/com/google/gerrit/server/ioutil",
         "//java/com/google/gerrit/server/logging",
         "//java/com/google/gerrit/server/util/git",
@@ -106,12 +107,12 @@
         "//lib/auto:auto-value-annotations",
         "//lib/bouncycastle:bcpkix-neverlink",
         "//lib/bouncycastle:bcprov-neverlink",
-        "//lib/commons:codec",
         "//lib/commons:compress",
         "//lib/commons:dbcp",
         "//lib/commons:lang",
         "//lib/commons:net",
         "//lib/commons:validator",
+        "//lib/errorprone:annotations",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/guice:guice-assistedinject",
diff --git a/java/com/google/gerrit/server/ChangeUtil.java b/java/com/google/gerrit/server/ChangeUtil.java
index ee82a26..a166d97 100644
--- a/java/com/google/gerrit/server/ChangeUtil.java
+++ b/java/com/google/gerrit/server/ChangeUtil.java
@@ -25,7 +25,6 @@
 import java.io.IOException;
 import java.security.SecureRandom;
 import java.util.Collection;
-import java.util.Map;
 import java.util.Random;
 import java.util.Set;
 import java.util.stream.Stream;
@@ -50,22 +49,6 @@
   }
 
   /**
-   * Get the next patch set ID from a previously-read map of all refs.
-   *
-   * @param allRefs map of full ref name to ref.
-   * @param id previous patch set ID.
-   * @return next unused patch set ID for the same change, skipping any IDs whose corresponding ref
-   *     names appear in the {@code allRefs} map.
-   */
-  public static PatchSet.Id nextPatchSetIdFromAllRefsMap(Map<String, Ref> allRefs, PatchSet.Id id) {
-    PatchSet.Id next = nextPatchSetId(id);
-    while (allRefs.containsKey(next.toRefName())) {
-      next = nextPatchSetId(next);
-    }
-    return next;
-  }
-
-  /**
    * Get the next patch set ID from a previously-read map of refs below the change prefix.
    *
    * @param changeRefNames existing full change ref names with the same change ID as {@code id}.
@@ -95,9 +78,7 @@
   /**
    * Get the next patch set ID just looking at a single previous patch set ID.
    *
-   * <p>This patch set ID may or may not be available in the database; callers that want a
-   * previously-unused ID should use {@link #nextPatchSetIdFromAllRefsMap} or {@link
-   * #nextPatchSetIdFromChangeRefs}.
+   * <p>This patch set ID may or may not be available in the database.
    *
    * @param id previous patch set ID.
    * @return next patch set ID for the same change, incrementing by 1.
diff --git a/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java b/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
index 996257c..5e7919f 100644
--- a/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
+++ b/java/com/google/gerrit/server/CreateGroupPermissionSyncer.java
@@ -115,11 +115,12 @@
                 .collect(toList()));
         config.replace(createGroupAccessSection);
       } else {
-        Permission createGroupPermission = new Permission(Permission.CREATE);
-        createGroupAccessSection.addPermission(createGroupPermission);
-        createGroupsGlobal.forEach(createGroupPermission::add);
         // The create permission is managed by Gerrit at this point only so there is no concern of
         // overwriting user-defined permissions here.
+        Permission createGroupPermission = new Permission(Permission.CREATE);
+        createGroupAccessSection.remove(createGroupPermission);
+        createGroupAccessSection.addPermission(createGroupPermission);
+        createGroupsGlobal.forEach(createGroupPermission::add);
         config.replace(createGroupAccessSection);
       }
 
diff --git a/java/com/google/gerrit/server/ExceptionHook.java b/java/com/google/gerrit/server/ExceptionHook.java
index ea76330..db44b4b 100644
--- a/java/com/google/gerrit/server/ExceptionHook.java
+++ b/java/com/google/gerrit/server/ExceptionHook.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.server;
 
 import com.google.gerrit.extensions.annotations.ExtensionPoint;
+import java.util.Optional;
 
 /**
  * Allows implementors to control how certain exceptions should be handled.
@@ -39,4 +40,28 @@
   default boolean shouldRetry(Throwable throwable) {
     return false;
   }
+
+  /**
+   * Formats the cause of an exception for use in metrics.
+   *
+   * <p>This method allows implementors to group exceptions that have the same cause into one metric
+   * bucket.
+   *
+   * @param throwable the exception cause
+   * @return formatted cause or {@link Optional#empty()} if no formatting was done
+   */
+  default Optional<String> formatCause(Throwable throwable) {
+    return Optional.empty();
+  }
+
+  /**
+   * Returns an error message that should be returned to the user.
+   *
+   * @param throwable throwable that was thrown while executing an operation
+   * @return error message that should be returned to the user, {@link Optional#empty()} if no
+   *     message should be returned to the user
+   */
+  default Optional<String> getUserMessage(Throwable throwable) {
+    return Optional.empty();
+  }
 }
diff --git a/java/com/google/gerrit/server/ExceptionHookImpl.java b/java/com/google/gerrit/server/ExceptionHookImpl.java
new file mode 100644
index 0000000..9613b29
--- /dev/null
+++ b/java/com/google/gerrit/server/ExceptionHookImpl.java
@@ -0,0 +1,68 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server;
+
+import com.google.common.base.Predicate;
+import com.google.common.base.Throwables;
+import com.google.gerrit.git.LockFailureException;
+import java.util.Optional;
+import org.eclipse.jgit.lib.RefUpdate;
+
+/**
+ * Class to detect and handle exceptions that are caused by temporary errors, and hence should cause
+ * a retry of the failed operation.
+ */
+public class ExceptionHookImpl implements ExceptionHook {
+  private static final String LOCK_FAILURE_USER_MESSAGE =
+      "Updating a ref failed with LOCK_FAILURE.\n"
+          + "This may be a temporary issue due to concurrent updates.\n"
+          + "Please retry later.";
+
+  @Override
+  public boolean shouldRetry(Throwable throwable) {
+    return isLockFailure(throwable);
+  }
+
+  @Override
+  public Optional<String> formatCause(Throwable throwable) {
+    if (isLockFailure(throwable)) {
+      return Optional.of(RefUpdate.Result.LOCK_FAILURE.name());
+    }
+    return Optional.empty();
+  }
+
+  @Override
+  public Optional<String> getUserMessage(Throwable throwable) {
+    if (isLockFailure(throwable)) {
+      return Optional.of(LOCK_FAILURE_USER_MESSAGE);
+    }
+    return Optional.empty();
+  }
+
+  private static boolean isLockFailure(Throwable throwable) {
+    return isMatching(throwable, t -> t instanceof LockFailureException);
+  }
+
+  /**
+   * Check whether the given exception or any of its causes matches the given predicate.
+   *
+   * @param throwable Exception that should be tested
+   * @param predicate predicate to check if a throwable matches
+   * @return {@code true} if the given exception or any of its causes matches the given predicate
+   */
+  private static boolean isMatching(Throwable throwable, Predicate<Throwable> predicate) {
+    return Throwables.getCausalChain(throwable).stream().anyMatch(predicate);
+  }
+}
diff --git a/java/com/google/gerrit/server/PublishCommentUtil.java b/java/com/google/gerrit/server/PublishCommentUtil.java
index 26539c5..f1c2f82 100644
--- a/java/com/google/gerrit/server/PublishCommentUtil.java
+++ b/java/com/google/gerrit/server/PublishCommentUtil.java
@@ -15,12 +15,13 @@
 package com.google.gerrit.server;
 
 import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.gerrit.entities.Comment.Status;
 import static java.util.stream.Collectors.toSet;
 
 import com.google.common.collect.ImmutableList;
+import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.entities.Comment;
+import com.google.gerrit.entities.Comment.Status;
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.extensions.validators.CommentForValidation;
@@ -34,10 +35,14 @@
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.util.Collection;
+import java.util.HashSet;
 import java.util.Map;
+import java.util.Set;
 
 @Singleton
 public class PublishCommentUtil {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
   private final PatchListCache patchListCache;
   private final PatchSetUtil psUtil;
   private final CommentsUtil commentsUtil;
@@ -63,11 +68,32 @@
 
     Map<PatchSet.Id, PatchSet> patchSets =
         psUtil.getAsMap(notes, draftComments.stream().map(d -> psId(notes, d)).collect(toSet()));
+    Set<Comment> commentsToPublish = new HashSet<>();
     for (Comment draftComment : draftComments) {
       PatchSet.Id psIdOfDraftComment = psId(notes, draftComment);
       PatchSet ps = patchSets.get(psIdOfDraftComment);
       if (ps == null) {
-        throw new StorageException("patch set " + psIdOfDraftComment + " not found");
+        // This can happen if changes with the same numeric ID exist:
+        // - change 12345 has 3 patch sets in repo X
+        // - another change 12345 has 7 patch sets in repo Y
+        // - the user saves a draft comment on patch set 6 of the change in repo Y
+        // - this draft comment gets stored in:
+        //   AllUsers -> refs/draft-comments/45/12345/<account-id>
+        // - when posting a review with draft handling PUBLISH_ALL_REVISIONS on the change in
+        //   repo X, the draft comments are loaded from
+        //   AllUsers -> refs/draft-comments/45/12345/<account-id>, including the draft
+        //   comment that was saved for patch set 6 of the change in repo Y
+        // - patch set 6 does not exist for the change in repo x, hence we get null for the patch
+        //   set here
+        // Instead of failing hard (and returning an Internal Server Error) to the caller,
+        // just ignore that comment.
+        // Gerrit ensures that numeric change IDs are unique, but you can get duplicates if
+        // change refs of one repo are copied/pushed to another repo on the same host (this
+        // should never be done, but we know it happens).
+        logger.atWarning().log(
+            "Ignoring draft comment %s on non existing patch set %s (repo = %s)",
+            draftComment, psIdOfDraftComment, notes.getProjectName());
+        continue;
       }
       draftComment.writtenOn = ctx.getWhen();
       draftComment.tag = tag;
@@ -79,8 +105,9 @@
       } catch (PatchListNotAvailableException e) {
         throw new StorageException(e);
       }
+      commentsToPublish.add(draftComment);
     }
-    commentsUtil.putComments(ctx.getUpdate(psId), Status.PUBLISHED, draftComments);
+    commentsUtil.putComments(ctx.getUpdate(psId), Status.PUBLISHED, commentsToPublish);
   }
 
   private static PatchSet.Id psId(ChangeNotes notes, Comment c) {
@@ -98,8 +125,8 @@
     ImmutableList.Builder<CommentValidationFailure> commentValidationFailures =
         new ImmutableList.Builder<>();
     commentValidators.runEach(
-        listener ->
-            commentValidationFailures.addAll(listener.validateComments(commentsForValidation)));
+        validator ->
+            commentValidationFailures.addAll(validator.validateComments(commentsForValidation)));
     return commentValidationFailures.build();
   }
 }
diff --git a/java/com/google/gerrit/server/StarredChangesUtil.java b/java/com/google/gerrit/server/StarredChangesUtil.java
index 5824240..93cf0de 100644
--- a/java/com/google/gerrit/server/StarredChangesUtil.java
+++ b/java/com/google/gerrit/server/StarredChangesUtil.java
@@ -479,8 +479,10 @@
         case FAST_FORWARD:
           gitRefUpdated.fire(allUsers, u, null);
           return;
-        case IO_FAILURE:
         case LOCK_FAILURE:
+          throw new LockFailureException(
+              String.format("Update star labels on ref %s failed", refName), u);
+        case IO_FAILURE:
         case NOT_ATTEMPTED:
         case REJECTED:
         case REJECTED_CURRENT_BRANCH:
@@ -513,11 +515,12 @@
         case FORCED:
           gitRefUpdated.fire(allUsers, u, null);
           return;
+        case LOCK_FAILURE:
+          throw new LockFailureException(String.format("Delete star ref %s failed", refName), u);
         case NEW:
         case NO_CHANGE:
         case FAST_FORWARD:
         case IO_FAILURE:
-        case LOCK_FAILURE:
         case NOT_ATTEMPTED:
         case REJECTED:
         case REJECTED_CURRENT_BRANCH:
diff --git a/java/com/google/gerrit/server/account/AccountResolver.java b/java/com/google/gerrit/server/account/AccountResolver.java
index 988d871..a41a36c 100644
--- a/java/com/google/gerrit/server/account/AccountResolver.java
+++ b/java/com/google/gerrit/server/account/AccountResolver.java
@@ -516,12 +516,22 @@
    * @throws IOException if an error occurs.
    */
   public Result resolve(String input) throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplier(), accountActivityPredicate());
+    return searchImpl(input, searchers, visibilitySupplierCanSee(), accountActivityPredicate());
   }
 
   public Result resolve(String input, Predicate<AccountState> accountActivityPredicate)
       throws ConfigInvalidException, IOException {
-    return searchImpl(input, searchers, visibilitySupplier(), accountActivityPredicate);
+    return searchImpl(input, searchers, visibilitySupplierCanSee(), accountActivityPredicate);
+  }
+
+  public Result resolveIgnoreVisibility(String input) throws ConfigInvalidException, IOException {
+    return searchImpl(input, searchers, visibilitySupplierAll(), accountActivityPredicate());
+  }
+
+  public Result resolveIgnoreVisibility(
+      String input, Predicate<AccountState> accountActivityPredicate)
+      throws ConfigInvalidException, IOException {
+    return searchImpl(input, searchers, visibilitySupplierAll(), accountActivityPredicate);
   }
 
   /**
@@ -550,13 +560,23 @@
   @Deprecated
   public Result resolveByNameOrEmail(String input) throws ConfigInvalidException, IOException {
     return searchImpl(
-        input, nameOrEmailSearchers, visibilitySupplier(), accountActivityPredicate());
+        input, nameOrEmailSearchers, visibilitySupplierCanSee(), accountActivityPredicate());
   }
 
-  private Supplier<Predicate<AccountState>> visibilitySupplier() {
+  private Supplier<Predicate<AccountState>> visibilitySupplierCanSee() {
     return () -> accountControlFactory.get()::canSee;
   }
 
+  private Supplier<Predicate<AccountState>> visibilitySupplierAll() {
+    return () -> all();
+  }
+
+  private Predicate<AccountState> all() {
+    return accountState -> {
+      return true;
+    };
+  }
+
   private Predicate<AccountState> accountActivityPredicate() {
     return (AccountState accountState) -> accountState.account().isActive();
   }
diff --git a/java/com/google/gerrit/server/account/SetInactiveFlag.java b/java/com/google/gerrit/server/account/SetInactiveFlag.java
index fb3d4ea..a6c5d5c 100644
--- a/java/com/google/gerrit/server/account/SetInactiveFlag.java
+++ b/java/com/google/gerrit/server/account/SetInactiveFlag.java
@@ -106,6 +106,6 @@
     if (exception.get().isPresent()) {
       throw exception.get().get();
     }
-    return alreadyActive.get() ? Response.ok("") : Response.created("");
+    return alreadyActive.get() ? Response.ok() : Response.created();
   }
 }
diff --git a/java/com/google/gerrit/server/api/changes/ChangeApiImpl.java b/java/com/google/gerrit/server/api/changes/ChangeApiImpl.java
index a04be30..0d640d9 100644
--- a/java/com/google/gerrit/server/api/changes/ChangeApiImpl.java
+++ b/java/com/google/gerrit/server/api/changes/ChangeApiImpl.java
@@ -48,8 +48,10 @@
 import com.google.gerrit.extensions.common.CommentInfo;
 import com.google.gerrit.extensions.common.CommitMessageInput;
 import com.google.gerrit.extensions.common.Input;
+import com.google.gerrit.extensions.common.InputWithMessage;
 import com.google.gerrit.extensions.common.MergePatchSetInput;
 import com.google.gerrit.extensions.common.PureRevertInfo;
+import com.google.gerrit.extensions.common.RevertSubmissionInfo;
 import com.google.gerrit.extensions.common.RobotCommentInfo;
 import com.google.gerrit.extensions.common.SuggestedReviewerInfo;
 import com.google.gerrit.extensions.registration.DynamicMap;
@@ -62,7 +64,6 @@
 import com.google.gerrit.server.StarredChangesUtil.IllegalLabelException;
 import com.google.gerrit.server.change.ChangeMessageResource;
 import com.google.gerrit.server.change.ChangeResource;
-import com.google.gerrit.server.change.SetPrivateOp;
 import com.google.gerrit.server.change.WorkInProgressOp;
 import com.google.gerrit.server.restapi.change.Abandon;
 import com.google.gerrit.server.restapi.change.ChangeIncludedIn;
@@ -96,6 +97,7 @@
 import com.google.gerrit.server.restapi.change.Rebase;
 import com.google.gerrit.server.restapi.change.Restore;
 import com.google.gerrit.server.restapi.change.Revert;
+import com.google.gerrit.server.restapi.change.RevertSubmission;
 import com.google.gerrit.server.restapi.change.Reviewers;
 import com.google.gerrit.server.restapi.change.Revisions;
 import com.google.gerrit.server.restapi.change.SetReadyForReview;
@@ -132,6 +134,7 @@
   private final ChangeResource change;
   private final Abandon abandon;
   private final Revert revert;
+  private final RevertSubmission revertSubmission;
   private final Restore restore;
   private final CreateMergePatchSet updateByMerge;
   private final Provider<SubmittedTogether> submittedTogether;
@@ -181,6 +184,7 @@
       ListReviewers listReviewers,
       Abandon abandon,
       Revert revert,
+      RevertSubmission revertSubmission,
       Restore restore,
       CreateMergePatchSet updateByMerge,
       Provider<SubmittedTogether> submittedTogether,
@@ -219,6 +223,7 @@
       @Assisted ChangeResource change) {
     this.changeApi = changeApi;
     this.revert = revert;
+    this.revertSubmission = revertSubmission;
     this.reviewers = reviewers;
     this.revisions = revisions;
     this.reviewerApi = reviewerApi;
@@ -319,7 +324,7 @@
   @Override
   public void setPrivate(boolean value, @Nullable String message) throws RestApiException {
     try {
-      SetPrivateOp.Input input = new SetPrivateOp.Input(message);
+      InputWithMessage input = new InputWithMessage(message);
       if (value) {
         postPrivate.apply(change, input);
       } else {
@@ -358,6 +363,15 @@
   }
 
   @Override
+  public RevertSubmissionInfo revertSubmission(RevertInput in) throws RestApiException {
+    try {
+      return revertSubmission.apply(change, in).value();
+    } catch (Exception e) {
+      throw asRestApiException("Cannot revert a change submission", e);
+    }
+  }
+
+  @Override
   public ChangeInfo createMergePatchSet(MergePatchSetInput in) throws RestApiException {
     try {
       return updateByMerge.apply(change, in).value();
diff --git a/java/com/google/gerrit/server/api/projects/LabelApiImpl.java b/java/com/google/gerrit/server/api/projects/LabelApiImpl.java
new file mode 100644
index 0000000..ad7ec31
--- /dev/null
+++ b/java/com/google/gerrit/server/api/projects/LabelApiImpl.java
@@ -0,0 +1,118 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.api.projects;
+
+import static com.google.gerrit.server.api.ApiUtil.asRestApiException;
+
+import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.api.projects.LabelApi;
+import com.google.gerrit.extensions.common.InputWithCommitMessage;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.IdString;
+import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectResource;
+import com.google.gerrit.server.restapi.project.CreateLabel;
+import com.google.gerrit.server.restapi.project.DeleteLabel;
+import com.google.gerrit.server.restapi.project.GetLabel;
+import com.google.gerrit.server.restapi.project.LabelsCollection;
+import com.google.gerrit.server.restapi.project.SetLabel;
+import com.google.inject.Inject;
+import com.google.inject.assistedinject.Assisted;
+
+public class LabelApiImpl implements LabelApi {
+  interface Factory {
+    LabelApiImpl create(ProjectResource project, String label);
+  }
+
+  private final LabelsCollection labels;
+  private final CreateLabel createLabel;
+  private final GetLabel getLabel;
+  private final SetLabel setLabel;
+  private final DeleteLabel deleteLabel;
+  private final ProjectCache projectCache;
+  private final String label;
+
+  private ProjectResource project;
+
+  @Inject
+  LabelApiImpl(
+      LabelsCollection labels,
+      CreateLabel createLabel,
+      GetLabel getLabel,
+      SetLabel setLabel,
+      DeleteLabel deleteLabel,
+      ProjectCache projectCache,
+      @Assisted ProjectResource project,
+      @Assisted String label) {
+    this.labels = labels;
+    this.createLabel = createLabel;
+    this.getLabel = getLabel;
+    this.setLabel = setLabel;
+    this.deleteLabel = deleteLabel;
+    this.projectCache = projectCache;
+    this.project = project;
+    this.label = label;
+  }
+
+  @Override
+  public LabelApi create(LabelDefinitionInput input) throws RestApiException {
+    try {
+      createLabel.apply(project, IdString.fromDecoded(label), input);
+
+      // recreate project resource because project state was updated by creating the new label and
+      // needs to be reloaded
+      project =
+          new ProjectResource(projectCache.checkedGet(project.getNameKey()), project.getUser());
+      return this;
+    } catch (Exception e) {
+      throw asRestApiException("Cannot create branch", e);
+    }
+  }
+
+  @Override
+  public LabelDefinitionInfo get() throws RestApiException {
+    try {
+      return getLabel.apply(resource()).value();
+    } catch (Exception e) {
+      throw asRestApiException("Cannot get label", e);
+    }
+  }
+
+  @Override
+  public LabelDefinitionInfo update(LabelDefinitionInput input) throws RestApiException {
+    try {
+      return setLabel.apply(resource(), input).value();
+    } catch (Exception e) {
+      throw asRestApiException("Cannot update label", e);
+    }
+  }
+
+  @Override
+  public void delete(@Nullable String commitMessage) throws RestApiException {
+    try {
+      deleteLabel.apply(resource(), new InputWithCommitMessage(commitMessage));
+    } catch (Exception e) {
+      throw asRestApiException("Cannot delete label", e);
+    }
+  }
+
+  private LabelResource resource() throws RestApiException, PermissionBackendException {
+    return labels.parse(project, IdString.fromDecoded(label));
+  }
+}
diff --git a/java/com/google/gerrit/server/api/projects/Module.java b/java/com/google/gerrit/server/api/projects/Module.java
index f1e21d28..8df5495 100644
--- a/java/com/google/gerrit/server/api/projects/Module.java
+++ b/java/com/google/gerrit/server/api/projects/Module.java
@@ -28,5 +28,6 @@
     factory(ChildProjectApiImpl.Factory.class);
     factory(CommitApiImpl.Factory.class);
     factory(DashboardApiImpl.Factory.class);
+    factory(LabelApiImpl.Factory.class);
   }
 }
diff --git a/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java b/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
index 1ac905d..6d7fc15 100644
--- a/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
+++ b/java/com/google/gerrit/server/api/projects/ProjectApiImpl.java
@@ -37,13 +37,16 @@
 import com.google.gerrit.extensions.api.projects.DescriptionInput;
 import com.google.gerrit.extensions.api.projects.HeadInput;
 import com.google.gerrit.extensions.api.projects.IndexProjectInput;
+import com.google.gerrit.extensions.api.projects.LabelApi;
 import com.google.gerrit.extensions.api.projects.ParentInput;
 import com.google.gerrit.extensions.api.projects.ProjectApi;
 import com.google.gerrit.extensions.api.projects.ProjectInput;
 import com.google.gerrit.extensions.api.projects.TagApi;
 import com.google.gerrit.extensions.api.projects.TagInfo;
+import com.google.gerrit.extensions.common.BatchLabelInput;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.Input;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
 import com.google.gerrit.extensions.common.ProjectInfo;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.IdString;
@@ -73,7 +76,9 @@
 import com.google.gerrit.server.restapi.project.IndexChanges;
 import com.google.gerrit.server.restapi.project.ListBranches;
 import com.google.gerrit.server.restapi.project.ListDashboards;
+import com.google.gerrit.server.restapi.project.ListLabels;
 import com.google.gerrit.server.restapi.project.ListTags;
+import com.google.gerrit.server.restapi.project.PostLabels;
 import com.google.gerrit.server.restapi.project.ProjectsCollection;
 import com.google.gerrit.server.restapi.project.PutConfig;
 import com.google.gerrit.server.restapi.project.PutDescription;
@@ -127,6 +132,9 @@
   private final SetParent setParent;
   private final Index index;
   private final IndexChanges indexChanges;
+  private final Provider<ListLabels> listLabels;
+  private final PostLabels postLabels;
+  private final LabelApiImpl.Factory labelApi;
 
   @AssistedInject
   ProjectApiImpl(
@@ -162,6 +170,9 @@
       SetParent setParent,
       Index index,
       IndexChanges indexChanges,
+      Provider<ListLabels> listLabels,
+      PostLabels postLabels,
+      LabelApiImpl.Factory labelApi,
       @Assisted ProjectResource project) {
     this(
         permissionBackend,
@@ -197,6 +208,9 @@
         setParent,
         index,
         indexChanges,
+        listLabels,
+        postLabels,
+        labelApi,
         null);
   }
 
@@ -234,6 +248,9 @@
       SetParent setParent,
       Index index,
       IndexChanges indexChanges,
+      Provider<ListLabels> listLabels,
+      PostLabels postLabels,
+      LabelApiImpl.Factory labelApi,
       @Assisted String name) {
     this(
         permissionBackend,
@@ -269,6 +286,9 @@
         setParent,
         index,
         indexChanges,
+        listLabels,
+        postLabels,
+        labelApi,
         name);
   }
 
@@ -306,6 +326,9 @@
       SetParent setParent,
       Index index,
       IndexChanges indexChanges,
+      Provider<ListLabels> listLabels,
+      PostLabels postLabels,
+      LabelApiImpl.Factory labelApi,
       String name) {
     this.permissionBackend = permissionBackend;
     this.createProject = createProject;
@@ -341,6 +364,9 @@
     this.name = name;
     this.index = index;
     this.indexChanges = indexChanges;
+    this.listLabels = listLabels;
+    this.postLabels = postLabels;
+    this.labelApi = labelApi;
   }
 
   @Override
@@ -672,4 +698,36 @@
     }
     return project;
   }
+
+  @Override
+  public ListLabelsRequest labels() {
+    return new ListLabelsRequest() {
+      @Override
+      public List<LabelDefinitionInfo> get() throws RestApiException {
+        try {
+          return listLabels.get().withInherited(inherited).apply(checkExists()).value();
+        } catch (Exception e) {
+          throw asRestApiException("Cannot list labels", e);
+        }
+      }
+    };
+  }
+
+  @Override
+  public LabelApi label(String labelName) throws RestApiException {
+    try {
+      return labelApi.create(checkExists(), labelName);
+    } catch (Exception e) {
+      throw asRestApiException("Cannot parse label", e);
+    }
+  }
+
+  @Override
+  public void labels(BatchLabelInput input) throws RestApiException {
+    try {
+      postLabels.apply(checkExists(), input);
+    } catch (Exception e) {
+      throw asRestApiException("Cannot update labels", e);
+    }
+  }
 }
diff --git a/java/com/google/gerrit/server/audit/BUILD b/java/com/google/gerrit/server/audit/BUILD
index 95929d3..a7ecde4 100644
--- a/java/com/google/gerrit/server/audit/BUILD
+++ b/java/com/google/gerrit/server/audit/BUILD
@@ -57,7 +57,6 @@
         "//lib/auto:auto-value-annotations",
         "//lib/bouncycastle:bcpkix-neverlink",
         "//lib/bouncycastle:bcprov-neverlink",
-        "//lib/commons:codec",
         "//lib/commons:compress",
         "//lib/commons:dbcp",
         "//lib/commons:lang",
diff --git a/java/com/google/gerrit/server/cache/CacheBackend.java b/java/com/google/gerrit/server/cache/CacheBackend.java
new file mode 100644
index 0000000..ec9876f
--- /dev/null
+++ b/java/com/google/gerrit/server/cache/CacheBackend.java
@@ -0,0 +1,25 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.cache;
+
+/** Caffeine is used as default cache backend, but can be overridden with Guava backend. */
+public enum CacheBackend {
+  CAFFEINE,
+  GUAVA;
+
+  public boolean isLegacyBackend() {
+    return this == GUAVA;
+  }
+}
diff --git a/java/com/google/gerrit/server/cache/CacheModule.java b/java/com/google/gerrit/server/cache/CacheModule.java
index 2878624..0fdc6f5 100644
--- a/java/com/google/gerrit/server/cache/CacheModule.java
+++ b/java/com/google/gerrit/server/cache/CacheModule.java
@@ -68,7 +68,8 @@
    */
   protected <K, V> CacheBinding<K, V> cache(
       String name, TypeLiteral<K> keyType, TypeLiteral<V> valType) {
-    CacheProvider<K, V> m = new CacheProvider<>(this, name, keyType, valType);
+    CacheProvider<K, V> m =
+        new CacheProvider<>(this, name, keyType, valType, CacheBackend.CAFFEINE);
     bindCache(m, name, keyType, valType);
     return m;
   }
@@ -123,7 +124,20 @@
    */
   protected <K, V> PersistentCacheBinding<K, V> persist(
       String name, Class<K> keyType, Class<V> valType) {
-    return persist(name, TypeLiteral.get(keyType), TypeLiteral.get(valType));
+    return persist(name, TypeLiteral.get(keyType), TypeLiteral.get(valType), CacheBackend.CAFFEINE);
+  }
+
+  /**
+   * Declare a named in-memory/on-disk cache.
+   *
+   * @param <K> type of key used to lookup entries.
+   * @param <V> type of value stored by the cache.
+   * @param backend cache backend.
+   * @return binding to describe the cache.
+   */
+  protected <K, V> PersistentCacheBinding<K, V> persist(
+      String name, Class<K> keyType, Class<V> valType, CacheBackend backend) {
+    return persist(name, TypeLiteral.get(keyType), TypeLiteral.get(valType), backend);
   }
 
   /**
@@ -135,7 +149,7 @@
    */
   protected <K, V> PersistentCacheBinding<K, V> persist(
       String name, Class<K> keyType, TypeLiteral<V> valType) {
-    return persist(name, TypeLiteral.get(keyType), valType);
+    return persist(name, TypeLiteral.get(keyType), valType, CacheBackend.CAFFEINE);
   }
 
   /**
@@ -146,8 +160,9 @@
    * @return binding to describe the cache.
    */
   protected <K, V> PersistentCacheBinding<K, V> persist(
-      String name, TypeLiteral<K> keyType, TypeLiteral<V> valType) {
-    PersistentCacheProvider<K, V> m = new PersistentCacheProvider<>(this, name, keyType, valType);
+      String name, TypeLiteral<K> keyType, TypeLiteral<V> valType, CacheBackend backend) {
+    PersistentCacheProvider<K, V> m =
+        new PersistentCacheProvider<>(this, name, keyType, valType, backend);
     bindCache(m, name, keyType, valType);
 
     Type cacheDefType =
diff --git a/java/com/google/gerrit/server/cache/CacheProvider.java b/java/com/google/gerrit/server/cache/CacheProvider.java
index b1a9b91..fe4244c 100644
--- a/java/com/google/gerrit/server/cache/CacheProvider.java
+++ b/java/com/google/gerrit/server/cache/CacheProvider.java
@@ -30,6 +30,7 @@
 
 class CacheProvider<K, V> implements Provider<Cache<K, V>>, CacheBinding<K, V>, CacheDef<K, V> {
   private final CacheModule module;
+  private final CacheBackend backend;
   final String name;
   private final TypeLiteral<K> keyType;
   private final TypeLiteral<V> valType;
@@ -44,11 +45,17 @@
   private MemoryCacheFactory memoryCacheFactory;
   private boolean frozen;
 
-  CacheProvider(CacheModule module, String name, TypeLiteral<K> keyType, TypeLiteral<V> valType) {
+  CacheProvider(
+      CacheModule module,
+      String name,
+      TypeLiteral<K> keyType,
+      TypeLiteral<V> valType,
+      CacheBackend backend) {
     this.module = module;
     this.name = name;
     this.keyType = keyType;
     this.valType = valType;
+    this.backend = backend;
   }
 
   @Inject(optional = true)
@@ -159,7 +166,9 @@
   public Cache<K, V> get() {
     freeze();
     CacheLoader<K, V> ldr = loader();
-    return ldr != null ? memoryCacheFactory.build(this, ldr) : memoryCacheFactory.build(this);
+    return ldr != null
+        ? memoryCacheFactory.build(this, ldr, backend)
+        : memoryCacheFactory.build(this, backend);
   }
 
   protected void checkNotFrozen() {
diff --git a/java/com/google/gerrit/server/cache/MemoryCacheFactory.java b/java/com/google/gerrit/server/cache/MemoryCacheFactory.java
index fc55753..558380d 100644
--- a/java/com/google/gerrit/server/cache/MemoryCacheFactory.java
+++ b/java/com/google/gerrit/server/cache/MemoryCacheFactory.java
@@ -19,7 +19,8 @@
 import com.google.common.cache.LoadingCache;
 
 public interface MemoryCacheFactory {
-  <K, V> Cache<K, V> build(CacheDef<K, V> def);
+  <K, V> Cache<K, V> build(CacheDef<K, V> def, CacheBackend backend);
 
-  <K, V> LoadingCache<K, V> build(CacheDef<K, V> def, CacheLoader<K, V> loader);
+  <K, V> LoadingCache<K, V> build(
+      CacheDef<K, V> def, CacheLoader<K, V> loader, CacheBackend backend);
 }
diff --git a/java/com/google/gerrit/server/cache/PersistentCacheFactory.java b/java/com/google/gerrit/server/cache/PersistentCacheFactory.java
index 27fa9ca..93f91ef 100644
--- a/java/com/google/gerrit/server/cache/PersistentCacheFactory.java
+++ b/java/com/google/gerrit/server/cache/PersistentCacheFactory.java
@@ -19,9 +19,10 @@
 import com.google.common.cache.LoadingCache;
 
 public interface PersistentCacheFactory {
-  <K, V> Cache<K, V> build(PersistentCacheDef<K, V> def);
+  <K, V> Cache<K, V> build(PersistentCacheDef<K, V> def, CacheBackend backend);
 
-  <K, V> LoadingCache<K, V> build(PersistentCacheDef<K, V> def, CacheLoader<K, V> loader);
+  <K, V> LoadingCache<K, V> build(
+      PersistentCacheDef<K, V> def, CacheLoader<K, V> loader, CacheBackend backend);
 
   void onStop(String plugin);
 }
diff --git a/java/com/google/gerrit/server/cache/PersistentCacheProvider.java b/java/com/google/gerrit/server/cache/PersistentCacheProvider.java
index 59d66e3..4fc107f 100644
--- a/java/com/google/gerrit/server/cache/PersistentCacheProvider.java
+++ b/java/com/google/gerrit/server/cache/PersistentCacheProvider.java
@@ -30,6 +30,7 @@
 
 class PersistentCacheProvider<K, V> extends CacheProvider<K, V>
     implements Provider<Cache<K, V>>, PersistentCacheBinding<K, V>, PersistentCacheDef<K, V> {
+  private final CacheBackend backend;
   private int version;
   private long diskLimit;
   private CacheSerializer<K> keySerializer;
@@ -39,9 +40,19 @@
 
   PersistentCacheProvider(
       CacheModule module, String name, TypeLiteral<K> keyType, TypeLiteral<V> valType) {
-    super(module, name, keyType, valType);
+    this(module, name, keyType, valType, CacheBackend.CAFFEINE);
+  }
+
+  PersistentCacheProvider(
+      CacheModule module,
+      String name,
+      TypeLiteral<K> keyType,
+      TypeLiteral<V> valType,
+      CacheBackend backend) {
+    super(module, name, keyType, valType, backend);
     version = -1;
     diskLimit = 128 << 20;
+    this.backend = backend;
   }
 
   @Inject(optional = true)
@@ -130,8 +141,8 @@
     freeze();
     CacheLoader<K, V> ldr = loader();
     return ldr != null
-        ? persistentCacheFactory.build(this, ldr)
-        : persistentCacheFactory.build(this);
+        ? persistentCacheFactory.build(this, ldr, backend)
+        : persistentCacheFactory.build(this, backend);
   }
 
   private static <T> void checkSerializer(
diff --git a/java/com/google/gerrit/server/cache/h2/H2CacheFactory.java b/java/com/google/gerrit/server/cache/h2/H2CacheFactory.java
index af1228d..2b068aa 100644
--- a/java/com/google/gerrit/server/cache/h2/H2CacheFactory.java
+++ b/java/com/google/gerrit/server/cache/h2/H2CacheFactory.java
@@ -21,6 +21,7 @@
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
 import com.google.gerrit.extensions.events.LifecycleListener;
 import com.google.gerrit.extensions.registration.DynamicMap;
+import com.google.gerrit.server.cache.CacheBackend;
 import com.google.gerrit.server.cache.MemoryCacheFactory;
 import com.google.gerrit.server.cache.PersistentCacheDef;
 import com.google.gerrit.server.cache.PersistentCacheFactory;
@@ -156,18 +157,21 @@
 
   @SuppressWarnings({"unchecked"})
   @Override
-  public <K, V> Cache<K, V> build(PersistentCacheDef<K, V> in) {
+  public <K, V> Cache<K, V> build(PersistentCacheDef<K, V> in, CacheBackend backend) {
     long limit = config.getLong("cache", in.configKey(), "diskLimit", in.diskLimit());
 
     if (cacheDir == null || limit <= 0) {
-      return memCacheFactory.build(in);
+      return memCacheFactory.build(in, backend);
     }
 
     H2CacheDefProxy<K, V> def = new H2CacheDefProxy<>(in);
     SqlStore<K, V> store = newSqlStore(def, limit);
     H2CacheImpl<K, V> cache =
         new H2CacheImpl<>(
-            executor, store, def.keyType(), (Cache<K, ValueHolder<V>>) memCacheFactory.build(def));
+            executor,
+            store,
+            def.keyType(),
+            (Cache<K, ValueHolder<V>>) memCacheFactory.build(def, backend));
     synchronized (caches) {
       caches.add(cache);
     }
@@ -176,11 +180,12 @@
 
   @SuppressWarnings("unchecked")
   @Override
-  public <K, V> LoadingCache<K, V> build(PersistentCacheDef<K, V> in, CacheLoader<K, V> loader) {
+  public <K, V> LoadingCache<K, V> build(
+      PersistentCacheDef<K, V> in, CacheLoader<K, V> loader, CacheBackend backend) {
     long limit = config.getLong("cache", in.configKey(), "diskLimit", in.diskLimit());
 
     if (cacheDir == null || limit <= 0) {
-      return memCacheFactory.build(in, loader);
+      return memCacheFactory.build(in, loader, backend);
     }
 
     H2CacheDefProxy<K, V> def = new H2CacheDefProxy<>(in);
@@ -188,7 +193,9 @@
     Cache<K, ValueHolder<V>> mem =
         (Cache<K, ValueHolder<V>>)
             memCacheFactory.build(
-                def, (CacheLoader<K, V>) new H2CacheImpl.Loader<>(executor, store, loader));
+                def,
+                (CacheLoader<K, V>) new H2CacheImpl.Loader<>(executor, store, loader),
+                backend);
     H2CacheImpl<K, V> cache = new H2CacheImpl<>(executor, store, def.keyType(), mem);
     synchronized (caches) {
       caches.add(cache);
diff --git a/java/com/google/gerrit/server/cache/mem/BUILD b/java/com/google/gerrit/server/cache/mem/BUILD
index d805e1f..a666df7 100644
--- a/java/com/google/gerrit/server/cache/mem/BUILD
+++ b/java/com/google/gerrit/server/cache/mem/BUILD
@@ -8,6 +8,8 @@
         "//java/com/google/gerrit/common:annotations",
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/server",
+        "//lib:caffeine",
+        "//lib:caffeine-guava",
         "//lib:guava",
         "//lib:jgit",
         "//lib/guice",
diff --git a/java/com/google/gerrit/server/cache/mem/DefaultMemoryCacheFactory.java b/java/com/google/gerrit/server/cache/mem/DefaultMemoryCacheFactory.java
index f76b8db..9906b3d 100644
--- a/java/com/google/gerrit/server/cache/mem/DefaultMemoryCacheFactory.java
+++ b/java/com/google/gerrit/server/cache/mem/DefaultMemoryCacheFactory.java
@@ -17,13 +17,18 @@
 import static java.util.concurrent.TimeUnit.NANOSECONDS;
 import static java.util.concurrent.TimeUnit.SECONDS;
 
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.github.benmanes.caffeine.cache.RemovalListener;
+import com.github.benmanes.caffeine.cache.Weigher;
+import com.github.benmanes.caffeine.guava.CaffeinatedGuava;
 import com.google.common.base.Strings;
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
 import com.google.common.cache.CacheLoader;
 import com.google.common.cache.LoadingCache;
-import com.google.common.cache.Weigher;
+import com.google.common.cache.RemovalNotification;
 import com.google.gerrit.common.Nullable;
+import com.google.gerrit.server.cache.CacheBackend;
 import com.google.gerrit.server.cache.CacheDef;
 import com.google.gerrit.server.cache.ForwardingRemovalListener;
 import com.google.gerrit.server.cache.MemoryCacheFactory;
@@ -46,25 +51,30 @@
   }
 
   @Override
-  public <K, V> Cache<K, V> build(CacheDef<K, V> def) {
-    return create(def).build();
+  public <K, V> Cache<K, V> build(CacheDef<K, V> def, CacheBackend backend) {
+    return backend.isLegacyBackend()
+        ? createLegacy(def).build()
+        : CaffeinatedGuava.build(create(def));
   }
 
   @Override
-  public <K, V> LoadingCache<K, V> build(CacheDef<K, V> def, CacheLoader<K, V> loader) {
-    return create(def).build(loader);
+  public <K, V> LoadingCache<K, V> build(
+      CacheDef<K, V> def, CacheLoader<K, V> loader, CacheBackend backend) {
+    return backend.isLegacyBackend()
+        ? createLegacy(def).build(loader)
+        : CaffeinatedGuava.build(create(def), loader);
   }
 
   @SuppressWarnings("unchecked")
-  private <K, V> CacheBuilder<K, V> create(CacheDef<K, V> def) {
-    CacheBuilder<K, V> builder = newCacheBuilder();
+  private <K, V> CacheBuilder<K, V> createLegacy(CacheDef<K, V> def) {
+    CacheBuilder<K, V> builder = newLegacyCacheBuilder();
     builder.recordStats();
     builder.maximumWeight(
         cfg.getLong("cache", def.configKey(), "memoryLimit", def.maximumWeight()));
 
     builder = builder.removalListener(forwardingRemovalListenerFactory.create(def.name()));
 
-    Weigher<K, V> weigher = def.weigher();
+    com.google.common.cache.Weigher<K, V> weigher = def.weigher();
     if (weigher == null) {
       weigher = unitWeight();
     }
@@ -98,6 +108,42 @@
     return builder;
   }
 
+  private <K, V> Caffeine<K, V> create(CacheDef<K, V> def) {
+    Caffeine<K, V> builder = newCacheBuilder();
+    builder.recordStats();
+    builder.maximumWeight(
+        cfg.getLong("cache", def.configKey(), "memoryLimit", def.maximumWeight()));
+    builder = builder.removalListener(newRemovalListener(def.name()));
+    builder.weigher(newWeigher(def.weigher()));
+
+    Duration expireAfterWrite = def.expireAfterWrite();
+    if (has(def.configKey(), "maxAge")) {
+      builder.expireAfterWrite(
+          ConfigUtil.getTimeUnit(
+              cfg, "cache", def.configKey(), "maxAge", toSeconds(expireAfterWrite), SECONDS),
+          SECONDS);
+    } else if (expireAfterWrite != null) {
+      builder.expireAfterWrite(expireAfterWrite.toNanos(), NANOSECONDS);
+    }
+
+    Duration expireAfterAccess = def.expireFromMemoryAfterAccess();
+    if (has(def.configKey(), "expireFromMemoryAfterAccess")) {
+      builder.expireAfterAccess(
+          ConfigUtil.getTimeUnit(
+              cfg,
+              "cache",
+              def.configKey(),
+              "expireFromMemoryAfterAccess",
+              toSeconds(expireAfterAccess),
+              SECONDS),
+          SECONDS);
+    } else if (expireAfterAccess != null) {
+      builder.expireAfterAccess(expireAfterAccess.toNanos(), NANOSECONDS);
+    }
+
+    return builder;
+  }
+
   private static long toSeconds(@Nullable Duration duration) {
     return duration != null ? duration.getSeconds() : 0;
   }
@@ -107,11 +153,31 @@
   }
 
   @SuppressWarnings("unchecked")
-  private static <K, V> CacheBuilder<K, V> newCacheBuilder() {
+  private static <K, V> CacheBuilder<K, V> newLegacyCacheBuilder() {
     return (CacheBuilder<K, V>) CacheBuilder.newBuilder();
   }
 
-  private static <K, V> Weigher<K, V> unitWeight() {
+  private static <K, V> com.google.common.cache.Weigher<K, V> unitWeight() {
     return (key, value) -> 1;
   }
+
+  @SuppressWarnings("unchecked")
+  private static <K, V> Caffeine<K, V> newCacheBuilder() {
+    return (Caffeine<K, V>) Caffeine.newBuilder();
+  }
+
+  @SuppressWarnings("unchecked")
+  private <V, K> RemovalListener<K, V> newRemovalListener(String cacheName) {
+    return (k, v, cause) ->
+        forwardingRemovalListenerFactory
+            .create(cacheName)
+            .onRemoval(
+                RemovalNotification.create(
+                    k, v, com.google.common.cache.RemovalCause.valueOf(cause.name())));
+  }
+
+  private static <K, V> Weigher<K, V> newWeigher(
+      com.google.common.cache.Weigher<K, V> guavaWeigher) {
+    return guavaWeigher == null ? Weigher.singletonWeigher() : (k, v) -> guavaWeigher.weigh(k, v);
+  }
 }
diff --git a/java/com/google/gerrit/server/change/ActionJson.java b/java/com/google/gerrit/server/change/ActionJson.java
index d493b31..031c1f2 100644
--- a/java/com/google/gerrit/server/change/ActionJson.java
+++ b/java/com/google/gerrit/server/change/ActionJson.java
@@ -136,6 +136,7 @@
     copy._number = changeInfo._number;
     copy.requirements = changeInfo.requirements;
     copy.revertOf = changeInfo.revertOf;
+    copy.submissionId = changeInfo.submissionId;
     copy.starred = changeInfo.starred;
     copy.stars = changeInfo.stars;
     copy.submitted = changeInfo.submitted;
diff --git a/java/com/google/gerrit/server/change/ChangeInserter.java b/java/com/google/gerrit/server/change/ChangeInserter.java
index 1bf5103..4263373 100644
--- a/java/com/google/gerrit/server/change/ChangeInserter.java
+++ b/java/com/google/gerrit/server/change/ChangeInserter.java
@@ -55,6 +55,7 @@
 import com.google.gerrit.server.git.GroupCollector;
 import com.google.gerrit.server.git.validators.CommitValidationException;
 import com.google.gerrit.server.git.validators.CommitValidators;
+import com.google.gerrit.server.logging.RequestId;
 import com.google.gerrit.server.mail.send.CreateChangeSender;
 import com.google.gerrit.server.notedb.ChangeUpdate;
 import com.google.gerrit.server.patch.PatchSetInfoFactory;
@@ -386,7 +387,7 @@
         psUtil.insert(
             ctx.getRevWalk(), update, psId, commitId, newGroups, pushCert, patchSetDescription);
 
-    /* TODO: fixStatus is used here because the tests
+    /* TODO: fixStatusToMerged is used here because the tests
      * (byStatusClosed() in AbstractQueryChangesTest)
      * insert changes that are already merged,
      * and setStatus may not be used to set the Status to merged
@@ -394,7 +395,11 @@
      * is it possible to make the tests use the merge code path,
      * instead of setting the status directly?
      */
-    update.fixStatus(change.getStatus());
+    if (change.getStatus() == Change.Status.MERGED) {
+      update.fixStatusToMerged(new RequestId(ctx.getChange().getId().toString()));
+    } else {
+      update.setStatus(change.getStatus());
+    }
 
     reviewerAdditions =
         reviewerAdder.prepare(ctx.getNotes(), ctx.getUser(), getReviewerInputs(), true);
diff --git a/java/com/google/gerrit/server/change/ChangeJson.java b/java/com/google/gerrit/server/change/ChangeJson.java
index 3b7a2c4..21ee28a 100644
--- a/java/com/google/gerrit/server/change/ChangeJson.java
+++ b/java/com/google/gerrit/server/change/ChangeJson.java
@@ -138,6 +138,7 @@
           COMMIT_FOOTERS,
           CURRENT_ACTIONS,
           CURRENT_COMMIT,
+          DETAILED_LABELS, // may need to load ChangeNotes to check remove reviewer permissions
           MESSAGES);
 
   @Singleton
@@ -586,6 +587,7 @@
       out.plugins = pluginDefinedAttributesFactory.get().create(cd);
     }
     out.revertOf = cd.change().getRevertOf() != null ? cd.change().getRevertOf().get() : null;
+    out.submissionId = cd.change().getSubmissionId();
 
     if (has(REVIEWER_UPDATES)) {
       out.reviewerUpdates = reviewerUpdates(cd);
diff --git a/java/com/google/gerrit/server/change/ConsistencyChecker.java b/java/com/google/gerrit/server/change/ConsistencyChecker.java
index 0374a1c..19db5ee 100644
--- a/java/com/google/gerrit/server/change/ConsistencyChecker.java
+++ b/java/com/google/gerrit/server/change/ConsistencyChecker.java
@@ -44,6 +44,7 @@
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.account.Accounts;
 import com.google.gerrit.server.git.GitRepositoryManager;
+import com.google.gerrit.server.logging.RequestId;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.notedb.PatchSetState;
 import com.google.gerrit.server.patch.PatchSetInfoFactory;
@@ -576,7 +577,8 @@
     @Override
     public boolean updateChange(ChangeContext ctx) {
       ctx.getChange().setStatus(Change.Status.MERGED);
-      ctx.getUpdate(ctx.getChange().currentPatchSetId()).fixStatus(Change.Status.MERGED);
+      ctx.getUpdate(ctx.getChange().currentPatchSetId())
+          .fixStatusToMerged(new RequestId(ctx.getChange().getId().toString()));
       p.status = Status.FIXED;
       p.outcome = "Marked change as merged";
       return true;
diff --git a/java/com/google/gerrit/server/change/FileContentUtil.java b/java/com/google/gerrit/server/change/FileContentUtil.java
index 5c7946c..49c1fe2 100644
--- a/java/com/google/gerrit/server/change/FileContentUtil.java
+++ b/java/com/google/gerrit/server/change/FileContentUtil.java
@@ -100,7 +100,7 @@
 
   public BinaryResult getContent(
       Repository repo, ProjectState project, ObjectId revstr, String path)
-      throws IOException, ResourceNotFoundException {
+      throws IOException, ResourceNotFoundException, BadRequestException {
     try (RevWalk rw = new RevWalk(repo)) {
       RevCommit commit = rw.parseCommit(revstr);
       try (TreeWalk tw = TreeWalk.forPath(rw.getObjectReader(), path, commit.getTree())) {
@@ -114,6 +114,10 @@
           return BinaryResult.create(id.name()).setContentType(X_GIT_GITLINK).base64();
         }
 
+        if (mode == org.eclipse.jgit.lib.FileMode.TREE) {
+          throw new BadRequestException("cannot retrieve content of directories");
+        }
+
         ObjectLoader obj = repo.open(id, OBJ_BLOB);
         byte[] raw;
         try {
diff --git a/java/com/google/gerrit/server/change/SetPrivateOp.java b/java/com/google/gerrit/server/change/SetPrivateOp.java
index 28d178d..382a4f6 100644
--- a/java/com/google/gerrit/server/change/SetPrivateOp.java
+++ b/java/com/google/gerrit/server/change/SetPrivateOp.java
@@ -19,6 +19,7 @@
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.ChangeMessage;
 import com.google.gerrit.entities.PatchSet;
+import com.google.gerrit.extensions.common.InputWithMessage;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.server.ChangeMessagesUtil;
@@ -34,25 +35,15 @@
 import com.google.inject.assistedinject.Assisted;
 
 public class SetPrivateOp implements BatchUpdateOp {
-  public static class Input {
-    String message;
-
-    public Input() {}
-
-    public Input(String message) {
-      this.message = message;
-    }
-  }
-
   public interface Factory {
-    SetPrivateOp create(boolean isPrivate, @Nullable Input input);
+    SetPrivateOp create(boolean isPrivate, @Nullable InputWithMessage input);
   }
 
   private final PrivateStateChanged privateStateChanged;
   private final PatchSetUtil psUtil;
   private final ChangeMessagesUtil cmUtil;
   private final boolean isPrivate;
-  @Nullable private final Input input;
+  @Nullable private final InputWithMessage input;
 
   private Change change;
   private PatchSet ps;
@@ -64,7 +55,7 @@
       PatchSetUtil psUtil,
       ChangeMessagesUtil cmUtil,
       @Assisted boolean isPrivate,
-      @Assisted @Nullable Input input) {
+      @Assisted @Nullable InputWithMessage input) {
     this.privateStateChanged = privateStateChanged;
     this.psUtil = psUtil;
     this.cmUtil = cmUtil;
diff --git a/java/com/google/gerrit/server/change/WorkInProgressOp.java b/java/com/google/gerrit/server/change/WorkInProgressOp.java
index 78edadab..283cff8 100644
--- a/java/com/google/gerrit/server/change/WorkInProgressOp.java
+++ b/java/com/google/gerrit/server/change/WorkInProgressOp.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.entities.ChangeMessage;
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.extensions.api.changes.NotifyHandling;
+import com.google.gerrit.extensions.common.InputWithMessage;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.extensions.events.WorkInProgressStateChanged;
@@ -34,15 +35,15 @@
 
 /* Set work in progress or ready for review state on a change */
 public class WorkInProgressOp implements BatchUpdateOp {
-  public static class Input {
-    @Nullable public String message;
-
+  public static class Input extends InputWithMessage {
     @Nullable public NotifyHandling notify;
 
-    public Input() {}
+    public Input() {
+      this(null);
+    }
 
-    public Input(String message) {
-      this.message = message;
+    public Input(@Nullable String message) {
+      super(message);
     }
   }
 
diff --git a/java/com/google/gerrit/server/config/GerritGlobalModule.java b/java/com/google/gerrit/server/config/GerritGlobalModule.java
index 3b9c40e..2a0466f 100644
--- a/java/com/google/gerrit/server/config/GerritGlobalModule.java
+++ b/java/com/google/gerrit/server/config/GerritGlobalModule.java
@@ -79,6 +79,7 @@
 import com.google.gerrit.server.CreateGroupPermissionSyncer;
 import com.google.gerrit.server.DynamicOptions;
 import com.google.gerrit.server.ExceptionHook;
+import com.google.gerrit.server.ExceptionHookImpl;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.RequestListener;
 import com.google.gerrit.server.TraceRequestListener;
@@ -393,6 +394,7 @@
     DynamicSet.bind(binder(), RequestListener.class).to(TraceRequestListener.class);
     DynamicSet.setOf(binder(), ChangeETagComputation.class);
     DynamicSet.setOf(binder(), ExceptionHook.class);
+    DynamicSet.bind(binder(), ExceptionHook.class).to(ExceptionHookImpl.class);
     DynamicSet.setOf(binder(), MailSoyTemplateProvider.class);
 
     DynamicMap.mapOf(binder(), MailFilter.class);
diff --git a/java/com/google/gerrit/server/config/OperatorAliasConfig.java b/java/com/google/gerrit/server/config/OperatorAliasConfig.java
new file mode 100644
index 0000000..0c5fc6e
--- /dev/null
+++ b/java/com/google/gerrit/server/config/OperatorAliasConfig.java
@@ -0,0 +1,46 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.config;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import java.util.HashMap;
+import java.util.Map;
+import org.eclipse.jgit.lib.Config;
+
+@Singleton
+public class OperatorAliasConfig {
+  private static final String SECTION = "operator-alias";
+  private static final String SUBSECTION_CHANGE = "change";
+  private final Config cfg;
+  private final Map<String, String> changeQueryOperatorAliases;
+
+  @Inject
+  OperatorAliasConfig(@GerritServerConfig Config cfg) {
+    this.cfg = cfg;
+    changeQueryOperatorAliases = new HashMap<>();
+    loadChangeOperatorAliases();
+  }
+
+  public Map<String, String> getChangeQueryOperatorAliases() {
+    return changeQueryOperatorAliases;
+  }
+
+  private void loadChangeOperatorAliases() {
+    for (String name : cfg.getNames(SECTION, SUBSECTION_CHANGE)) {
+      changeQueryOperatorAliases.put(name, cfg.getString(SECTION, SUBSECTION_CHANGE, name));
+    }
+  }
+}
diff --git a/java/com/google/gerrit/server/edit/ChangeEditModifier.java b/java/com/google/gerrit/server/edit/ChangeEditModifier.java
index afaf695..c05a47d 100644
--- a/java/com/google/gerrit/server/edit/ChangeEditModifier.java
+++ b/java/com/google/gerrit/server/edit/ChangeEditModifier.java
@@ -17,12 +17,14 @@
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.PatchSet;
+import com.google.gerrit.entities.Project;
 import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.MergeConflictException;
 import com.google.gerrit.extensions.restapi.RawInput;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.GerritPersonIdent;
@@ -228,7 +230,12 @@
         createCommit(repository, basePatchSetCommit, baseTree, newCommitMessage, nowTimestamp);
 
     if (optionalChangeEdit.isPresent()) {
-      updateEdit(repository, optionalChangeEdit.get(), newEditCommit, nowTimestamp);
+      updateEdit(
+          notes.getProjectName(),
+          repository,
+          optionalChangeEdit.get(),
+          newEditCommit,
+          nowTimestamp);
     } else {
       createEdit(repository, notes, basePatchSet, newEditCommit, nowTimestamp);
     }
@@ -331,7 +338,12 @@
         createCommit(repository, basePatchSetCommit, newTreeId, commitMessage, nowTimestamp);
 
     if (optionalChangeEdit.isPresent()) {
-      updateEdit(repository, optionalChangeEdit.get(), newEditCommit, nowTimestamp);
+      updateEdit(
+          notes.getProjectName(),
+          repository,
+          optionalChangeEdit.get(),
+          newEditCommit,
+          nowTimestamp);
     } else {
       createEdit(repository, notes, basePatchSet, newEditCommit, nowTimestamp);
     }
@@ -384,7 +396,12 @@
         createCommit(repository, patchSetCommit, newTreeId, commitMessage, nowTimestamp);
 
     if (optionalChangeEdit.isPresent()) {
-      return updateEdit(repository, optionalChangeEdit.get(), newEditCommit, nowTimestamp);
+      return updateEdit(
+          notes.getProjectName(),
+          repository,
+          optionalChangeEdit.get(),
+          newEditCommit,
+          nowTimestamp);
     }
     return createEdit(repository, notes, patchSet, newEditCommit, nowTimestamp);
   }
@@ -531,7 +548,13 @@
       throws IOException {
     Change change = notes.getChange();
     String editRefName = getEditRefName(change, basePatchSet);
-    updateReference(repository, editRefName, ObjectId.zeroId(), newEditCommitId, timestamp);
+    updateReference(
+        notes.getProjectName(),
+        repository,
+        editRefName,
+        ObjectId.zeroId(),
+        newEditCommitId,
+        timestamp);
     reindex(change);
 
     RevCommit newEditCommit = lookupCommit(repository, newEditCommitId);
@@ -544,11 +567,16 @@
   }
 
   private ChangeEdit updateEdit(
-      Repository repository, ChangeEdit changeEdit, ObjectId newEditCommitId, Timestamp timestamp)
+      Project.NameKey projectName,
+      Repository repository,
+      ChangeEdit changeEdit,
+      ObjectId newEditCommitId,
+      Timestamp timestamp)
       throws IOException {
     String editRefName = changeEdit.getRefName();
     RevCommit currentEditCommit = changeEdit.getEditCommit();
-    updateReference(repository, editRefName, currentEditCommit, newEditCommitId, timestamp);
+    updateReference(
+        projectName, repository, editRefName, currentEditCommit, newEditCommitId, timestamp);
     reindex(changeEdit.getChange());
 
     RevCommit newEditCommit = lookupCommit(repository, newEditCommitId);
@@ -557,6 +585,7 @@
   }
 
   private void updateReference(
+      Project.NameKey projectName,
       Repository repository,
       String refName,
       ObjectId currentObjectId,
@@ -571,14 +600,12 @@
     ru.setForceUpdate(true);
     try (RevWalk revWalk = new RevWalk(repository)) {
       RefUpdate.Result res = ru.update(revWalk);
+      String message = "cannot update " + ru.getName() + " in " + projectName + ": " + res;
+      if (res == RefUpdate.Result.LOCK_FAILURE) {
+        throw new LockFailureException(message, ru);
+      }
       if (res != RefUpdate.Result.NEW && res != RefUpdate.Result.FORCED) {
-        throw new IOException(
-            "cannot update "
-                + ru.getName()
-                + " in "
-                + repository.getDirectory()
-                + ": "
-                + ru.getResult());
+        throw new IOException(message);
       }
     }
   }
diff --git a/java/com/google/gerrit/server/edit/ChangeEditUtil.java b/java/com/google/gerrit/server/edit/ChangeEditUtil.java
index 6ba30bf..926e0d5 100644
--- a/java/com/google/gerrit/server/edit/ChangeEditUtil.java
+++ b/java/com/google/gerrit/server/edit/ChangeEditUtil.java
@@ -24,6 +24,7 @@
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.IdentifiedUser;
@@ -248,9 +249,10 @@
       case NEW:
       case NO_CHANGE:
         break;
+      case LOCK_FAILURE:
+        throw new LockFailureException(String.format("Failed to delete ref %s", refName), ru);
       case FAST_FORWARD:
       case IO_FAILURE:
-      case LOCK_FAILURE:
       case NOT_ATTEMPTED:
       case REJECTED:
       case REJECTED_CURRENT_BRANCH:
diff --git a/java/com/google/gerrit/server/fixes/FixReplacementInterpreter.java b/java/com/google/gerrit/server/fixes/FixReplacementInterpreter.java
index a1682fe..9d6df7d 100644
--- a/java/com/google/gerrit/server/fixes/FixReplacementInterpreter.java
+++ b/java/com/google/gerrit/server/fixes/FixReplacementInterpreter.java
@@ -20,6 +20,7 @@
 import com.google.gerrit.common.RawInputUtil;
 import com.google.gerrit.entities.Comment;
 import com.google.gerrit.entities.FixReplacement;
+import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.BinaryResult;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
@@ -69,7 +70,8 @@
       ProjectState projectState,
       ObjectId patchSetCommitId,
       List<FixReplacement> fixReplacements)
-      throws ResourceNotFoundException, IOException, ResourceConflictException {
+      throws BadRequestException, ResourceNotFoundException, IOException,
+          ResourceConflictException {
     requireNonNull(fixReplacements, "Fix replacements must not be null");
 
     Map<String, List<FixReplacement>> fixReplacementsPerFilePath =
@@ -91,7 +93,8 @@
       ObjectId patchSetCommitId,
       String filePath,
       List<FixReplacement> fixReplacements)
-      throws ResourceNotFoundException, IOException, ResourceConflictException {
+      throws BadRequestException, ResourceNotFoundException, IOException,
+          ResourceConflictException {
     String fileContent = getFileContent(repository, projectState, patchSetCommitId, filePath);
     String newFileContent = getNewFileContent(fileContent, fixReplacements);
     return new ChangeFileContentModification(filePath, RawInputUtil.create(newFileContent));
@@ -99,7 +102,7 @@
 
   private String getFileContent(
       Repository repository, ProjectState projectState, ObjectId patchSetCommitId, String filePath)
-      throws ResourceNotFoundException, IOException {
+      throws ResourceNotFoundException, BadRequestException, IOException {
     try (BinaryResult fileContent =
         fileContentUtil.getContent(repository, projectState, patchSetCommitId, filePath)) {
       return fileContent.asString();
diff --git a/java/com/google/gerrit/server/git/DelegateRefDatabase.java b/java/com/google/gerrit/server/git/DelegateRefDatabase.java
index 34dd6a9..decae05 100644
--- a/java/com/google/gerrit/server/git/DelegateRefDatabase.java
+++ b/java/com/google/gerrit/server/git/DelegateRefDatabase.java
@@ -17,6 +17,9 @@
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import org.eclipse.jgit.annotations.NonNull;
+import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.RefDatabase;
 import org.eclipse.jgit.lib.RefRename;
@@ -24,7 +27,8 @@
 import org.eclipse.jgit.lib.Repository;
 
 /**
- * Wrapper around {@link RefDatabase} that delegates all calls to the wrapped {@link RefDatabase}.
+ * Wrapper around {@link RefDatabase} that delegates all calls to the wrapped {@link Repository}'s
+ * {@link RefDatabase}.
  */
 public class DelegateRefDatabase extends RefDatabase {
 
@@ -41,7 +45,7 @@
 
   @Override
   public void close() {
-    delegate.close();
+    delegate.getRefDatabase().close();
   }
 
   @Override
@@ -71,6 +75,12 @@
   }
 
   @Override
+  @NonNull
+  public Set<Ref> getTipsWithSha1(ObjectId id) throws IOException {
+    return delegate.getRefDatabase().getTipsWithSha1(id);
+  }
+
+  @Override
   public List<Ref> getAdditionalRefs() throws IOException {
     return delegate.getRefDatabase().getAdditionalRefs();
   }
diff --git a/java/com/google/gerrit/server/git/DelegateRepository.java b/java/com/google/gerrit/server/git/DelegateRepository.java
index 800490d..b61488b 100644
--- a/java/com/google/gerrit/server/git/DelegateRepository.java
+++ b/java/com/google/gerrit/server/git/DelegateRepository.java
@@ -81,7 +81,8 @@
   @SuppressWarnings("rawtypes")
   private static BaseRepositoryBuilder toBuilder(Repository repo) {
     if (!repo.isBare()) {
-      throw new IllegalArgumentException("non-bare repository is not supported");
+      throw new IllegalArgumentException(
+          "non-bare repository is not supported: " + repo.getIdentifier());
     }
 
     return new BaseRepositoryBuilder<>().setFS(repo.getFS()).setGitDir(repo.getDirectory());
diff --git a/java/com/google/gerrit/server/git/GroupCollector.java b/java/com/google/gerrit/server/git/GroupCollector.java
index c284f7f4..1f0dcd4 100644
--- a/java/com/google/gerrit/server/git/GroupCollector.java
+++ b/java/com/google/gerrit/server/git/GroupCollector.java
@@ -23,16 +23,18 @@
 import com.google.common.collect.Iterables;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.MultimapBuilder;
-import com.google.common.collect.Multimaps;
 import com.google.common.collect.SetMultimap;
 import com.google.common.collect.Sets;
 import com.google.common.collect.SortedSetMultimap;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.entities.Project;
+import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.change.RevisionResource;
+import com.google.gerrit.server.git.receive.ReceivePackRefCache;
 import com.google.gerrit.server.notedb.ChangeNotes;
+import java.io.IOException;
 import java.util.ArrayDeque;
 import java.util.Collection;
 import java.util.Deque;
@@ -87,24 +89,29 @@
     return rsrc.getPatchSet().groups();
   }
 
-  private interface Lookup {
+  interface Lookup {
     List<String> lookup(PatchSet.Id psId);
   }
 
-  private final ListMultimap<ObjectId, PatchSet.Id> patchSetsBySha;
+  private final ReceivePackRefCache receivePackRefCache;
   private final ListMultimap<ObjectId, String> groups;
   private final SetMultimap<String, String> groupAliases;
   private final Lookup groupLookup;
 
   private boolean done;
 
+  /**
+   * Returns a new {@link GroupCollector} instance.
+   *
+   * @see GroupCollector for what this class does.
+   */
   public static GroupCollector create(
-      ListMultimap<ObjectId, Ref> changeRefsById,
+      ReceivePackRefCache receivePackRefCache,
       PatchSetUtil psUtil,
       ChangeNotes.Factory notesFactory,
       Project.NameKey project) {
     return new GroupCollector(
-        transformRefs(changeRefsById),
+        receivePackRefCache,
         psId -> {
           // TODO(dborowitz): Reuse open repository from caller.
           ChangeNotes notes = notesFactory.createChecked(project, psId.changeId());
@@ -113,31 +120,32 @@
         });
   }
 
-  private GroupCollector(ListMultimap<ObjectId, PatchSet.Id> patchSetsBySha, Lookup groupLookup) {
-    this.patchSetsBySha = patchSetsBySha;
+  /**
+   * Returns a new {@link GroupCollector} instance.
+   *
+   * <p>Used in production code by using {@link com.google.gerrit.server.notedb.ChangeNotes.Factory}
+   * to get a group SHA1 (40 bytes string representation) from a {@link
+   * com.google.gerrit.entities.PatchSet.Id}. Unit tests use this method directly by passing their
+   * own lookup function.
+   *
+   * @see GroupCollector for what this class does.
+   */
+  @VisibleForTesting
+  GroupCollector(ReceivePackRefCache receivePackRefCache, Lookup groupLookup) {
+    this.receivePackRefCache = receivePackRefCache;
     this.groupLookup = groupLookup;
     groups = MultimapBuilder.hashKeys().arrayListValues().build();
     groupAliases = MultimapBuilder.hashKeys().hashSetValues().build();
   }
 
-  private static ListMultimap<ObjectId, PatchSet.Id> transformRefs(
-      ListMultimap<ObjectId, Ref> refs) {
-    return Multimaps.transformValues(refs, r -> PatchSet.Id.fromRef(r.getName()));
-  }
-
-  @VisibleForTesting
-  GroupCollector(
-      ListMultimap<ObjectId, PatchSet.Id> patchSetsBySha,
-      ListMultimap<PatchSet.Id, String> groupLookup) {
-    this(
-        patchSetsBySha,
-        psId -> {
-          List<String> groups = groupLookup.get(psId);
-          return !groups.isEmpty() ? groups : null;
-        });
-  }
-
-  public void visit(RevCommit c) {
+  /**
+   * Process the given {@link RevCommit}. Callers must call {@link #visit(RevCommit)} on all commits
+   * between the current branch tip and the tip of a push, in reverse topo order (parents before
+   * children). Once all commits have been visited, call {@link #getGroups()} for the result.
+   *
+   * @see GroupCollector for what this class does.
+   */
+  public void visit(RevCommit c) throws IOException {
     checkState(!done, "visit() called after getGroups()");
     Set<RevCommit> interestingParents = getInterestingParents(c);
 
@@ -197,7 +205,10 @@
     }
   }
 
-  public SortedSetMultimap<ObjectId, String> getGroups() {
+  /**
+   * Returns the groups that got collected from visiting commits using {@link #visit(RevCommit)}.
+   */
+  public SortedSetMultimap<ObjectId, String> getGroups() throws IOException {
     done = true;
     SortedSetMultimap<ObjectId, String> result =
         MultimapBuilder.hashKeys(groups.keySet().size()).treeSetValues().build();
@@ -218,12 +229,13 @@
     return result;
   }
 
-  private boolean isGroupFromExistingPatchSet(RevCommit commit, String group) {
+  private boolean isGroupFromExistingPatchSet(RevCommit commit, String group) throws IOException {
     ObjectId id = parseGroup(commit, group);
-    return id != null && patchSetsBySha.containsKey(id);
+    return id != null && !receivePackRefCache.tipsFromObjectId(id, RefNames.REFS_CHANGES).isEmpty();
   }
 
-  private Set<String> resolveGroups(ObjectId forCommit, Collection<String> candidates) {
+  private Set<String> resolveGroups(ObjectId forCommit, Collection<String> candidates)
+      throws IOException {
     Set<String> actual = Sets.newTreeSet();
     Set<String> done = Sets.newHashSetWithExpectedSize(candidates.size());
     Set<String> seen = Sets.newHashSetWithExpectedSize(candidates.size());
@@ -258,16 +270,20 @@
     }
   }
 
-  private Iterable<String> resolveGroup(ObjectId forCommit, String group) {
+  private Iterable<String> resolveGroup(ObjectId forCommit, String group) throws IOException {
     ObjectId id = parseGroup(forCommit, group);
     if (id != null) {
-      PatchSet.Id psId = Iterables.getFirst(patchSetsBySha.get(id), null);
-      if (psId != null) {
-        List<String> groups = groupLookup.lookup(psId);
-        // Group for existing patch set may be missing, e.g. if group has not
-        // been migrated yet.
-        if (groups != null && !groups.isEmpty()) {
-          return groups;
+      Ref ref =
+          Iterables.getFirst(receivePackRefCache.tipsFromObjectId(id, RefNames.REFS_CHANGES), null);
+      if (ref != null) {
+        PatchSet.Id psId = PatchSet.Id.fromRef(ref.getName());
+        if (psId != null) {
+          List<String> groups = groupLookup.lookup(psId);
+          // Group for existing patch set may be missing, e.g. if group has not
+          // been migrated yet.
+          if (groups != null && !groups.isEmpty()) {
+            return groups;
+          }
         }
       }
     }
diff --git a/java/com/google/gerrit/server/git/MergedByPushOp.java b/java/com/google/gerrit/server/git/MergedByPushOp.java
index 858a55a..9aebebf 100644
--- a/java/com/google/gerrit/server/git/MergedByPushOp.java
+++ b/java/com/google/gerrit/server/git/MergedByPushOp.java
@@ -26,6 +26,7 @@
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.config.SendEmailExecutor;
 import com.google.gerrit.server.extensions.events.ChangeMerged;
+import com.google.gerrit.server.logging.RequestId;
 import com.google.gerrit.server.mail.send.MergedSender;
 import com.google.gerrit.server.notedb.ChangeUpdate;
 import com.google.gerrit.server.patch.PatchSetInfoFactory;
@@ -51,6 +52,7 @@
     MergedByPushOp create(
         RequestScopePropagator requestScopePropagator,
         PatchSet.Id psId,
+        @Assisted RequestId submissionId,
         @Assisted("refName") String refName,
         @Assisted("mergeResultRevId") String mergeResultRevId);
   }
@@ -64,6 +66,7 @@
   private final ChangeMerged changeMerged;
 
   private final PatchSet.Id psId;
+  private final RequestId submissionId;
   private final String refName;
   private final String mergeResultRevId;
 
@@ -83,6 +86,7 @@
       ChangeMerged changeMerged,
       @Assisted RequestScopePropagator requestScopePropagator,
       @Assisted PatchSet.Id psId,
+      @Assisted RequestId submissionId,
       @Assisted("refName") String refName,
       @Assisted("mergeResultRevId") String mergeResultRevId) {
     this.patchSetInfoFactory = patchSetInfoFactory;
@@ -92,6 +96,7 @@
     this.sendEmailExecutor = sendEmailExecutor;
     this.changeMerged = changeMerged;
     this.requestScopePropagator = requestScopePropagator;
+    this.submissionId = submissionId;
     this.psId = psId;
     this.refName = refName;
     this.mergeResultRevId = mergeResultRevId;
@@ -132,9 +137,10 @@
     }
     change.setCurrentPatchSet(info);
     change.setStatus(Change.Status.MERGED);
+    change.setSubmissionId(submissionId.toStringForStorage());
     // we cannot reconstruct the submit records for when this change was
-    // submitted, this is why we must fix the status
-    update.fixStatus(Change.Status.MERGED);
+    // submitted, this is why we must fix the status and other details.
+    update.fixStatusToMerged(submissionId);
     update.setCurrentPatchSet();
     if (change.isWorkInProgress()) {
       change.setWorkInProgress(false);
diff --git a/java/com/google/gerrit/server/git/PermissionAwareReadOnlyRefDatabase.java b/java/com/google/gerrit/server/git/PermissionAwareReadOnlyRefDatabase.java
index 8f7e684..8421e54 100644
--- a/java/com/google/gerrit/server/git/PermissionAwareReadOnlyRefDatabase.java
+++ b/java/com/google/gerrit/server/git/PermissionAwareReadOnlyRefDatabase.java
@@ -26,10 +26,13 @@
 import java.io.IOException;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import org.eclipse.jgit.annotations.NonNull;
 import org.eclipse.jgit.annotations.Nullable;
+import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.RefRename;
 import org.eclipse.jgit.lib.RefUpdate;
@@ -156,4 +159,17 @@
     }
     return null;
   }
+
+  @Override
+  @NonNull
+  public Set<Ref> getTipsWithSha1(ObjectId id) throws IOException {
+    Set<Ref> unfiltered = super.getTipsWithSha1(id);
+    Set<Ref> result = new HashSet<>(unfiltered.size());
+    for (Ref ref : unfiltered) {
+      if (exactRef(ref.getName()) != null) {
+        result.add(ref);
+      }
+    }
+    return result;
+  }
 }
diff --git a/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java b/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
index 7038736..7767fe2 100644
--- a/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
+++ b/java/com/google/gerrit/server/git/receive/AsyncReceiveCommits.java
@@ -310,7 +310,8 @@
 
     allRefsWatcher = new AllRefsWatcher();
     receivePack.setAdvertiseRefsHook(
-        ReceiveCommitsAdvertiseRefsHookChain.create(allRefsWatcher, queryProvider, projectName));
+        ReceiveCommitsAdvertiseRefsHookChain.create(
+            allRefsWatcher, queryProvider, projectName, user.getAccountId()));
     resultChangeIds = new ResultChangeIds();
     receiveCommits =
         factory.create(
diff --git a/java/com/google/gerrit/server/git/receive/BUILD b/java/com/google/gerrit/server/git/receive/BUILD
index d89bb63..7402a37 100644
--- a/java/com/google/gerrit/server/git/receive/BUILD
+++ b/java/com/google/gerrit/server/git/receive/BUILD
@@ -2,15 +2,20 @@
 
 java_library(
     name = "receive",
-    srcs = glob(["**/*.java"]),
+    srcs = glob(
+        ["**/*.java"],
+        exclude = ["ReceivePackRefCache.java"],
+    ),
     visibility = ["//visibility:public"],
     deps = [
+        ":ref_cache",
         "//java/com/google/gerrit/common:annotations",
         "//java/com/google/gerrit/common:server",
         "//java/com/google/gerrit/entities",
         "//java/com/google/gerrit/exceptions",
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/git",
+        "//java/com/google/gerrit/index",
         "//java/com/google/gerrit/metrics",
         "//java/com/google/gerrit/server",
         "//java/com/google/gerrit/server/logging",
@@ -26,3 +31,14 @@
         "//lib/guice:guice-assistedinject",
     ],
 )
+
+java_library(
+    name = "ref_cache",
+    srcs = glob(["ReceivePackRefCache.java"]),
+    visibility = ["//visibility:public"],
+    deps = [
+        "//java/com/google/gerrit/entities",
+        "//lib:guava",
+        "//lib:jgit",
+    ],
+)
diff --git a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
index c6c9b39..cec9e4e 100644
--- a/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
+++ b/java/com/google/gerrit/server/git/receive/ReceiveCommits.java
@@ -343,7 +343,6 @@
   private final SetPrivateOp.Factory setPrivateOpFactory;
 
   // Assisted injected fields.
-  private final AllRefsWatcher allRefsWatcher;
   private final ProjectState projectState;
   private final IdentifiedUser user;
   private final ReceivePack receivePack;
@@ -363,12 +362,9 @@
   private final ListMultimap<String, String> errors;
 
   private final ListMultimap<String, String> pushOptions;
+  private final ReceivePackRefCache receivePackRefCache;
   private final Map<Change.Id, ReplaceRequest> replaceByChange;
 
-  // Collections lazily populated during processing.
-  private ListMultimap<Change.Id, Ref> refsByChange;
-  private ListMultimap<ObjectId, Ref> refsById;
-
   // Other settings populated during processing.
   private MagicBranchInput magicBranch;
   private boolean newChangeForAllNotInTarget;
@@ -469,7 +465,6 @@
     this.setPrivateOpFactory = setPrivateOpFactory;
 
     // Assisted injected fields.
-    this.allRefsWatcher = allRefsWatcher;
     this.projectState = projectState;
     this.user = user;
     this.receivePack = rp;
@@ -501,6 +496,13 @@
     this.messageSender = messageSender != null ? messageSender : new ReceivePackMessageSender();
     this.resultChangeIds = resultChangeIds;
     this.loggingTags = ImmutableMap.of();
+
+    // TODO(hiesel): Make this decision implicit once vetted
+    boolean useRefCache = config.getBoolean("receive", "enableInMemoryRefCache", true);
+    receivePackRefCache =
+        useRefCache
+            ? ReceivePackRefCache.withAdvertisedRefs(() -> allRefsWatcher.getAllRefs())
+            : ReceivePackRefCache.noCache(receivePack.getRepository().getRefDatabase());
   }
 
   void init() {
@@ -653,17 +655,27 @@
     Task replaceProgress = progress.beginSubTask("updated", UNKNOWN);
 
     List<CreateRequest> newChanges = Collections.emptyList();
-    if (magicBranch != null && magicBranch.cmd.getResult() == NOT_ATTEMPTED) {
-      newChanges = selectNewAndReplacedChangesFromMagicBranch(newProgress);
+    try {
+      if (magicBranch != null && magicBranch.cmd.getResult() == NOT_ATTEMPTED) {
+        try {
+          newChanges = selectNewAndReplacedChangesFromMagicBranch(newProgress);
+        } catch (IOException e) {
+          logger.atSevere().withCause(e).log(
+              "Failed to select new changes in %s", project.getName());
+          return;
+        }
+      }
+
+      // Commit validation has already happened, so any changes without Change-Id are for the
+      // deprecated feature.
+      warnAboutMissingChangeId(newChanges);
+      preparePatchSetsForReplace(newChanges);
+      insertChangesAndPatchSets(newChanges, replaceProgress);
+    } finally {
+      newProgress.end();
+      replaceProgress.end();
     }
 
-    // Commit validation has already happened, so any changes without Change-Id are for the
-    // deprecated feature.
-    warnAboutMissingChangeId(newChanges);
-    preparePatchSetsForReplace(newChanges);
-    insertChangesAndPatchSets(newChanges, replaceProgress);
-    newProgress.end();
-    replaceProgress.end();
     queueSuccessMessages(newChanges);
 
     logger.atFine().log(
@@ -1644,8 +1656,9 @@
     /**
      * returns the destination ref of the magic branch, and populates options in the cmdLineParser.
      */
-    String parse(Repository repo, Set<String> refs, ListMultimap<String, String> pushOptions)
-        throws CmdLineException {
+    String parse(
+        Repository repo, ReceivePackRefCache refCache, ListMultimap<String, String> pushOptions)
+        throws CmdLineException, IOException {
       String ref = RefNames.fullName(MagicBranch.getDestBranchName(cmd.getRefName()));
 
       ListMultimap<String, String> options = LinkedListMultimap.create(pushOptions);
@@ -1675,7 +1688,7 @@
       int split = ref.length();
       for (; ; ) {
         String name = ref.substring(0, split);
-        if (refs.contains(name) || name.equals(head)) {
+        if (refCache.exactRef(name) != null || name.equals(head)) {
           break;
         }
 
@@ -1734,7 +1747,7 @@
    *
    * <p>Assumes we are handling a magic branch here.
    */
-  private void parseMagicBranch(ReceiveCommand cmd) throws PermissionBackendException {
+  private void parseMagicBranch(ReceiveCommand cmd) throws PermissionBackendException, IOException {
     try (TraceTimer traceTimer = newTimer("parseMagicBranch")) {
       logger.atFine().log("Found magic branch %s", cmd.getRefName());
       MagicBranchInput magicBranch = new MagicBranchInput(user, projectState, cmd, labelTypes);
@@ -1743,7 +1756,7 @@
       magicBranch.cmdLineParser = optionParserFactory.create(magicBranch);
 
       try {
-        ref = magicBranch.parse(repo, receivePack.getAdvertisedRefs().keySet(), pushOptions);
+        ref = magicBranch.parse(repo, receivePackRefCache, pushOptions);
       } catch (CmdLineException e) {
         if (!magicBranch.cmdLineParser.wasHelpRequestedByOption()) {
           logger.atFine().log("Invalid branch syntax");
@@ -1775,7 +1788,7 @@
       // review to these branches is allowed even if the branch does not exist yet. This allows to
       // push initial code for review to an empty repository and to review an initial project
       // configuration.
-      if (!receivePack.getAdvertisedRefs().containsKey(ref)
+      if (receivePackRefCache.exactRef(ref) == null
           && !ref.equals(readHEAD(repo))
           && !ref.equals(RefNames.REFS_CONFIG)) {
         logger.atFine().log("Ref %s not found", ref);
@@ -1850,11 +1863,12 @@
             reject(cmd, "cannot use merged with base");
             return;
           }
-          RevCommit branchTip = readBranchTip(magicBranch.dest);
-          if (branchTip == null) {
+          Ref refTip = receivePackRefCache.exactRef(magicBranch.dest.branch());
+          if (refTip == null) {
             reject(cmd, magicBranch.dest.branch() + " not found");
             return;
           }
+          RevCommit branchTip = receivePack.getRevWalk().parseCommit(refTip.getObjectId());
           if (!walk.isMergedInto(tip, branchTip)) {
             reject(cmd, "not merged into branch");
             return;
@@ -1891,8 +1905,9 @@
             }
           }
         } else if (newChangeForAllNotInTarget) {
-          RevCommit branchTip = readBranchTip(magicBranch.dest);
-          if (branchTip != null) {
+          Ref refTip = receivePackRefCache.exactRef(magicBranch.dest.branch());
+          if (refTip != null) {
+            RevCommit branchTip = receivePack.getRevWalk().parseCommit(refTip.getObjectId());
             magicBranch.baseCommit = Collections.singletonList(branchTip);
             logger.atFine().log("Set baseCommit = %s", magicBranch.baseCommit.get(0).name());
           } else {
@@ -1939,7 +1954,7 @@
         newTimer("validateConnected", Metadata.builder().branchName(dest.branch()))) {
       RevWalk walk = receivePack.getRevWalk();
       try {
-        Ref targetRef = receivePack.getAdvertisedRefs().get(dest.branch());
+        Ref targetRef = receivePackRefCache.exactRef(dest.branch());
         if (targetRef == null || targetRef.getObjectId() == null) {
           // The destination branch does not yet exist. Assume the
           // history being sent for review will start it and thus
@@ -1986,14 +2001,6 @@
     }
   }
 
-  private RevCommit readBranchTip(BranchNameKey branch) throws IOException {
-    Ref r = allRefs().get(branch.branch());
-    if (r == null) {
-      return null;
-    }
-    return receivePack.getRevWalk().parseCommit(r.getObjectId());
-  }
-
   /**
    * Update an existing change. If draft comments are to be published, these are validated and may
    * be withheld.
@@ -2001,7 +2008,8 @@
    * @return True if the command succeeded, false if it was rejected.
    */
   private boolean requestReplaceAndValidateComments(
-      ReceiveCommand cmd, boolean checkMergedInto, Change change, RevCommit newCommit) {
+      ReceiveCommand cmd, boolean checkMergedInto, Change change, RevCommit newCommit)
+      throws IOException {
     try (TraceTimer traceTimer = newTimer("requestReplaceAndValidateComments")) {
       if (change.isClosed()) {
         reject(
@@ -2063,14 +2071,14 @@
     }
   }
 
-  private List<CreateRequest> selectNewAndReplacedChangesFromMagicBranch(Task newProgress) {
+  private List<CreateRequest> selectNewAndReplacedChangesFromMagicBranch(Task newProgress)
+      throws IOException {
     try (TraceTimer traceTimer = newTimer("selectNewAndReplacedChangesFromMagicBranch")) {
       logger.atFine().log("Finding new and replaced changes");
       List<CreateRequest> newChanges = new ArrayList<>();
 
-      ListMultimap<ObjectId, Ref> existing = changeRefsById();
       GroupCollector groupCollector =
-          GroupCollector.create(changeRefsById(), psUtil, notesFactory, project.getNameKey());
+          GroupCollector.create(receivePackRefCache, psUtil, notesFactory, project.getNameKey());
 
       BranchCommitValidator validator =
           commitValidatorFactory.create(projectState, magicBranch.dest, user);
@@ -2111,7 +2119,8 @@
           receivePack.getRevWalk().parseBody(c);
           String name = c.name();
           groupCollector.visit(c);
-          Collection<Ref> existingRefs = existing.get(c);
+          Collection<Ref> existingRefs =
+              receivePackRefCache.tipsFromObjectId(c, RefNames.REFS_CHANGES);
 
           if (rejectImplicitMerges) {
             Collections.addAll(mergedParents, c.getParents());
@@ -2275,7 +2284,8 @@
 
             // In case the change look up from the index failed,
             // double check against the existing refs
-            if (foundInExistingRef(existing.get(p.commit))) {
+            if (foundInExistingRef(
+                receivePackRefCache.tipsFromObjectId(p.commit, RefNames.REFS_CHANGES))) {
               if (pending.size() == 1) {
                 reject(magicBranch.cmd, "commit(s) already exists (as current patchset)");
                 return Collections.emptyList();
@@ -2382,7 +2392,7 @@
       for (RevCommit c : magicBranch.baseCommit) {
         receivePack.getRevWalk().markUninteresting(c);
       }
-      Ref targetRef = allRefs().get(magicBranch.dest.branch());
+      Ref targetRef = receivePackRefCache.exactRef(magicBranch.dest.branch());
       if (targetRef != null) {
         logger.atFine().log(
             "Marking target ref %s (%s) uninteresting",
@@ -2397,7 +2407,7 @@
   private void rejectImplicitMerges(Set<RevCommit> mergedParents) throws IOException {
     try (TraceTimer traceTimer = newTimer("rejectImplicitMerges")) {
       if (!mergedParents.isEmpty()) {
-        Ref targetRef = allRefs().get(magicBranch.dest.branch());
+        Ref targetRef = receivePackRefCache.exactRef(magicBranch.dest.branch());
         if (targetRef != null) {
           RevWalk rw = receivePack.getRevWalk();
           RevCommit tip = rw.parseCommit(targetRef.getObjectId());
@@ -2432,13 +2442,15 @@
 
   // Mark all branch tips as uninteresting in the given revwalk,
   // so we get only the new commits when walking rw.
-  private void markHeadsAsUninteresting(RevWalk rw, @Nullable String forRef) {
+  private void markHeadsAsUninteresting(RevWalk rw, @Nullable String forRef) throws IOException {
     try (TraceTimer traceTimer =
         newTimer("markHeadsAsUninteresting", Metadata.builder().branchName(forRef))) {
       int i = 0;
-      for (Ref ref : allRefs().values()) {
-        if ((ref.getName().startsWith(R_HEADS) || ref.getName().equals(forRef))
-            && ref.getObjectId() != null) {
+      for (Ref ref :
+          Iterables.concat(
+              receivePackRefCache.byPrefix(R_HEADS),
+              Collections.singletonList(receivePackRefCache.exactRef(forRef)))) {
+        if (ref != null && ref.getObjectId() != null) {
           try {
             rw.markUninteresting(rw.parseCommit(ref.getObjectId()));
             i++;
@@ -2703,7 +2715,8 @@
     ReplaceOp replaceOp;
 
     ReplaceRequest(
-        Change.Id toChange, RevCommit newCommit, ReceiveCommand cmd, boolean checkMergedInto) {
+        Change.Id toChange, RevCommit newCommit, ReceiveCommand cmd, boolean checkMergedInto)
+        throws IOException {
       this.ontoChange = toChange;
       this.newCommitId = newCommit.copy();
       this.inputCommand = requireNonNull(cmd);
@@ -2715,11 +2728,12 @@
         revCommit = null;
       }
       revisions = HashBiMap.create();
-      for (Ref ref : refs(toChange)) {
+      for (Ref ref : receivePackRefCache.byPrefix(RefNames.changeRefPrefix(toChange))) {
         try {
-          revisions.forcePut(
-              receivePack.getRevWalk().parseCommit(ref.getObjectId()),
-              PatchSet.Id.fromRef(ref.getName()));
+          PatchSet.Id psId = PatchSet.Id.fromRef(ref.getName());
+          if (psId != null) {
+            revisions.forcePut(receivePack.getRevWalk().parseCommit(ref.getObjectId()), psId);
+          }
         } catch (IOException err) {
           logger.atWarning().withCause(err).log(
               "Project %s contains invalid change ref %s", project.getName(), ref.getName());
@@ -2785,6 +2799,16 @@
         Change change = notes.getChange();
         priorPatchSet = change.currentPatchSetId();
         if (!revisions.containsValue(priorPatchSet)) {
+          logger.atWarning().log(
+              "Change %d is missing revision for patch set %s"
+                  + " (it has revisions for these patch sets: %s)",
+              change.getChangeId(),
+              priorPatchSet.getId(),
+              Iterables.toString(
+                  revisions.values().stream()
+                      .limit(100) // Enough for "normal" changes.
+                      .map(PatchSet.Id::getId)
+                      .collect(Collectors.toList())));
           reject(inputCommand, "change " + ontoChange + " missing revisions");
           return false;
         }
@@ -2812,11 +2836,16 @@
           return false;
         }
 
-        for (Ref r : receivePack.getRepository().getRefDatabase().getRefsByPrefix("refs/changes")) {
-          if (r.getObjectId().equals(newCommit)) {
-            reject(inputCommand, "commit already exists (in the project)");
-            return false;
-          }
+        List<Ref> existingChangesWithSameCommit =
+            receivePackRefCache.tipsFromObjectId(newCommit, RefNames.REFS_CHANGES);
+        if (!existingChangesWithSameCommit.isEmpty()) {
+          // TODO(hiesel, hanwen): Remove this check entirely when Gerrit requires change IDs
+          //  without the option to turn that off.
+          reject(
+              inputCommand,
+              "commit already exists (in the project): "
+                  + existingChangesWithSameCommit.get(0).getName());
+          return false;
         }
 
         try (TraceTimer traceTimer2 = newTimer("validateNewPatchSetNoteDb#isMergedInto")) {
@@ -2950,14 +2979,20 @@
     private void newPatchSet() throws IOException {
       try (TraceTimer traceTimer = newTimer("newPatchSet")) {
         RevCommit newCommit = receivePack.getRevWalk().parseCommit(newCommitId);
-        psId =
-            ChangeUtil.nextPatchSetIdFromAllRefsMap(
-                allRefs(), notes.getChange().currentPatchSetId());
+        psId = nextPatchSetId(notes.getChange().currentPatchSetId());
         info = patchSetInfoFactory.get(receivePack.getRevWalk(), newCommit, psId);
         cmd = new ReceiveCommand(ObjectId.zeroId(), newCommitId, psId.toRefName());
       }
     }
 
+    private PatchSet.Id nextPatchSetId(PatchSet.Id psId) throws IOException {
+      PatchSet.Id next = ChangeUtil.nextPatchSetId(psId);
+      while (receivePackRefCache.exactRef(next.toRefName()) != null) {
+        next = ChangeUtil.nextPatchSetId(next);
+      }
+      return next;
+    }
+
     void addOps(BatchUpdate bu, @Nullable Task progress) throws IOException {
       try (TraceTimer traceTimer = newTimer("addOps")) {
         if (magicBranch != null && magicBranch.edit) {
@@ -3091,45 +3126,6 @@
     }
   }
 
-  private List<Ref> refs(Change.Id changeId) {
-    return refsByChange().get(changeId);
-  }
-
-  private void initChangeRefMaps() {
-    if (refsByChange != null) {
-      return;
-    }
-
-    try (TraceTimer traceTimer = newTimer("initChangeRefMaps")) {
-      int estRefsPerChange = 4;
-      refsById = MultimapBuilder.hashKeys().arrayListValues().build();
-      refsByChange =
-          MultimapBuilder.hashKeys(allRefs().size() / estRefsPerChange)
-              .arrayListValues(estRefsPerChange)
-              .build();
-      for (Ref ref : allRefs().values()) {
-        ObjectId obj = ref.getObjectId();
-        if (obj != null) {
-          PatchSet.Id psId = PatchSet.Id.fromRef(ref.getName());
-          if (psId != null) {
-            refsById.put(obj, ref);
-            refsByChange.put(psId.changeId(), ref);
-          }
-        }
-      }
-    }
-  }
-
-  private ListMultimap<Change.Id, Ref> refsByChange() {
-    initChangeRefMaps();
-    return refsByChange;
-  }
-
-  private ListMultimap<ObjectId, Ref> changeRefsById() {
-    initChangeRefMaps();
-    return refsById;
-  }
-
   private static boolean parentsEqual(RevCommit a, RevCommit b) {
     if (a.getParentCount() != b.getParentCount()) {
       return false;
@@ -3214,7 +3210,6 @@
         if (!(parsedObject instanceof RevCommit)) {
           return;
         }
-        ListMultimap<ObjectId, Ref> existing = changeRefsById();
         walk.markStart((RevCommit) parsedObject);
         markHeadsAsUninteresting(walk, cmd.getRefName());
         int limit = receiveConfig.maxBatchCommits;
@@ -3231,7 +3226,7 @@
                     "more than %d commits, and %s not set", limit, PUSH_OPTION_SKIP_VALIDATION));
             return;
           }
-          if (existing.keySet().contains(c)) {
+          if (!receivePackRefCache.tipsFromObjectId(c, RefNames.REFS_CHANGES).isEmpty()) {
             continue;
           }
 
@@ -3281,26 +3276,34 @@
                   rw.markUninteresting(rw.parseCommit(cmd.getOldId()));
                 }
 
-                ListMultimap<ObjectId, Ref> byCommit = changeRefsById();
                 Map<Change.Key, ChangeNotes> byKey = null;
                 List<ReplaceRequest> replaceAndClose = new ArrayList<>();
 
                 int existingPatchSets = 0;
                 int newPatchSets = 0;
+                RequestId submissionId = null;
                 COMMIT:
                 for (RevCommit c; (c = rw.next()) != null; ) {
                   rw.parseBody(c);
 
-                  for (Ref ref : byCommit.get(c.copy())) {
+                  for (Ref ref :
+                      receivePackRefCache.tipsFromObjectId(c.copy(), RefNames.REFS_CHANGES)) {
                     PatchSet.Id psId = PatchSet.Id.fromRef(ref.getName());
                     Optional<ChangeNotes> notes = getChangeNotes(psId.changeId());
+                    if (submissionId == null) {
+                      submissionId = new RequestId(psId.changeId().toString());
+                    }
                     if (notes.isPresent() && notes.get().getChange().getDest().equals(branch)) {
                       existingPatchSets++;
                       bu.addOp(notes.get().getChangeId(), setPrivateOpFactory.create(false, null));
                       bu.addOp(
                           psId.changeId(),
                           mergedByPushOpFactory.create(
-                              requestScopePropagator, psId, refName, newTip.getId().getName()));
+                              requestScopePropagator,
+                              psId,
+                              submissionId,
+                              refName,
+                              newTip.getId().getName()));
                       continue COMMIT;
                     }
                   }
@@ -3329,13 +3332,20 @@
                     logger.atFine().log("Not closing %s because validation failed", id);
                     continue;
                   }
+                  if (submissionId == null) {
+                    submissionId = new RequestId(id.toString());
+                  }
                   req.addOps(bu, null);
                   bu.addOp(id, setPrivateOpFactory.create(false, null));
                   bu.addOp(
                       id,
                       mergedByPushOpFactory
                           .create(
-                              requestScopePropagator, req.psId, refName, newTip.getId().getName())
+                              requestScopePropagator,
+                              req.psId,
+                              submissionId,
+                              refName,
+                              newTip.getId().getName())
                           .setPatchSetProvider(req.replaceOp::getPatchSet));
                   bu.addOp(id, new ChangeProgressOp(progress));
                   ids.add(id);
@@ -3403,13 +3413,6 @@
     }
   }
 
-  // allRefsWatcher hooks into the protocol negotation to get a list of all known refs.
-  // This is used as a cache of ref -> sha1 values, and to build an inverse index
-  // of (change => list of refs) and a (SHA1 => refs).
-  private Map<String, Ref> allRefs() {
-    return allRefsWatcher.getAllRefs();
-  }
-
   private TraceTimer newTimer(String name) {
     return newTimer(getClass(), name);
   }
diff --git a/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHook.java b/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHook.java
index 83bf554..6c1f097 100644
--- a/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHook.java
+++ b/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHook.java
@@ -18,14 +18,19 @@
 
 import com.google.common.collect.Sets;
 import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.exceptions.StorageException;
+import com.google.gerrit.index.query.Predicate;
 import com.google.gerrit.server.git.HookUtil;
 import com.google.gerrit.server.index.change.ChangeField;
 import com.google.gerrit.server.query.change.ChangeData;
+import com.google.gerrit.server.query.change.ChangeStatusPredicate;
 import com.google.gerrit.server.query.change.InternalChangeQuery;
+import com.google.gerrit.server.query.change.OwnerPredicate;
+import com.google.gerrit.server.query.change.ProjectPredicate;
 import com.google.gerrit.server.util.MagicBranch;
 import com.google.inject.Provider;
 import java.io.IOException;
@@ -65,11 +70,13 @@
 
   private final Provider<InternalChangeQuery> queryProvider;
   private final Project.NameKey projectName;
+  private final Account.Id user;
 
   public ReceiveCommitsAdvertiseRefsHook(
-      Provider<InternalChangeQuery> queryProvider, Project.NameKey projectName) {
+      Provider<InternalChangeQuery> queryProvider, Project.NameKey projectName, Account.Id user) {
     this.queryProvider = queryProvider;
     this.projectName = projectName;
+    this.user = user;
   }
 
   @Override
@@ -90,7 +97,9 @@
 
   private Set<ObjectId> advertiseOpenChanges(Repository repo)
       throws ServiceMayNotContinueException {
-    // Advertise some recent open changes, in case a commit is based on one.
+    // Advertise the user's most recent open changes. It's likely that the user has one of these in
+    // their local repo and they can serve as starting points to figure out the common ancestor of
+    // what the client and server have in common.
     int limit = 32;
     try {
       Set<ObjectId> r = Sets.newHashSetWithExpectedSize(limit);
@@ -105,7 +114,11 @@
                   ChangeField.PATCH_SET)
               .enforceVisibility(true)
               .setLimit(limit)
-              .byProjectOpen(projectName)) {
+              .query(
+                  Predicate.and(
+                      new ProjectPredicate(projectName.get()),
+                      ChangeStatusPredicate.open(),
+                      new OwnerPredicate(user)))) {
         PatchSet ps = cd.currentPatchSet();
         if (ps != null) {
           // Ensure we actually observed a patch set ref pointing to this
diff --git a/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHookChain.java b/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHookChain.java
index 76f6b04..fae1401 100644
--- a/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHookChain.java
+++ b/java/com/google/gerrit/server/git/receive/ReceiveCommitsAdvertiseRefsHookChain.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.server.git.receive;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.server.query.change.InternalChangeQuery;
 import com.google.inject.Provider;
@@ -35,8 +36,9 @@
   public static AdvertiseRefsHook create(
       AllRefsWatcher allRefsWatcher,
       Provider<InternalChangeQuery> queryProvider,
-      Project.NameKey projectName) {
-    return create(allRefsWatcher, queryProvider, projectName, false);
+      Project.NameKey projectName,
+      Account.Id user) {
+    return create(allRefsWatcher, queryProvider, projectName, user, false);
   }
 
   /**
@@ -47,18 +49,19 @@
    */
   @VisibleForTesting
   public static AdvertiseRefsHook createForTest(
-      Provider<InternalChangeQuery> queryProvider, Project.NameKey projectName) {
-    return create(new AllRefsWatcher(), queryProvider, projectName, true);
+      Provider<InternalChangeQuery> queryProvider, Project.NameKey projectName, Account.Id user) {
+    return create(new AllRefsWatcher(), queryProvider, projectName, user, true);
   }
 
   private static AdvertiseRefsHook create(
       AllRefsWatcher allRefsWatcher,
       Provider<InternalChangeQuery> queryProvider,
       Project.NameKey projectName,
+      Account.Id user,
       boolean skipHackPushNegotiateHook) {
     List<AdvertiseRefsHook> advHooks = new ArrayList<>();
     advHooks.add(allRefsWatcher);
-    advHooks.add(new ReceiveCommitsAdvertiseRefsHook(queryProvider, projectName));
+    advHooks.add(new ReceiveCommitsAdvertiseRefsHook(queryProvider, projectName, user));
     if (!skipHackPushNegotiateHook) {
       advHooks.add(new HackPushNegotiateHook());
     }
diff --git a/java/com/google/gerrit/server/git/receive/ReceivePackRefCache.java b/java/com/google/gerrit/server/git/receive/ReceivePackRefCache.java
new file mode 100644
index 0000000..376ab2d
--- /dev/null
+++ b/java/com/google/gerrit/server/git/receive/ReceivePackRefCache.java
@@ -0,0 +1,174 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.git.receive;
+
+import static com.google.common.collect.ImmutableList.toImmutableList;
+
+import com.google.common.base.Supplier;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ListMultimap;
+import com.google.common.collect.MultimapBuilder;
+import com.google.gerrit.entities.Change;
+import com.google.gerrit.entities.RefNames;
+import java.io.IOException;
+import java.util.Map;
+import org.eclipse.jgit.annotations.Nullable;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.RefDatabase;
+
+/**
+ * Simple cache for accessing refs by name, prefix or {@link ObjectId}. Intended to be used when
+ * processing a {@code git push}.
+ *
+ * <p>This class is not thread safe.
+ */
+public interface ReceivePackRefCache {
+
+  /**
+   * Returns an instance that delegates all calls to the provided {@link RefDatabase}. To be used in
+   * tests or when the ref database is fast with forward (name to {@link ObjectId}) and inverse
+   * ({@code ObjectId} to name) lookups.
+   */
+  static ReceivePackRefCache noCache(RefDatabase delegate) {
+    return new NoCache(delegate);
+  }
+
+  /**
+   * Returns an instance that answers calls based on refs previously advertised and captured in
+   * {@link AllRefsWatcher}. Speeds up inverse lookups by building a {@code Map<ObjectId,
+   * List<Ref>>} and a {@code Map<Change.Id, List<Ref>>}.
+   *
+   * <p>This implementation speeds up lookups when the ref database does not support inverse ({@code
+   * ObjectId} to name) lookups.
+   */
+  static ReceivePackRefCache withAdvertisedRefs(Supplier<Map<String, Ref>> allRefsSupplier) {
+    return new WithAdvertisedRefs(allRefsSupplier);
+  }
+
+  /** Returns a list of refs whose name starts with {@code prefix} that point to {@code id}. */
+  ImmutableList<Ref> tipsFromObjectId(ObjectId id, @Nullable String prefix) throws IOException;
+
+  /** Returns all refs whose name starts with {@code prefix}. */
+  ImmutableList<Ref> byPrefix(String prefix) throws IOException;
+
+  /** Returns a ref whose name matches {@code ref} or {@code null} if such a ref does not exist. */
+  @Nullable
+  Ref exactRef(String ref) throws IOException;
+
+  class NoCache implements ReceivePackRefCache {
+    private final RefDatabase delegate;
+
+    private NoCache(RefDatabase delegate) {
+      this.delegate = delegate;
+    }
+
+    @Override
+    public ImmutableList<Ref> tipsFromObjectId(ObjectId id, @Nullable String prefix)
+        throws IOException {
+      return delegate.getTipsWithSha1(id).stream()
+          .filter(r -> prefix == null || r.getName().startsWith(prefix))
+          .collect(toImmutableList());
+    }
+
+    @Override
+    public ImmutableList<Ref> byPrefix(String prefix) throws IOException {
+      return delegate.getRefsByPrefix(prefix).stream().collect(toImmutableList());
+    }
+
+    @Override
+    @Nullable
+    public Ref exactRef(String name) throws IOException {
+      return delegate.exactRef(name);
+    }
+  }
+
+  class WithAdvertisedRefs implements ReceivePackRefCache {
+    /** We estimate that a change has an average of 4 patch sets plus the meta ref. */
+    private static final int ESTIMATED_NUMBER_OF_REFS_PER_CHANGE = 5;
+
+    private final Supplier<Map<String, Ref>> allRefsSupplier;
+
+    // Collections lazily populated during processing.
+    private Map<String, Ref> allRefs;
+    /** Contains only patch set refs. */
+    private ListMultimap<Change.Id, Ref> refsByChange;
+    /** Contains all refs. */
+    private ListMultimap<ObjectId, Ref> refsByObjectId;
+
+    private WithAdvertisedRefs(Supplier<Map<String, Ref>> allRefsSupplier) {
+      this.allRefsSupplier = allRefsSupplier;
+    }
+
+    @Override
+    public ImmutableList<Ref> tipsFromObjectId(ObjectId id, String prefix) {
+      lazilyInitRefMaps();
+      return refsByObjectId.get(id).stream()
+          .filter(r -> prefix == null || r.getName().startsWith(prefix))
+          .collect(toImmutableList());
+    }
+
+    @Override
+    public ImmutableList<Ref> byPrefix(String prefix) {
+      lazilyInitRefMaps();
+      if (RefNames.isRefsChanges(prefix)) {
+        Change.Id cId = Change.Id.fromRefPart(prefix);
+        if (cId != null) {
+          return refsByChange.get(cId).stream()
+              .filter(r -> r.getName().startsWith(prefix))
+              .collect(toImmutableList());
+        }
+      }
+      return allRefs().values().stream()
+          .filter(r -> r.getName().startsWith(prefix))
+          .collect(toImmutableList());
+    }
+
+    @Override
+    @Nullable
+    public Ref exactRef(String name) {
+      return allRefs().get(name);
+    }
+
+    private Map<String, Ref> allRefs() {
+      if (allRefs == null) {
+        allRefs = allRefsSupplier.get();
+      }
+      return allRefs;
+    }
+
+    private void lazilyInitRefMaps() {
+      if (refsByChange != null) {
+        return;
+      }
+
+      refsByObjectId = MultimapBuilder.hashKeys().arrayListValues().build();
+      refsByChange =
+          MultimapBuilder.hashKeys(allRefs().size() / ESTIMATED_NUMBER_OF_REFS_PER_CHANGE)
+              .arrayListValues(ESTIMATED_NUMBER_OF_REFS_PER_CHANGE)
+              .build();
+      for (Ref ref : allRefs().values()) {
+        ObjectId objectId = ref.getObjectId();
+        if (objectId != null) {
+          refsByObjectId.put(objectId, ref);
+          Change.Id changeId = Change.Id.fromRef(ref.getName());
+          if (changeId != null) {
+            refsByChange.put(changeId, ref);
+          }
+        }
+      }
+    }
+  }
+}
diff --git a/java/com/google/gerrit/server/git/receive/ReplaceOp.java b/java/com/google/gerrit/server/git/receive/ReplaceOp.java
index e95cf3b..6c0d5d3 100644
--- a/java/com/google/gerrit/server/git/receive/ReplaceOp.java
+++ b/java/com/google/gerrit/server/git/receive/ReplaceOp.java
@@ -61,6 +61,7 @@
 import com.google.gerrit.server.extensions.events.RevisionCreated;
 import com.google.gerrit.server.git.MergedByPushOp;
 import com.google.gerrit.server.git.receive.ReceiveCommits.MagicBranchInput;
+import com.google.gerrit.server.logging.RequestId;
 import com.google.gerrit.server.mail.MailUtil.MailRecipients;
 import com.google.gerrit.server.mail.send.ReplacePatchSetSender;
 import com.google.gerrit.server.notedb.ChangeNotes;
@@ -236,7 +237,11 @@
       if (mergedInto != null) {
         mergedByPushOp =
             mergedByPushOpFactory.create(
-                requestScopePropagator, patchSetId, mergedInto, mergeResultRevId);
+                requestScopePropagator,
+                patchSetId,
+                new RequestId(patchSetId.changeId().toString()),
+                mergedInto,
+                mergeResultRevId);
       }
     }
 
diff --git a/java/com/google/gerrit/server/index/StalenessCheckResult.java b/java/com/google/gerrit/server/index/StalenessCheckResult.java
new file mode 100644
index 0000000..fe35e6e
--- /dev/null
+++ b/java/com/google/gerrit/server/index/StalenessCheckResult.java
@@ -0,0 +1,41 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.index;
+
+import com.google.auto.value.AutoValue;
+import com.google.errorprone.annotations.FormatMethod;
+import java.util.Optional;
+
+/** Structured result of a staleness check. */
+@AutoValue
+public abstract class StalenessCheckResult {
+
+  public static StalenessCheckResult notStale() {
+    return new AutoValue_StalenessCheckResult(false, Optional.empty());
+  }
+
+  public static StalenessCheckResult stale(String reason) {
+    return new AutoValue_StalenessCheckResult(true, Optional.of(reason));
+  }
+
+  @FormatMethod
+  public static StalenessCheckResult stale(String reason, Object... args) {
+    return stale(String.format(reason, args));
+  }
+
+  public abstract boolean isStale();
+
+  public abstract Optional<String> reason();
+}
diff --git a/java/com/google/gerrit/server/index/account/AccountIndexerImpl.java b/java/com/google/gerrit/server/index/account/AccountIndexerImpl.java
index b908846..5aafec8 100644
--- a/java/com/google/gerrit/server/index/account/AccountIndexerImpl.java
+++ b/java/com/google/gerrit/server/index/account/AccountIndexerImpl.java
@@ -23,6 +23,7 @@
 import com.google.gerrit.index.Index;
 import com.google.gerrit.server.account.AccountCache;
 import com.google.gerrit.server.account.AccountState;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.logging.TraceContext;
 import com.google.gerrit.server.logging.TraceContext.TraceTimer;
@@ -116,7 +117,9 @@
   @Override
   public boolean reindexIfStale(Account.Id id) {
     try {
-      if (stalenessChecker.isStale(id)) {
+      StalenessCheckResult stalenessCheckResult = stalenessChecker.check(id);
+      if (stalenessCheckResult.isStale()) {
+        logger.atInfo().log("Reindexing stale document %s", stalenessCheckResult);
         index(id);
         return true;
       }
diff --git a/java/com/google/gerrit/server/index/account/StalenessChecker.java b/java/com/google/gerrit/server/index/account/StalenessChecker.java
index aad9527..50fdcde 100644
--- a/java/com/google/gerrit/server/index/account/StalenessChecker.java
+++ b/java/com/google/gerrit/server/index/account/StalenessChecker.java
@@ -35,6 +35,7 @@
 import com.google.gerrit.server.config.AllUsersNameProvider;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.index.IndexUtils;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
@@ -87,16 +88,16 @@
     this.indexConfig = indexConfig;
   }
 
-  public boolean isStale(Account.Id id) throws IOException {
+  public StalenessCheckResult check(Account.Id id) throws IOException {
     AccountIndex i = indexes.getSearchIndex();
     if (i == null) {
       // No index; caller couldn't do anything if it is stale.
-      return false;
+      return StalenessCheckResult.notStale();
     }
     if (!i.getSchema().hasField(AccountField.REF_STATE)
         || !i.getSchema().hasField(AccountField.EXTERNAL_ID_STATE)) {
       // Index version not new enough for this check.
-      return false;
+      return StalenessCheckResult.notStale();
     }
 
     boolean useLegacyNumericFields = i.getSchema().useLegacyNumericFields();
@@ -112,7 +113,11 @@
         Ref ref = repo.exactRef(RefNames.refsUsers(id));
 
         // Stale if the account actually exists.
-        return ref != null;
+        if (ref == null) {
+          return StalenessCheckResult.notStale();
+        }
+        return StalenessCheckResult.stale(
+            "Document missing in index, but found %s in the repo", ref);
       }
     }
 
@@ -124,8 +129,9 @@
           e.getKey().get().equals(AllUsersNameProvider.DEFAULT) ? allUsersName : e.getKey();
       try (Repository repo = repoManager.openRepository(repoName)) {
         if (!e.getValue().match(repo)) {
-          // Ref was modified since the account was indexed.
-          return true;
+          return StalenessCheckResult.stale(
+              "Ref was modified since the account was indexed (%s != %s)",
+              e.getValue(), repo.exactRef(e.getValue().ref()));
         }
       }
     }
@@ -134,17 +140,22 @@
     ListMultimap<ObjectId, ObjectId> extIdStates =
         parseExternalIdStates(result.get().getValue(AccountField.EXTERNAL_ID_STATE));
     if (extIdStates.size() != extIds.size()) {
-      // External IDs of the account were modified since the account was indexed.
-      return true;
+      return StalenessCheckResult.stale(
+          "External IDs of the account were modified since the account was indexed. (%s != %s)",
+          extIdStates.size(), extIds.size());
     }
     for (ExternalId extId : extIds) {
+      if (!extIdStates.containsKey(extId.key().sha1())) {
+        return StalenessCheckResult.stale("External ID missing: %s", extId.key().sha1());
+      }
       if (!extIdStates.containsEntry(extId.key().sha1(), extId.blobId())) {
-        // External IDs of the account were modified since the account was indexed.
-        return true;
+        return StalenessCheckResult.stale(
+            "External ID has unexpected value. (%s != %s)",
+            extIdStates.get(extId.key().sha1()), extId.blobId());
       }
     }
 
-    return false;
+    return StalenessCheckResult.notStale();
   }
 
   public static ListMultimap<ObjectId, ObjectId> parseExternalIdStates(
diff --git a/java/com/google/gerrit/server/index/change/ChangeIndexer.java b/java/com/google/gerrit/server/index/change/ChangeIndexer.java
index f6d86bf..5211a07 100644
--- a/java/com/google/gerrit/server/index/change/ChangeIndexer.java
+++ b/java/com/google/gerrit/server/index/change/ChangeIndexer.java
@@ -28,6 +28,7 @@
 import com.google.gerrit.index.Index;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.gerrit.server.index.IndexExecutor;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.logging.TraceContext;
 import com.google.gerrit.server.logging.TraceContext.TraceTimer;
@@ -432,7 +433,9 @@
     public Boolean callImpl() throws Exception {
       remove();
       try {
-        if (stalenessChecker.isStale(id)) {
+        StalenessCheckResult stalenessCheckResult = stalenessChecker.check(id);
+        if (stalenessCheckResult.isStale()) {
+          logger.atInfo().log("Reindexing stale document %s", stalenessCheckResult);
           indexImpl(changeDataFactory.create(project, id));
           return true;
         }
diff --git a/java/com/google/gerrit/server/index/change/ReindexAfterRefUpdate.java b/java/com/google/gerrit/server/index/change/ReindexAfterRefUpdate.java
index f6d3b6f..5efa065 100644
--- a/java/com/google/gerrit/server/index/change/ReindexAfterRefUpdate.java
+++ b/java/com/google/gerrit/server/index/change/ReindexAfterRefUpdate.java
@@ -76,7 +76,7 @@
     this.accountCache = accountCache;
     this.indexer = indexer;
     this.executor = executor;
-    this.enabled = cfg.getBoolean("index", null, "reindexAfterRefUpdate", true);
+    this.enabled = cfg.getBoolean("index", "change", "indexMergeable", true);
   }
 
   @Override
diff --git a/java/com/google/gerrit/server/index/change/StalenessChecker.java b/java/com/google/gerrit/server/index/change/StalenessChecker.java
index 47fd7ba..236163d 100644
--- a/java/com/google/gerrit/server/index/change/StalenessChecker.java
+++ b/java/com/google/gerrit/server/index/change/StalenessChecker.java
@@ -35,6 +35,7 @@
 import com.google.gerrit.index.IndexConfig;
 import com.google.gerrit.index.RefState;
 import com.google.gerrit.server.git.GitRepositoryManager;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -68,27 +69,28 @@
     this.indexConfig = indexConfig;
   }
 
-  public boolean isStale(Change.Id id) {
+  public StalenessCheckResult check(Change.Id id) {
     ChangeIndex i = indexes.getSearchIndex();
     if (i == null) {
-      return false; // No index; caller couldn't do anything if it is stale.
+      return StalenessCheckResult
+          .notStale(); // No index; caller couldn't do anything if it is stale.
     }
     if (!i.getSchema().hasField(ChangeField.REF_STATE)
         || !i.getSchema().hasField(ChangeField.REF_STATE_PATTERN)) {
-      return false; // Index version not new enough for this check.
+      return StalenessCheckResult.notStale(); // Index version not new enough for this check.
     }
 
     Optional<ChangeData> result =
         i.get(id, IndexedChangeQuery.createOptions(indexConfig, 0, 1, FIELDS));
     if (!result.isPresent()) {
-      return true; // Not in index, but caller wants it to be.
+      return StalenessCheckResult.stale("Document %s missing from index", id);
     }
     ChangeData cd = result.get();
-    return isStale(repoManager, id, parseStates(cd), parsePatterns(cd));
+    return check(repoManager, id, parseStates(cd), parsePatterns(cd));
   }
 
   @UsedAt(UsedAt.Project.GOOGLE)
-  public static boolean isStale(
+  public static StalenessCheckResult check(
       GitRepositoryManager repoManager,
       Change.Id id,
       SetMultimap<Project.NameKey, RefState> states,
@@ -97,7 +99,7 @@
   }
 
   @VisibleForTesting
-  static boolean refsAreStale(
+  static StalenessCheckResult refsAreStale(
       GitRepositoryManager repoManager,
       Change.Id id,
       SetMultimap<Project.NameKey, RefState> states,
@@ -105,12 +107,13 @@
     Set<Project.NameKey> projects = Sets.union(states.keySet(), patterns.keySet());
 
     for (Project.NameKey p : projects) {
-      if (refsAreStale(repoManager, id, p, states, patterns)) {
-        return true;
+      StalenessCheckResult result = refsAreStale(repoManager, id, p, states, patterns);
+      if (result.isStale()) {
+        return result;
       }
     }
 
-    return false;
+    return StalenessCheckResult.notStale();
   }
 
   private SetMultimap<Project.NameKey, RefState> parseStates(ChangeData cd) {
@@ -136,7 +139,7 @@
     return result;
   }
 
-  private static boolean refsAreStale(
+  private static StalenessCheckResult refsAreStale(
       GitRepositoryManager repoManager,
       Change.Id id,
       Project.NameKey project,
@@ -146,18 +149,22 @@
       Set<RefState> states = allStates.get(project);
       for (RefState state : states) {
         if (!state.match(repo)) {
-          return true;
+          return StalenessCheckResult.stale(
+              "Ref states don't match for document %s (%s != %s)",
+              id, state, repo.exactRef(state.ref()));
         }
       }
       for (RefStatePattern pattern : allPatterns.get(project)) {
         if (!pattern.match(repo, states)) {
-          return true;
+          return StalenessCheckResult.stale(
+              "Ref patterns don't match for document %s. Pattern: %s States: %s",
+              id, pattern, states);
         }
       }
-      return false;
+      return StalenessCheckResult.notStale();
     } catch (IOException e) {
       logger.atWarning().withCause(e).log("error checking staleness of %s in %s", id, project);
-      return true;
+      return StalenessCheckResult.stale("Exceptions while processing document %s", e.getMessage());
     }
   }
 
diff --git a/java/com/google/gerrit/server/index/group/GroupIndexerImpl.java b/java/com/google/gerrit/server/index/group/GroupIndexerImpl.java
index 790066d..70dc8fa 100644
--- a/java/com/google/gerrit/server/index/group/GroupIndexerImpl.java
+++ b/java/com/google/gerrit/server/index/group/GroupIndexerImpl.java
@@ -23,6 +23,7 @@
 import com.google.gerrit.index.Index;
 import com.google.gerrit.server.account.GroupCache;
 import com.google.gerrit.server.group.InternalGroup;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.gerrit.server.logging.Metadata;
 import com.google.gerrit.server.logging.TraceContext;
 import com.google.gerrit.server.logging.TraceContext.TraceTimer;
@@ -116,7 +117,9 @@
   @Override
   public boolean reindexIfStale(AccountGroup.UUID uuid) {
     try {
-      if (stalenessChecker.isStale(uuid)) {
+      StalenessCheckResult stalenessCheckResult = stalenessChecker.check(uuid);
+      if (stalenessCheckResult.isStale()) {
+        logger.atInfo().log("Reindexing stale document %s", stalenessCheckResult);
         index(uuid);
         return true;
       }
diff --git a/java/com/google/gerrit/server/index/group/StalenessChecker.java b/java/com/google/gerrit/server/index/group/StalenessChecker.java
index 3a721c3..54a6f85 100644
--- a/java/com/google/gerrit/server/index/group/StalenessChecker.java
+++ b/java/com/google/gerrit/server/index/group/StalenessChecker.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.index.query.FieldBundle;
 import com.google.gerrit.server.config.AllUsersName;
 import com.google.gerrit.server.git.GitRepositoryManager;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
@@ -59,10 +60,11 @@
     this.allUsers = allUsers;
   }
 
-  public boolean isStale(AccountGroup.UUID uuid) throws IOException {
+  public StalenessCheckResult check(AccountGroup.UUID uuid) throws IOException {
     GroupIndex i = indexes.getSearchIndex();
     if (i == null) {
-      return false; // No index; caller couldn't do anything if it is stale.
+      // No index; caller couldn't do anything if it is stale.
+      return StalenessCheckResult.notStale();
     }
 
     Optional<FieldBundle> result =
@@ -73,14 +75,23 @@
         Ref ref = repo.exactRef(RefNames.refsGroups(uuid));
 
         // Stale if the group actually exists.
-        return ref != null;
+        if (ref == null) {
+          return StalenessCheckResult.notStale();
+        }
+        return StalenessCheckResult.stale(
+            "Document missing in index, but found %s in the repo", ref);
       }
     }
 
     try (Repository repo = repoManager.openRepository(allUsers)) {
       Ref ref = repo.exactRef(RefNames.refsGroups(uuid));
       ObjectId head = ref == null ? ObjectId.zeroId() : ref.getObjectId();
-      return !head.equals(ObjectId.fromString(result.get().getValue(GroupField.REF_STATE), 0));
+      ObjectId idFromIndex = ObjectId.fromString(result.get().getValue(GroupField.REF_STATE), 0);
+      if (head.equals(idFromIndex)) {
+        return StalenessCheckResult.notStale();
+      }
+      return StalenessCheckResult.stale(
+          "Document has unexpected ref state (%s != %s)", head, idFromIndex);
     }
   }
 }
diff --git a/java/com/google/gerrit/server/index/project/StalenessChecker.java b/java/com/google/gerrit/server/index/project/StalenessChecker.java
index e4c1a7d..e325a33 100644
--- a/java/com/google/gerrit/server/index/project/StalenessChecker.java
+++ b/java/com/google/gerrit/server/index/project/StalenessChecker.java
@@ -27,6 +27,7 @@
 import com.google.gerrit.index.project.ProjectIndex;
 import com.google.gerrit.index.project.ProjectIndexCollection;
 import com.google.gerrit.index.query.FieldBundle;
+import com.google.gerrit.server.index.StalenessCheckResult;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.inject.Inject;
 import java.util.Optional;
@@ -47,17 +48,18 @@
     this.indexConfig = indexConfig;
   }
 
-  public boolean isStale(Project.NameKey project) {
+  public StalenessCheckResult check(Project.NameKey project) {
     ProjectData projectData = projectCache.get(project).toProjectData();
     ProjectIndex i = indexes.getSearchIndex();
     if (i == null) {
-      return false; // No index; caller couldn't do anything if it is stale.
+      return StalenessCheckResult
+          .notStale(); // No index; caller couldn't do anything if it is stale.
     }
 
     Optional<FieldBundle> result =
         i.getRaw(project, QueryOptions.create(indexConfig, 0, 1, FIELDS));
     if (!result.isPresent()) {
-      return true;
+      return StalenessCheckResult.stale("Document %s missing from index", project);
     }
 
     SetMultimap<Project.NameKey, RefState> indexedRefStates =
@@ -73,6 +75,10 @@
                     p.getProject().getNameKey(),
                     RefState.create(RefNames.REFS_CONFIG, p.getProject().getConfigRefState())));
 
-    return !currentRefStates.equals(indexedRefStates);
+    if (currentRefStates.equals(indexedRefStates)) {
+      return StalenessCheckResult.notStale();
+    }
+    return StalenessCheckResult.stale(
+        "Document has unexpected ref states (%s != %s)", currentRefStates, indexedRefStates);
   }
 }
diff --git a/java/com/google/gerrit/server/logging/Metadata.java b/java/com/google/gerrit/server/logging/Metadata.java
index 7af204e..d312530 100644
--- a/java/com/google/gerrit/server/logging/Metadata.java
+++ b/java/com/google/gerrit/server/logging/Metadata.java
@@ -59,6 +59,9 @@
   // The type of change ID which the user used to identify a change (e.g. numeric ID, triplet etc.).
   public abstract Optional<String> changeIdType();
 
+  // The cause of an error.
+  public abstract Optional<String> cause();
+
   // The type of an event.
   public abstract Optional<String> eventType();
 
@@ -155,12 +158,12 @@
    * Metadata{accountId=Optional.empty, actionType=Optional.empty, authDomainName=Optional.empty,
    * branchName=Optional.empty, cacheKey=Optional.empty, cacheName=Optional.empty,
    * className=Optional.empty, changeId=Optional[9212550], changeIdType=Optional.empty,
-   * eventType=Optional.empty, exportValue=Optional.empty, filePath=Optional.empty,
-   * garbageCollectorName=Optional.empty, gitOperation=Optional.empty, groupId=Optional.empty,
-   * groupName=Optional.empty, groupUuid=Optional.empty, httpStatus=Optional.empty,
-   * indexName=Optional.empty, indexVersion=Optional[0], methodName=Optional.empty,
-   * multiple=Optional.empty, operationName=Optional.empty, partial=Optional.empty,
-   * noteDbFilePath=Optional.empty, noteDbRefName=Optional.empty,
+   * cause=Optional.empty, eventType=Optional.empty, exportValue=Optional.empty,
+   * filePath=Optional.empty, garbageCollectorName=Optional.empty, gitOperation=Optional.empty,
+   * groupId=Optional.empty, groupName=Optional.empty, groupUuid=Optional.empty,
+   * httpStatus=Optional.empty, indexName=Optional.empty, indexVersion=Optional[0],
+   * methodName=Optional.empty, multiple=Optional.empty, operationName=Optional.empty,
+   * partial=Optional.empty, noteDbFilePath=Optional.empty, noteDbRefName=Optional.empty,
    * noteDbSequenceType=Optional.empty, noteDbTable=Optional.empty, patchSetId=Optional.empty,
    * pluginMetadata=[], pluginName=Optional.empty, projectName=Optional.empty,
    * pushType=Optional.empty, resourceCount=Optional.empty, restViewName=Optional.empty,
@@ -273,6 +276,8 @@
 
     public abstract Builder changeIdType(@Nullable String changeIdType);
 
+    public abstract Builder cause(@Nullable String cause);
+
     public abstract Builder eventType(@Nullable String eventType);
 
     public abstract Builder exportValue(@Nullable String exportValue);
diff --git a/java/com/google/gerrit/server/mail/SignedToken.java b/java/com/google/gerrit/server/mail/SignedToken.java
index 436b854..ba064df 100644
--- a/java/com/google/gerrit/server/mail/SignedToken.java
+++ b/java/com/google/gerrit/server/mail/SignedToken.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.mail;
 
+import com.google.common.io.BaseEncoding;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
@@ -21,7 +22,6 @@
 import javax.crypto.Mac;
 import javax.crypto.ShortBufferException;
 import javax.crypto.spec.SecretKeySpec;
-import org.apache.commons.codec.binary.Base64;
 
 /**
  * Utility function to compute and verify XSRF tokens.
@@ -164,11 +164,11 @@
   }
 
   private static byte[] decodeBase64(final String s) {
-    return Base64.decodeBase64(toBytes(s));
+    return BaseEncoding.base64().decode(s);
   }
 
   private static String encodeBase64(final byte[] buf) {
-    return toString(Base64.encodeBase64(buf));
+    return BaseEncoding.base64().encode(buf);
   }
 
   private static void encodeInt(final byte[] buf, final int o, final int v) {
@@ -202,12 +202,4 @@
     }
     return r;
   }
-
-  private static String toString(final byte[] b) {
-    final StringBuilder r = new StringBuilder(b.length);
-    for (int i = 0; i < b.length; i++) {
-      r.append((char) b[i]);
-    }
-    return r.toString();
-  }
 }
diff --git a/java/com/google/gerrit/server/mail/SignedTokenEmailTokenVerifier.java b/java/com/google/gerrit/server/mail/SignedTokenEmailTokenVerifier.java
index 8b5cc92..8ae06f8 100644
--- a/java/com/google/gerrit/server/mail/SignedTokenEmailTokenVerifier.java
+++ b/java/com/google/gerrit/server/mail/SignedTokenEmailTokenVerifier.java
@@ -17,6 +17,7 @@
 import static com.google.common.base.Preconditions.checkState;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.config.AuthConfig;
 import com.google.gerrit.server.mail.send.RegisterNewEmailSender;
@@ -25,7 +26,6 @@
 import com.google.inject.Singleton;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import org.eclipse.jgit.util.Base64;
 
 /** Verifies the token sent by {@link RegisterNewEmailSender}. */
 @Singleton
@@ -50,7 +50,7 @@
     try {
       String payload = String.format("%s:%s", accountId, emailAddress);
       byte[] utf8 = payload.getBytes(UTF_8);
-      String base64 = Base64.encodeBytes(utf8);
+      String base64 = BaseEncoding.base64().encode(utf8);
       return emailRegistrationToken.newToken(base64);
     } catch (XsrfException e) {
       throw new IllegalArgumentException(e);
@@ -70,7 +70,7 @@
       throw new InvalidTokenException();
     }
 
-    String payload = new String(Base64.decode(token.getData()), UTF_8);
+    String payload = new String(BaseEncoding.base64().decode(token.getData()), UTF_8);
     Matcher matcher = Pattern.compile("^([0-9]+):(.+@.+)$").matcher(payload);
     if (!matcher.matches()) {
       throw new InvalidTokenException();
diff --git a/java/com/google/gerrit/server/mail/send/FromAddressGeneratorProvider.java b/java/com/google/gerrit/server/mail/send/FromAddressGeneratorProvider.java
index bdfe2e8..6a34786 100644
--- a/java/com/google/gerrit/server/mail/send/FromAddressGeneratorProvider.java
+++ b/java/com/google/gerrit/server/mail/send/FromAddressGeneratorProvider.java
@@ -16,6 +16,7 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.common.data.ParameterizedString;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.mail.Address;
@@ -32,7 +33,6 @@
 import java.security.NoSuchAlgorithmException;
 import java.util.Optional;
 import java.util.regex.Pattern;
-import org.apache.commons.codec.binary.Base64;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.PersonIdent;
 
@@ -232,7 +232,7 @@
     try {
       MessageDigest hash = MessageDigest.getInstance("MD5");
       byte[] bytes = hash.digest(data.getBytes(UTF_8));
-      return Base64.encodeBase64URLSafeString(bytes);
+      return BaseEncoding.base64Url().encode(bytes);
     } catch (NoSuchAlgorithmException e) {
       throw new RuntimeException("No MD5 available", e);
     }
diff --git a/java/com/google/gerrit/server/mail/send/OutgoingEmail.java b/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
index e588158..e81f7f4 100644
--- a/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
+++ b/java/com/google/gerrit/server/mail/send/OutgoingEmail.java
@@ -127,11 +127,19 @@
             // this message so they can always review and audit what we sent
             // on their behalf to others.
             //
+            logger.atFine().log(
+                "CC email sender %s because the email strategy of this user is %s",
+                fromUser.get().account().id(), CC_ON_OWN_COMMENTS);
             add(RecipientType.CC, fromId);
           } else if (!notify.accounts().containsValue(fromId) && rcptTo.remove(fromId)) {
             // If they don't want a copy, but we queued one up anyway,
             // drop them from the recipient lists.
             //
+            logger.atFine().log(
+                "Not CCing email sender %s because the email strategy of this user is not %s but %s",
+                fromUser.get().account().id(),
+                CC_ON_OWN_COMMENTS,
+                senderPrefs != null ? senderPrefs.getEmailStrategy() : null);
             removeUser(fromUser.get().account());
           }
         }
@@ -145,8 +153,12 @@
           Account thisUserAccount = thisUser.get().account();
           GeneralPreferencesInfo prefs = thisUser.get().generalPreferences();
           if (prefs == null || prefs.getEmailStrategy() == DISABLED) {
+            logger.atFine().log(
+                "Not emailing account %s because user has set email strategy to %s", id, DISABLED);
             removeUser(thisUserAccount);
           } else if (useHtml() && prefs.getEmailFormat() == EmailFormat.PLAINTEXT) {
+            logger.atFine().log(
+                "Removing account %s from HTML email because user prefers plain text emails", id);
             removeUser(thisUserAccount);
             smtpRcptToPlaintextOnly.add(
                 new Address(thisUserAccount.fullName(), thisUserAccount.preferredEmail()));
@@ -206,12 +218,13 @@
 
       if (!va.smtpRcptTo.isEmpty()) {
         // Send multipart message
-        logger.atFine().log("Sending multipart '%s'", messageClass);
+        logger.atFine().log(
+            "Sending multipart '%s' from %s to %s",
+            messageClass, va.smtpFromAddress, va.smtpRcptTo);
         args.emailSender.send(va.smtpFromAddress, va.smtpRcptTo, va.headers, va.body, va.htmlBody);
       }
 
       if (!smtpRcptToPlaintextOnly.isEmpty()) {
-        logger.atFine().log("Sending plaintext '%s'", messageClass);
         // Send plaintext message
         Map<String, EmailHeader> shallowCopy = new HashMap<>();
         shallowCopy.putAll(headers);
@@ -224,6 +237,9 @@
           to.add(a);
           shallowCopy.put(FieldName.TO, to);
         }
+        logger.atFine().log(
+            "Sending plaintext '%s' from %s to %s",
+            messageClass, va.smtpFromAddress, smtpRcptToPlaintextOnly);
         args.emailSender.send(va.smtpFromAddress, smtpRcptToPlaintextOnly, shallowCopy, va.body);
       }
     }
diff --git a/java/com/google/gerrit/server/notedb/AbstractChangeNotes.java b/java/com/google/gerrit/server/notedb/AbstractChangeNotes.java
index 0acf20e..9a1ba35 100644
--- a/java/com/google/gerrit/server/notedb/AbstractChangeNotes.java
+++ b/java/com/google/gerrit/server/notedb/AbstractChangeNotes.java
@@ -76,6 +76,7 @@
     }
   }
 
+  /** An {@link AutoCloseable} for parsing a single commit into ChangeNotesCommits. */
   public static class LoadHandle implements AutoCloseable {
     private final Repository repo;
     private final ObjectId id;
diff --git a/java/com/google/gerrit/server/notedb/AbstractChangeUpdate.java b/java/com/google/gerrit/server/notedb/AbstractChangeUpdate.java
index ce88f07..d301d34 100644
--- a/java/com/google/gerrit/server/notedb/AbstractChangeUpdate.java
+++ b/java/com/google/gerrit/server/notedb/AbstractChangeUpdate.java
@@ -51,11 +51,11 @@
   private final Change change;
   protected final PersonIdent serverIdent;
 
-  protected PatchSet.Id psId;
+  @Nullable protected PatchSet.Id psId;
   private ObjectId result;
-  protected boolean rootOnly;
+  boolean rootOnly;
 
-  protected AbstractChangeUpdate(
+  AbstractChangeUpdate(
       ChangeNotes notes,
       CurrentUser user,
       PersonIdent serverIdent,
@@ -72,7 +72,7 @@
     this.when = when;
   }
 
-  protected AbstractChangeUpdate(
+  AbstractChangeUpdate(
       ChangeNoteUtil noteUtil,
       PersonIdent serverIdent,
       @Nullable ChangeNotes notes,
@@ -172,7 +172,7 @@
   public abstract boolean isEmpty();
 
   /** Wether this update can only be a root commit. */
-  public boolean isRootOnly() {
+  boolean isRootOnly() {
     return rootOnly;
   }
 
@@ -256,7 +256,7 @@
   protected abstract CommitBuilder applyImpl(RevWalk rw, ObjectInserter ins, ObjectId curr)
       throws IOException;
 
-  protected static final CommitBuilder NO_OP_UPDATE = new CommitBuilder();
+  static final CommitBuilder NO_OP_UPDATE = new CommitBuilder();
 
   ObjectId getResult() {
     return result;
@@ -270,7 +270,7 @@
     return ins.insert(Constants.OBJ_TREE, new byte[] {});
   }
 
-  protected void verifyComment(Comment c) {
+  void verifyComment(Comment c) {
     checkArgument(c.getCommitId() != null, "commit ID required for comment: %s", c);
     checkArgument(
         c.author.getId().equals(getAccountId()),
diff --git a/java/com/google/gerrit/server/notedb/ChangeDraftUpdate.java b/java/com/google/gerrit/server/notedb/ChangeDraftUpdate.java
index b55ce49..72a460c 100644
--- a/java/com/google/gerrit/server/notedb/ChangeDraftUpdate.java
+++ b/java/com/google/gerrit/server/notedb/ChangeDraftUpdate.java
@@ -203,6 +203,7 @@
       cache.get(k.commitId()).deleteComment(k.key());
     }
 
+    // keyed by commit ID.
     Map<ObjectId, RevisionNoteBuilder> builders = cache.getBuilders();
     boolean touchedAnyRevs = false;
     for (Map.Entry<ObjectId, RevisionNoteBuilder> e : builders.entrySet()) {
@@ -233,7 +234,8 @@
       return null;
     }
 
-    cb.setTreeId(rnm.noteMap.writeTree(ins));
+    ObjectId treeId = rnm.noteMap.writeTree(ins);
+    cb.setTreeId(treeId);
     return cb;
   }
 
diff --git a/java/com/google/gerrit/server/notedb/ChangeNotesCommit.java b/java/com/google/gerrit/server/notedb/ChangeNotesCommit.java
index 78f6afc..71cb8c9 100644
--- a/java/com/google/gerrit/server/notedb/ChangeNotesCommit.java
+++ b/java/com/google/gerrit/server/notedb/ChangeNotesCommit.java
@@ -43,6 +43,8 @@
  * </ul>
  */
 public class ChangeNotesCommit extends RevCommit {
+
+  /** A {@link RevWalk} producing {@link ChangeNotesCommit}s. */
   public static ChangeNotesRevWalk newRevWalk(Repository repo) {
     return new ChangeNotesRevWalk(repo);
   }
@@ -62,6 +64,7 @@
     };
   }
 
+  /** A {@link RevWalk} that creates {@link ChangeNotesCommit}s rather than {@link RevCommit}s */
   public static class ChangeNotesRevWalk extends RevWalk {
     private ChangeNotesRevWalk(Repository repo) {
       super(repo);
diff --git a/java/com/google/gerrit/server/notedb/ChangeRevisionNote.java b/java/com/google/gerrit/server/notedb/ChangeRevisionNote.java
index b6443f1..4e52093 100644
--- a/java/com/google/gerrit/server/notedb/ChangeRevisionNote.java
+++ b/java/com/google/gerrit/server/notedb/ChangeRevisionNote.java
@@ -28,6 +28,7 @@
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.util.MutableInteger;
 
+/** Implements the parsing of comment data, handling JSON decoding and push certificates. */
 class ChangeRevisionNote extends RevisionNote<Comment> {
   private final ChangeNoteJson noteJson;
   private final Comment.Status status;
diff --git a/java/com/google/gerrit/server/notedb/ChangeUpdate.java b/java/com/google/gerrit/server/notedb/ChangeUpdate.java
index b2f85fc..02a4dcc 100644
--- a/java/com/google/gerrit/server/notedb/ChangeUpdate.java
+++ b/java/com/google/gerrit/server/notedb/ChangeUpdate.java
@@ -220,8 +220,10 @@
     this.status = status;
   }
 
-  public void fixStatus(Change.Status status) {
-    this.status = status;
+  public void fixStatusToMerged(RequestId submissionId) {
+    checkArgument(submissionId != null, "submission id must be set for merged changes");
+    this.status = Change.Status.MERGED;
+    this.submissionId = submissionId.toStringForStorage();
   }
 
   public void putApproval(String label, short value) {
diff --git a/java/com/google/gerrit/server/notedb/NoteDbUpdateManager.java b/java/com/google/gerrit/server/notedb/NoteDbUpdateManager.java
index 7022cdc..886e02b 100644
--- a/java/com/google/gerrit/server/notedb/NoteDbUpdateManager.java
+++ b/java/com/google/gerrit/server/notedb/NoteDbUpdateManager.java
@@ -78,7 +78,7 @@
   private final ListMultimap<String, ChangeDraftUpdate> draftUpdates;
   private final ListMultimap<String, RobotCommentUpdate> robotCommentUpdates;
   private final ListMultimap<String, NoteDbRewriter> rewriters;
-  private final Set<Change.Id> toDelete;
+  private final Set<Change.Id> changesToDelete;
 
   private OpenRepo changeRepo;
   private OpenRepo allUsersRepo;
@@ -108,7 +108,7 @@
     draftUpdates = MultimapBuilder.hashKeys().arrayListValues().build();
     robotCommentUpdates = MultimapBuilder.hashKeys().arrayListValues().build();
     rewriters = MultimapBuilder.hashKeys().arrayListValues().build();
-    toDelete = new HashSet<>();
+    changesToDelete = new HashSet<>();
   }
 
   @Override
@@ -181,7 +181,7 @@
         && draftUpdates.isEmpty()
         && robotCommentUpdates.isEmpty()
         && rewriters.isEmpty()
-        && toDelete.isEmpty()
+        && changesToDelete.isEmpty()
         && !hasCommands(changeRepo)
         && !hasCommands(allUsersRepo)
         && updateAllUsersAsync.isEmpty();
@@ -258,7 +258,7 @@
 
   public void deleteChange(Change.Id id) {
     checkNotExecuted();
-    toDelete.add(id);
+    changesToDelete.add(id);
   }
 
   /**
@@ -273,7 +273,7 @@
       }
 
       initChangeRepo();
-      if (!draftUpdates.isEmpty() || !toDelete.isEmpty()) {
+      if (!draftUpdates.isEmpty() || !changesToDelete.isEmpty()) {
         initAllUsersRepo();
       }
       addCommands();
@@ -367,7 +367,7 @@
       addRewrites(rewriters, changeRepo);
     }
 
-    for (Change.Id id : toDelete) {
+    for (Change.Id id : changesToDelete) {
       doDelete(id);
     }
   }
diff --git a/java/com/google/gerrit/server/notedb/NoteDbUtil.java b/java/com/google/gerrit/server/notedb/NoteDbUtil.java
index 58a33c8..396e29b 100644
--- a/java/com/google/gerrit/server/notedb/NoteDbUtil.java
+++ b/java/com/google/gerrit/server/notedb/NoteDbUtil.java
@@ -20,7 +20,6 @@
 import com.google.common.primitives.Ints;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.extensions.restapi.RestModifyView;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import java.sql.Timestamp;
 import java.util.Optional;
 import org.eclipse.jgit.lib.PersonIdent;
@@ -34,8 +33,7 @@
   private static final ImmutableList<String> PACKAGE_PREFIXES =
       ImmutableList.of("com.google.gerrit.server.", "com.google.gerrit.");
   private static final ImmutableSet<String> SERVLET_NAMES =
-      ImmutableSet.of(
-          "com.google.gerrit.httpd.restapi.RestApiServlet", RetryingRestModifyView.class.getName());
+      ImmutableSet.of("com.google.gerrit.httpd.restapi.RestApiServlet");
 
   /** Returns an AccountId for the given email address. */
   public static Optional<Account.Id> parseIdent(PersonIdent ident) {
@@ -74,13 +72,16 @@
     StackTraceElement[] trace = Thread.currentThread().getStackTrace();
     int i = findRestApiServlet(trace);
     if (i < 0) {
+      i = findApiImpl(trace);
+    }
+    if (i < 0) {
       return null;
     }
     try {
       for (i--; i >= 0; i--) {
         String cn = trace[i].getClassName();
         Class<?> cls = Class.forName(cn);
-        if (RestModifyView.class.isAssignableFrom(cls) && cls != RetryingRestModifyView.class) {
+        if (RestModifyView.class.isAssignableFrom(cls)) {
           return viewName(cn);
         }
       }
@@ -110,6 +111,16 @@
     return -1;
   }
 
+  private static int findApiImpl(StackTraceElement[] trace) {
+    for (int i = 0; i < trace.length; i++) {
+      String clazz = trace[i].getClassName();
+      if (clazz.startsWith("com.google.gerrit.server.api.") && clazz.endsWith("ApiImpl")) {
+        return i;
+      }
+    }
+    return -1;
+  }
+
   private static String viewName(String cn) {
     String impl = cn.replace('$', '.');
     for (String p : PACKAGE_PREFIXES) {
diff --git a/java/com/google/gerrit/server/notedb/RepoSequence.java b/java/com/google/gerrit/server/notedb/RepoSequence.java
index 8096f89..11ba8cd 100644
--- a/java/com/google/gerrit/server/notedb/RepoSequence.java
+++ b/java/com/google/gerrit/server/notedb/RepoSequence.java
@@ -291,4 +291,48 @@
     ObjectId newId = ins.insert(OBJ_BLOB, Integer.toString(val).getBytes(UTF_8));
     return new ReceiveCommand(ObjectId.zeroId(), newId, RefNames.REFS_SEQUENCES + name);
   }
+
+  public void storeNew(int value) {
+    counterLock.lock();
+    try (Repository repo = repoManager.openRepository(projectName);
+        RevWalk rw = new RevWalk(repo)) {
+      Optional<IntBlob> blob = IntBlob.parse(repo, refName, rw);
+      afterReadRef.run();
+      ObjectId oldId;
+      if (!blob.isPresent()) {
+        oldId = ObjectId.zeroId();
+      } else {
+        oldId = blob.get().id();
+      }
+      RefUpdate refUpdate =
+          IntBlob.tryStore(repo, rw, projectName, refName, oldId, value, gitRefUpdated);
+      RefUpdateUtil.checkResult(refUpdate);
+      counter = value;
+      limit = counter + batchSize;
+      acquireCount++;
+    } catch (IOException e) {
+      throw new StorageException(e);
+    } finally {
+      counterLock.unlock();
+    }
+  }
+
+  public int current() {
+    counterLock.lock();
+    try (Repository repo = repoManager.openRepository(projectName);
+        RevWalk rw = new RevWalk(repo)) {
+      Optional<IntBlob> blob = IntBlob.parse(repo, refName, rw);
+      int current;
+      if (!blob.isPresent()) {
+        current = seed.get();
+      } else {
+        current = blob.get().value();
+      }
+      return current;
+    } catch (IOException e) {
+      throw new StorageException(e);
+    } finally {
+      counterLock.unlock();
+    }
+  }
 }
diff --git a/java/com/google/gerrit/server/notedb/RevisionNote.java b/java/com/google/gerrit/server/notedb/RevisionNote.java
index ff649a9..cd11e1b 100644
--- a/java/com/google/gerrit/server/notedb/RevisionNote.java
+++ b/java/com/google/gerrit/server/notedb/RevisionNote.java
@@ -26,6 +26,10 @@
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.util.MutableInteger;
 
+/**
+ * Data stored in a note, parsed on demand. The data type to parse into is a generic list of type T.
+ * The source of the data is a array of raw bytes
+ */
 @UsedAt(UsedAt.Project.PLUGIN_CHECKS)
 public abstract class RevisionNote<T> {
   static final int MAX_NOTE_SZ = 25 << 20;
@@ -64,6 +68,7 @@
     return entities;
   }
 
+  /** Reads the raw data, and delegates parsing to the {@link #parse(byte[], int)} method. */
   public void parse() throws IOException, ConfigInvalidException {
     raw = reader.open(noteId, OBJ_BLOB).getCachedBytes(MAX_NOTE_SZ);
     MutableInteger p = new MutableInteger();
diff --git a/java/com/google/gerrit/server/notedb/RevisionNoteBuilder.java b/java/com/google/gerrit/server/notedb/RevisionNoteBuilder.java
index e63737c..81273dc 100644
--- a/java/com/google/gerrit/server/notedb/RevisionNoteBuilder.java
+++ b/java/com/google/gerrit/server/notedb/RevisionNoteBuilder.java
@@ -36,6 +36,7 @@
 import org.eclipse.jgit.lib.ObjectId;
 
 class RevisionNoteBuilder {
+  /** Construct a new RevisionNoteMap, seeding it with an existing (immutable) RevisionNoteMap */
   static class Cache {
     private final RevisionNoteMap<? extends RevisionNote<? extends Comment>> revisionNoteMap;
     private final Map<ObjectId, RevisionNoteBuilder> builders;
diff --git a/java/com/google/gerrit/server/notedb/RevisionNoteMap.java b/java/com/google/gerrit/server/notedb/RevisionNoteMap.java
index 3e1bad1..cf16073 100644
--- a/java/com/google/gerrit/server/notedb/RevisionNoteMap.java
+++ b/java/com/google/gerrit/server/notedb/RevisionNoteMap.java
@@ -25,8 +25,16 @@
 import org.eclipse.jgit.notes.Note;
 import org.eclipse.jgit.notes.NoteMap;
 
+/**
+ * A utility class that parses a NoteMap into commit => comment list data.
+ *
+ * @param <T> the RevisionNote for the comment type.
+ */
 class RevisionNoteMap<T extends RevisionNote<? extends Comment>> {
+  // CommitID => blob ID
   final NoteMap noteMap;
+
+  // CommitID => parsed data, immutable map.
   final ImmutableMap<ObjectId, T> revisionNotes;
 
   static RevisionNoteMap<ChangeRevisionNote> parse(
@@ -36,6 +44,7 @@
     for (Note note : noteMap) {
       ChangeRevisionNote rn = new ChangeRevisionNote(noteJson, reader, note.getData(), status);
       rn.parse();
+
       result.put(note.copy(), rn);
     }
     return new RevisionNoteMap<>(noteMap, ImmutableMap.copyOf(result));
diff --git a/java/com/google/gerrit/server/notedb/RobotCommentsRevisionNote.java b/java/com/google/gerrit/server/notedb/RobotCommentsRevisionNote.java
index 97a8ad4..fc4c9fd 100644
--- a/java/com/google/gerrit/server/notedb/RobotCommentsRevisionNote.java
+++ b/java/com/google/gerrit/server/notedb/RobotCommentsRevisionNote.java
@@ -26,6 +26,7 @@
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectReader;
 
+/** Like {@link RevisionNote} but for robot comments. */
 public class RobotCommentsRevisionNote extends RevisionNote<RobotComment> {
   private final ChangeNoteJson noteUtil;
 
diff --git a/java/com/google/gerrit/server/notedb/Sequences.java b/java/com/google/gerrit/server/notedb/Sequences.java
index 73cc600..be68592 100644
--- a/java/com/google/gerrit/server/notedb/Sequences.java
+++ b/java/com/google/gerrit/server/notedb/Sequences.java
@@ -128,4 +128,28 @@
       return groupSeq.next();
     }
   }
+
+  public int currentChangeId() {
+    return changeSeq.current();
+  }
+
+  public int currentAccountId() {
+    return accountSeq.current();
+  }
+
+  public int currentGroupId() {
+    return groupSeq.current();
+  }
+
+  public void setChangeIdValue(int value) {
+    changeSeq.storeNew(value);
+  }
+
+  public void setAccountIdValue(int value) {
+    accountSeq.storeNew(value);
+  }
+
+  public void setGroupIdValue(int value) {
+    groupSeq.storeNew(value);
+  }
 }
diff --git a/java/com/google/gerrit/server/patch/PatchListCacheImpl.java b/java/com/google/gerrit/server/patch/PatchListCacheImpl.java
index 6871652..15fa0f4 100644
--- a/java/com/google/gerrit/server/patch/PatchListCacheImpl.java
+++ b/java/com/google/gerrit/server/patch/PatchListCacheImpl.java
@@ -22,6 +22,7 @@
 import com.google.gerrit.entities.PatchSet;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.client.DiffPreferencesInfo.Whitespace;
+import com.google.gerrit.server.cache.CacheBackend;
 import com.google.gerrit.server.cache.CacheModule;
 import com.google.gerrit.server.config.GerritServerConfig;
 import com.google.inject.Inject;
@@ -45,7 +46,9 @@
       @Override
       protected void configure() {
         factory(PatchListLoader.Factory.class);
-        persist(FILE_NAME, PatchListKey.class, PatchList.class)
+        // TODO(davido): Switch off using legacy cache backend, after fixing PatchListLoader
+        // to be recursion free.
+        persist(FILE_NAME, PatchListKey.class, PatchList.class, CacheBackend.GUAVA)
             .maximumWeight(10 << 20)
             .weigher(PatchListWeigher.class);
 
diff --git a/java/com/google/gerrit/server/patch/PatchScriptBuilder.java b/java/com/google/gerrit/server/patch/PatchScriptBuilder.java
index f3c8eab..0f228fe 100644
--- a/java/com/google/gerrit/server/patch/PatchScriptBuilder.java
+++ b/java/com/google/gerrit/server/patch/PatchScriptBuilder.java
@@ -53,6 +53,7 @@
 import org.eclipse.jgit.treewalk.TreeWalk;
 
 class PatchScriptBuilder {
+
   static final int MAX_CONTEXT = 5000000;
   static final int BIG_FILE = 9000;
 
@@ -66,10 +67,6 @@
   private ComparisonType comparisonType;
   private ObjectId aId;
   private ObjectId bId;
-
-  private final Side a;
-  private final Side b;
-
   private List<Edit> edits;
   private final FileTypeRegistry registry;
   private final PatchListCache patchListCache;
@@ -77,8 +74,6 @@
 
   @Inject
   PatchScriptBuilder(FileTypeRegistry ftr, PatchListCache plc) {
-    a = new Side();
-    b = new Side();
     registry = ftr;
     patchListCache = plc;
   }
@@ -124,11 +119,9 @@
     boolean intralineFailure = false;
     boolean intralineTimeout = false;
 
-    a.path = oldName(content);
-    b.path = newName(content);
-
-    a.resolve(null, aId);
-    b.resolve(a, bId);
+    SideResolver resolver = new SideResolver();
+    Side a = resolver.resolve(oldName(content), null, aId);
+    Side b = resolver.resolve(newName(content), a, bId);
 
     edits = new ArrayList<>(content.getEdits());
     ImmutableSet<Edit> editsDueToRebase = content.getEditsDueToRebase();
@@ -161,7 +154,7 @@
       }
     }
 
-    correctForDifferencesInNewlineAtEnd();
+    correctForDifferencesInNewlineAtEnd(a, b);
 
     if (comments != null) {
       ensureCommentsVisible(comments);
@@ -193,7 +186,7 @@
       //
       context = MAX_CONTEXT;
 
-      packContent(diffPrefs.ignoreWhitespace != Whitespace.IGNORE_NONE);
+      packContent(a, b, diffPrefs.ignoreWhitespace != Whitespace.IGNORE_NONE);
     }
 
     return new PatchScript(
@@ -267,7 +260,7 @@
     }
   }
 
-  private void correctForDifferencesInNewlineAtEnd() {
+  private void correctForDifferencesInNewlineAtEnd(Side a, Side b) {
     // a.src.size() is the size ignoring a newline at the end whereas a.size() considers it.
     int aSize = a.src.size();
     int bSize = b.src.size();
@@ -280,7 +273,7 @@
     }
 
     Optional<Edit> lastEdit = getLast(edits);
-    if (isNewlineAtEndDeleted()) {
+    if (isNewlineAtEndDeleted(a, b)) {
       Optional<Edit> lastLineEdit = lastEdit.filter(edit -> edit.getEndA() == aSize);
       if (lastLineEdit.isPresent()) {
         lastLineEdit.get().extendA();
@@ -288,7 +281,7 @@
         Edit newlineEdit = new Edit(aSize, aSize + 1, bSize, bSize);
         edits.add(newlineEdit);
       }
-    } else if (isNewlineAtEndAdded()) {
+    } else if (isNewlineAtEndAdded(a, b)) {
       Optional<Edit> lastLineEdit = lastEdit.filter(edit -> edit.getEndB() == bSize);
       if (lastLineEdit.isPresent()) {
         lastLineEdit.get().extendB();
@@ -303,11 +296,11 @@
     return list.isEmpty() ? Optional.empty() : Optional.ofNullable(list.get(list.size() - 1));
   }
 
-  private boolean isNewlineAtEndDeleted() {
+  private boolean isNewlineAtEndDeleted(Side a, Side b) {
     return !a.src.isMissingNewlineAtEnd() && b.src.isMissingNewlineAtEnd();
   }
 
-  private boolean isNewlineAtEndAdded() {
+  private boolean isNewlineAtEndAdded(Side a, Side b) {
     return a.src.isMissingNewlineAtEnd() && !b.src.isMissingNewlineAtEnd();
   }
 
@@ -425,7 +418,7 @@
     return last.getEndA() + (b - last.getEndB());
   }
 
-  private void packContent(boolean ignoredWhitespace) {
+  private void packContent(Side a, Side b, boolean ignoredWhitespace) {
     EditList list = new EditList(edits, context, a.size(), b.size());
     for (EditList.Hunk hunk : list.getHunks()) {
       while (hunk.next()) {
@@ -459,16 +452,38 @@
     }
   }
 
-  private class Side {
-    String path;
-    ObjectId id;
-    FileMode mode;
-    byte[] srcContent;
-    Text src;
-    MimeType mimeType = MimeUtil2.UNKNOWN_MIME_TYPE;
-    DisplayMethod displayMethod = DisplayMethod.DIFF;
-    PatchScript.FileMode fileMode = PatchScript.FileMode.FILE;
-    final SparseFileContent dst = new SparseFileContent();
+  private static class Side {
+
+    final String path;
+    final ObjectId id;
+    final FileMode mode;
+    final byte[] srcContent;
+    final Text src;
+    final MimeType mimeType;
+    final DisplayMethod displayMethod;
+    final PatchScript.FileMode fileMode;
+    final SparseFileContent dst;
+
+    public Side(
+        String path,
+        ObjectId id,
+        FileMode mode,
+        byte[] srcContent,
+        Text src,
+        MimeType mimeType,
+        DisplayMethod displayMethod,
+        PatchScript.FileMode fileMode) {
+      this.path = path;
+      this.id = id;
+      this.mode = mode;
+      this.srcContent = srcContent;
+      this.src = src;
+      this.mimeType = mimeType;
+      this.displayMethod = displayMethod;
+      this.fileMode = fileMode;
+      dst = new SparseFileContent();
+      dst.setSize(size());
+    }
 
     int size() {
       if (src == null) {
@@ -488,110 +503,120 @@
     String getSourceLine(int lineNumber) {
       return lineNumber >= src.size() ? "" : src.getString(lineNumber);
     }
+  }
 
-    void resolve(Side other, ObjectId within) throws IOException {
+  private class SideResolver {
+
+    Side resolve(final String path, final Side other, final ObjectId within) throws IOException {
       try {
-        final boolean reuse;
-        if (Patch.COMMIT_MSG.equals(path)) {
+        boolean isCommitMsg = Patch.COMMIT_MSG.equals(path);
+        boolean isMergeList = Patch.MERGE_LIST.equals(path);
+        if (isCommitMsg || isMergeList) {
           if (comparisonType.isAgainstParentOrAutoMerge() && Objects.equals(aId, within)) {
-            id = ObjectId.zeroId();
-            src = Text.EMPTY;
-            srcContent = Text.NO_BYTES;
+            return createSide(
+                path,
+                ObjectId.zeroId(),
+                FileMode.MISSING,
+                Text.NO_BYTES,
+                Text.EMPTY,
+                MimeUtil2.UNKNOWN_MIME_TYPE,
+                DisplayMethod.NONE,
+                false);
+          }
+          Text src =
+              isCommitMsg
+                  ? Text.forCommit(reader, within)
+                  : Text.forMergeList(comparisonType, reader, within);
+          byte[] srcContent = src.getContent();
+          DisplayMethod displayMethod;
+          FileMode mode;
+          if (src == Text.EMPTY) {
             mode = FileMode.MISSING;
             displayMethod = DisplayMethod.NONE;
           } else {
-            id = within;
-            src = Text.forCommit(reader, within);
-            srcContent = src.getContent();
-            if (src == Text.EMPTY) {
-              mode = FileMode.MISSING;
-              displayMethod = DisplayMethod.NONE;
-            } else {
-              mode = FileMode.REGULAR_FILE;
-            }
+            mode = FileMode.REGULAR_FILE;
+            displayMethod = DisplayMethod.DIFF;
           }
-          reuse = false;
-        } else if (Patch.MERGE_LIST.equals(path)) {
-          if (comparisonType.isAgainstParentOrAutoMerge() && Objects.equals(aId, within)) {
-            id = ObjectId.zeroId();
-            src = Text.EMPTY;
-            srcContent = Text.NO_BYTES;
-            mode = FileMode.MISSING;
-            displayMethod = DisplayMethod.NONE;
-          } else {
-            id = within;
-            src = Text.forMergeList(comparisonType, reader, within);
-            srcContent = src.getContent();
-            if (src == Text.EMPTY) {
-              mode = FileMode.MISSING;
-              displayMethod = DisplayMethod.NONE;
-            } else {
-              mode = FileMode.REGULAR_FILE;
-            }
-          }
-          reuse = false;
+          return createSide(
+              path,
+              within,
+              mode,
+              srcContent,
+              src,
+              MimeUtil2.UNKNOWN_MIME_TYPE,
+              displayMethod,
+              false);
+        }
+        final TreeWalk tw = find(path, within);
+        ObjectId id = tw != null ? tw.getObjectId(0) : ObjectId.zeroId();
+        FileMode mode = tw != null ? tw.getFileMode(0) : FileMode.MISSING;
+        boolean reuse =
+            other != null
+                && other.id.equals(id)
+                && (other.mode == mode || isBothFile(other.mode, mode));
+        Text src = null;
+        byte[] srcContent;
+        if (reuse) {
+          srcContent = other.srcContent;
+
+        } else if (mode.getObjectType() == Constants.OBJ_BLOB) {
+          srcContent = Text.asByteArray(db.open(id, Constants.OBJ_BLOB));
+
+        } else if (mode.getObjectType() == Constants.OBJ_COMMIT) {
+          String strContent = "Subproject commit " + ObjectId.toString(id);
+          srcContent = strContent.getBytes(UTF_8);
+
         } else {
-          final TreeWalk tw = find(within);
+          srcContent = Text.NO_BYTES;
+        }
+        MimeType mimeType = MimeUtil2.UNKNOWN_MIME_TYPE;
+        DisplayMethod displayMethod = DisplayMethod.DIFF;
+        if (reuse) {
+          mimeType = other.mimeType;
+          displayMethod = other.displayMethod;
+          src = other.src;
 
-          id = tw != null ? tw.getObjectId(0) : ObjectId.zeroId();
-          mode = tw != null ? tw.getFileMode(0) : FileMode.MISSING;
-          reuse =
-              other != null
-                  && other.id.equals(id)
-                  && (other.mode == mode || isBothFile(other.mode, mode));
-
-          if (reuse) {
-            srcContent = other.srcContent;
-
-          } else if (mode.getObjectType() == Constants.OBJ_BLOB) {
-            srcContent = Text.asByteArray(db.open(id, Constants.OBJ_BLOB));
-
-          } else if (mode.getObjectType() == Constants.OBJ_COMMIT) {
-            String strContent = "Subproject commit " + ObjectId.toString(id);
-            srcContent = strContent.getBytes(UTF_8);
-
-          } else {
-            srcContent = Text.NO_BYTES;
-          }
-
-          if (reuse) {
-            mimeType = other.mimeType;
-            displayMethod = other.displayMethod;
-            src = other.src;
-
-          } else if (srcContent.length > 0 && FileMode.SYMLINK != mode) {
-            mimeType = registry.getMimeType(path, srcContent);
-            if ("image".equals(mimeType.getMediaType()) && registry.isSafeInline(mimeType)) {
-              displayMethod = DisplayMethod.IMG;
-            }
+        } else if (srcContent.length > 0 && FileMode.SYMLINK != mode) {
+          mimeType = registry.getMimeType(path, srcContent);
+          if ("image".equals(mimeType.getMediaType()) && registry.isSafeInline(mimeType)) {
+            displayMethod = DisplayMethod.IMG;
           }
         }
-
-        if (mode == FileMode.MISSING) {
-          displayMethod = DisplayMethod.NONE;
-        }
-
-        if (!reuse) {
-          if (srcContent == Text.NO_BYTES) {
-            src = Text.EMPTY;
-          } else {
-            src = new Text(srcContent);
-          }
-        }
-
-        dst.setSize(size());
-
-        if (mode == FileMode.SYMLINK) {
-          fileMode = PatchScript.FileMode.SYMLINK;
-        } else if (mode == FileMode.GITLINK) {
-          fileMode = PatchScript.FileMode.GITLINK;
-        }
+        return createSide(path, id, mode, srcContent, src, mimeType, displayMethod, reuse);
       } catch (IOException err) {
         throw new IOException("Cannot read " + within.name() + ":" + path, err);
       }
     }
 
-    private TreeWalk find(ObjectId within)
+    private Side createSide(
+        String path,
+        ObjectId id,
+        FileMode mode,
+        byte[] srcContent,
+        Text src,
+        MimeType mimeType,
+        DisplayMethod displayMethod,
+        boolean reuse) {
+      if (!reuse) {
+        if (srcContent == Text.NO_BYTES) {
+          src = Text.EMPTY;
+        } else {
+          src = new Text(srcContent);
+        }
+      }
+      if (mode == FileMode.MISSING) {
+        displayMethod = DisplayMethod.NONE;
+      }
+      PatchScript.FileMode fileMode = PatchScript.FileMode.FILE;
+      if (mode == FileMode.SYMLINK) {
+        fileMode = PatchScript.FileMode.SYMLINK;
+      } else if (mode == FileMode.GITLINK) {
+        fileMode = PatchScript.FileMode.GITLINK;
+      }
+      return new Side(path, id, mode, srcContent, src, mimeType, displayMethod, fileMode);
+    }
+
+    private TreeWalk find(String path, ObjectId within)
         throws MissingObjectException, IncorrectObjectTypeException, CorruptObjectException,
             IOException {
       if (path == null || within == null) {
diff --git a/java/com/google/gerrit/server/permissions/RefControl.java b/java/com/google/gerrit/server/permissions/RefControl.java
index 06fe471..378a512 100644
--- a/java/com/google/gerrit/server/permissions/RefControl.java
+++ b/java/com/google/gerrit/server/permissions/RefControl.java
@@ -440,8 +440,7 @@
     @Override
     public ForChange change(ChangeData cd) {
       try {
-        // TODO(hiesel) Force callers to call database() and use db instead of cd.db()
-        return getProjectControl().controlFor(cd.change()).asForChange(cd);
+        return getProjectControl().controlFor(cd.notes()).asForChange(cd);
       } catch (StorageException e) {
         return FailedPermissionBackend.change("unavailable", e);
       }
diff --git a/java/com/google/gerrit/server/project/LabelDefinitionJson.java b/java/com/google/gerrit/server/project/LabelDefinitionJson.java
new file mode 100644
index 0000000..2ecd8c2
--- /dev/null
+++ b/java/com/google/gerrit/server/project/LabelDefinitionJson.java
@@ -0,0 +1,53 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.project;
+
+import static java.util.stream.Collectors.toMap;
+
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.common.data.LabelValue;
+import com.google.gerrit.entities.Project;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+
+public class LabelDefinitionJson {
+  public static LabelDefinitionInfo format(Project.NameKey projectName, LabelType labelType) {
+    LabelDefinitionInfo label = new LabelDefinitionInfo();
+    label.name = labelType.getName();
+    label.projectName = projectName.get();
+    label.function = labelType.getFunction().getFunctionName();
+    label.values =
+        labelType.getValues().stream().collect(toMap(LabelValue::formatValue, LabelValue::getText));
+    label.defaultValue = labelType.getDefaultValue();
+    label.branches = labelType.getRefPatterns() != null ? labelType.getRefPatterns() : null;
+    label.canOverride = toBoolean(labelType.canOverride());
+    label.copyAnyScore = toBoolean(labelType.isCopyAnyScore());
+    label.copyMinScore = toBoolean(labelType.isCopyMinScore());
+    label.copyMaxScore = toBoolean(labelType.isCopyMaxScore());
+    label.copyAllScoresIfNoChange = toBoolean(labelType.isCopyAllScoresIfNoChange());
+    label.copyAllScoresIfNoCodeChange = toBoolean(labelType.isCopyAllScoresIfNoCodeChange());
+    label.copyAllScoresOnTrivialRebase = toBoolean(labelType.isCopyAllScoresOnTrivialRebase());
+    label.copyAllScoresOnMergeFirstParentUpdate =
+        toBoolean(labelType.isCopyAllScoresOnMergeFirstParentUpdate());
+    label.allowPostSubmit = toBoolean(labelType.allowPostSubmit());
+    label.ignoreSelfApproval = toBoolean(labelType.ignoreSelfApproval());
+    return label;
+  }
+
+  private static Boolean toBoolean(boolean v) {
+    return v ? v : null;
+  }
+
+  private LabelDefinitionJson() {}
+}
diff --git a/java/com/google/gerrit/server/project/LabelResource.java b/java/com/google/gerrit/server/project/LabelResource.java
new file mode 100644
index 0000000..a7a2f07
--- /dev/null
+++ b/java/com/google/gerrit/server/project/LabelResource.java
@@ -0,0 +1,41 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.project;
+
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.restapi.RestResource;
+import com.google.gerrit.extensions.restapi.RestView;
+import com.google.inject.TypeLiteral;
+
+public class LabelResource implements RestResource {
+  public static final TypeLiteral<RestView<LabelResource>> LABEL_KIND =
+      new TypeLiteral<RestView<LabelResource>>() {};
+
+  private final ProjectResource project;
+  private final LabelType labelType;
+
+  public LabelResource(ProjectResource project, LabelType labelType) {
+    this.project = project;
+    this.labelType = labelType;
+  }
+
+  public ProjectResource getProject() {
+    return project;
+  }
+
+  public LabelType getLabelType() {
+    return labelType;
+  }
+}
diff --git a/java/com/google/gerrit/server/project/ProjectConfig.java b/java/com/google/gerrit/server/project/ProjectConfig.java
index 44d9d98..fa877af 100644
--- a/java/com/google/gerrit/server/project/ProjectConfig.java
+++ b/java/com/google/gerrit/server/project/ProjectConfig.java
@@ -19,6 +19,7 @@
 import static com.google.gerrit.common.data.Permission.isPermission;
 import static com.google.gerrit.entities.Project.DEFAULT_SUBMIT_TYPE;
 import static com.google.gerrit.server.permissions.PluginPermissionsUtil.isValidPluginPermission;
+import static java.util.Objects.requireNonNull;
 import static java.util.stream.Collectors.toList;
 
 import com.google.common.base.CharMatcher;
@@ -112,10 +113,10 @@
   public static final String KEY_CAN_OVERRIDE = "canOverride";
   public static final String KEY_BRANCH = "branch";
 
-  private static final String KEY_MATCH = "match";
+  public static final String KEY_MATCH = "match";
   private static final String KEY_HTML = "html";
-  private static final String KEY_LINK = "link";
-  private static final String KEY_ENABLED = "enabled";
+  public static final String KEY_LINK = "link";
+  public static final String KEY_ENABLED = "enabled";
 
   public static final String PROJECT_CONFIG = "project.config";
 
@@ -291,6 +292,11 @@
     commentLinkSections.put(commentLink.name, commentLink);
   }
 
+  public void removeCommentLinkSection(String name) {
+    requireNonNull(name);
+    requireNonNull(commentLinkSections.remove(name));
+  }
+
   private ProjectConfig(Project.NameKey projectName, @Nullable StoredConfig baseConfig) {
     this.projectName = projectName;
     this.baseConfig = baseConfig;
@@ -917,9 +923,18 @@
       lowerNames.put(lower, name);
 
       List<LabelValue> values = new ArrayList<>();
+      Set<Short> allValues = new HashSet<>();
       for (String value : rc.getStringList(LABEL, name, KEY_VALUE)) {
         try {
-          values.add(parseLabelValue(value));
+          LabelValue labelValue = parseLabelValue(value);
+          if (allValues.add(labelValue.getValue())) {
+            values.add(labelValue);
+          } else {
+            error(
+                new ValidationError(
+                    PROJECT_CONFIG,
+                    String.format("Duplicate %s \"%s\" for label \"%s\"", KEY_VALUE, value, name)));
+          }
         } catch (IllegalArgumentException notValue) {
           error(
               new ValidationError(
@@ -1488,6 +1503,8 @@
       List<String> refPatterns = label.getRefPatterns();
       if (refPatterns != null && !refPatterns.isEmpty()) {
         rc.setStringList(LABEL, name, KEY_BRANCH, refPatterns);
+      } else {
+        rc.unset(LABEL, name, KEY_BRANCH);
       }
     }
 
diff --git a/java/com/google/gerrit/server/project/ProjectCreator.java b/java/com/google/gerrit/server/project/ProjectCreator.java
index 2d746d8..04d0859 100644
--- a/java/com/google/gerrit/server/project/ProjectCreator.java
+++ b/java/com/google/gerrit/server/project/ProjectCreator.java
@@ -28,6 +28,7 @@
 import com.google.gerrit.extensions.events.NewProjectCreatedListener;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.GerritPersonIdent;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.account.GroupBackend;
@@ -200,10 +201,11 @@
             referenceUpdated.fire(
                 project, ru, ReceiveCommand.Type.CREATE, identifiedUser.get().state());
             break;
+          case LOCK_FAILURE:
+            throw new LockFailureException(String.format("Failed to create ref \"%s\"", ref), ru);
           case FAST_FORWARD:
           case FORCED:
           case IO_FAILURE:
-          case LOCK_FAILURE:
           case NOT_ATTEMPTED:
           case NO_CHANGE:
           case REJECTED:
diff --git a/java/com/google/gerrit/server/project/Reachable.java b/java/com/google/gerrit/server/project/Reachable.java
index 4ea5d11..6d28646a 100644
--- a/java/com/google/gerrit/server/project/Reachable.java
+++ b/java/com/google/gerrit/server/project/Reachable.java
@@ -17,6 +17,9 @@
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.server.change.IncludedInResolver;
+import com.google.gerrit.server.logging.Metadata;
+import com.google.gerrit.server.logging.TraceContext;
+import com.google.gerrit.server.logging.TraceContext.TraceTimer;
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.permissions.PermissionBackend.RefFilterOptions;
 import com.google.gerrit.server.permissions.PermissionBackendException;
@@ -58,7 +61,15 @@
               .currentUser()
               .project(project)
               .filter(refs, repo, RefFilterOptions.defaults());
-      return IncludedInResolver.includedInAny(repo, rw, commit, filtered.values());
+
+      // The filtering above already produces a voluminous trace. To separate the permission check
+      // from the reachability check, do the trace here:
+      try (TraceTimer timer =
+          TraceContext.newTimer(
+              "IncludedInResolver.includedInAny",
+              Metadata.builder().projectName(project.get()).resourceCount(refs.size()).build())) {
+        return IncludedInResolver.includedInAny(repo, rw, commit, filtered.values());
+      }
     } catch (IOException | PermissionBackendException e) {
       logger.atSevere().withCause(e).log(
           "Cannot verify permissions to commit object %s in repository %s", commit.name(), project);
diff --git a/java/com/google/gerrit/server/query/change/ChangeData.java b/java/com/google/gerrit/server/query/change/ChangeData.java
index c6beac4..78ca0fc 100644
--- a/java/com/google/gerrit/server/query/change/ChangeData.java
+++ b/java/com/google/gerrit/server/query/change/ChangeData.java
@@ -598,7 +598,11 @@
       committer = c.getCommitterIdent();
       parentCount = c.getParentCount();
     } catch (IOException e) {
-      throw new StorageException(e);
+      throw new StorageException(
+          String.format(
+              "Loading commit %s for ps %d of change %d failed.",
+              ps.commitId(), ps.id().get(), ps.id().changeId().get()),
+          e);
     }
     return true;
   }
diff --git a/java/com/google/gerrit/server/query/change/ChangeQueryBuilder.java b/java/com/google/gerrit/server/query/change/ChangeQueryBuilder.java
index d2fc77d..61b90f1 100644
--- a/java/com/google/gerrit/server/query/change/ChangeQueryBuilder.java
+++ b/java/com/google/gerrit/server/query/change/ChangeQueryBuilder.java
@@ -63,6 +63,8 @@
 import com.google.gerrit.server.change.ChangeTriplet;
 import com.google.gerrit.server.config.AllProjectsName;
 import com.google.gerrit.server.config.AllUsersName;
+import com.google.gerrit.server.config.GerritServerConfig;
+import com.google.gerrit.server.config.OperatorAliasConfig;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.index.change.ChangeField;
 import com.google.gerrit.server.index.change.ChangeIndex;
@@ -93,6 +95,7 @@
 import java.util.regex.Pattern;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
+import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.lib.Repository;
 
 /** Parses a query string meant to be applied to change objects. */
@@ -219,6 +222,8 @@
     final SubmitDryRun submitDryRun;
     final GroupMembers groupMembers;
     final Provider<AnonymousUser> anonymousUserProvider;
+    final OperatorAliasConfig operatorAliasConfig;
+    final boolean indexMergeable;
 
     private final Provider<CurrentUser> self;
 
@@ -250,7 +255,9 @@
         StarredChangesUtil starredChangesUtil,
         AccountCache accountCache,
         GroupMembers groupMembers,
-        Provider<AnonymousUser> anonymousUserProvider) {
+        Provider<AnonymousUser> anonymousUserProvider,
+        OperatorAliasConfig operatorAliasConfig,
+        @GerritServerConfig Config gerritConfig) {
       this(
           queryProvider,
           rewriter,
@@ -277,7 +284,9 @@
           starredChangesUtil,
           accountCache,
           groupMembers,
-          anonymousUserProvider);
+          anonymousUserProvider,
+          operatorAliasConfig,
+          gerritConfig.getBoolean("index", "change", "indexMergeable", true));
     }
 
     private Arguments(
@@ -306,7 +315,9 @@
         StarredChangesUtil starredChangesUtil,
         AccountCache accountCache,
         GroupMembers groupMembers,
-        Provider<AnonymousUser> anonymousUserProvider) {
+        Provider<AnonymousUser> anonymousUserProvider,
+        OperatorAliasConfig operatorAliasConfig,
+        boolean indexMergeable) {
       this.queryProvider = queryProvider;
       this.rewriter = rewriter;
       this.opFactories = opFactories;
@@ -333,6 +344,8 @@
       this.hasOperands = hasOperands;
       this.groupMembers = groupMembers;
       this.anonymousUserProvider = anonymousUserProvider;
+      this.operatorAliasConfig = operatorAliasConfig;
+      this.indexMergeable = indexMergeable;
     }
 
     Arguments asUser(CurrentUser otherUser) {
@@ -362,7 +375,9 @@
           starredChangesUtil,
           accountCache,
           groupMembers,
-          anonymousUserProvider);
+          anonymousUserProvider,
+          operatorAliasConfig,
+          indexMergeable);
     }
 
     Arguments asUser(Account.Id otherId) {
@@ -407,6 +422,7 @@
   @Inject
   ChangeQueryBuilder(Arguments args) {
     this(mydef, args);
+    setupAliases();
   }
 
   @VisibleForTesting
@@ -415,6 +431,10 @@
     this.args = args;
   }
 
+  private void setupAliases() {
+    setOperatorAliases(args.operatorAliasConfig.getChangeQueryOperatorAliases());
+  }
+
   public Arguments getArgs() {
     return args;
   }
@@ -558,6 +578,9 @@
     }
 
     if ("mergeable".equalsIgnoreCase(value)) {
+      if (!args.indexMergeable) {
+        throw new QueryParseException("server does not support 'mergeable'. check configs");
+      }
       return new BooleanPredicate(ChangeField.MERGEABLE);
     }
 
@@ -1233,6 +1256,15 @@
     throw new QueryParseException("'revertof' operator is not supported by change index version");
   }
 
+  @Operator
+  public Predicate<ChangeData> submissionId(String value) throws QueryParseException {
+    if (args.getSchema().hasField(ChangeField.SUBMISSIONID)) {
+      return new SubmissionIdPredicate(value);
+    }
+    throw new QueryParseException(
+        "'submissionid' operator is not supported by change index version");
+  }
+
   @Override
   protected Predicate<ChangeData> defaultField(String query) throws QueryParseException {
     if (query.startsWith("refs/")) {
diff --git a/java/com/google/gerrit/server/restapi/BUILD b/java/com/google/gerrit/server/restapi/BUILD
index fd341e9..720e7d2 100644
--- a/java/com/google/gerrit/server/restapi/BUILD
+++ b/java/com/google/gerrit/server/restapi/BUILD
@@ -34,7 +34,6 @@
         "//lib:servlet-api",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:codec",
         "//lib/commons:compress",
         "//lib/commons:lang",
         "//lib/flogger:api",
diff --git a/java/com/google/gerrit/server/restapi/account/PutHttpPassword.java b/java/com/google/gerrit/server/restapi/account/PutHttpPassword.java
index 7b89b9c..36a0c71 100644
--- a/java/com/google/gerrit/server/restapi/account/PutHttpPassword.java
+++ b/java/com/google/gerrit/server/restapi/account/PutHttpPassword.java
@@ -15,9 +15,11 @@
 package com.google.gerrit.server.restapi.account;
 
 import static com.google.gerrit.server.account.externalids.ExternalId.SCHEME_USERNAME;
+import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.common.UsedAt;
 import com.google.gerrit.exceptions.EmailException;
 import com.google.gerrit.extensions.common.HttpPasswordInput;
@@ -43,7 +45,6 @@
 import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
 import java.util.Optional;
-import org.apache.commons.codec.binary.Base64;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 public class PutHttpPassword implements RestModifyView<AccountResource, HttpPasswordInput> {
@@ -142,7 +143,7 @@
     byte[] rand = new byte[LEN];
     rng.nextBytes(rand);
 
-    byte[] enc = Base64.encodeBase64(rand, false);
+    byte[] enc = BaseEncoding.base64().encode(rand).getBytes(UTF_8);
     StringBuilder r = new StringBuilder(enc.length);
     for (int i = 0; i < enc.length; i++) {
       if (enc[i] == '=') {
diff --git a/java/com/google/gerrit/server/restapi/account/PutPreferred.java b/java/com/google/gerrit/server/restapi/account/PutPreferred.java
index 2ddea2f..c781246 100644
--- a/java/com/google/gerrit/server/restapi/account/PutPreferred.java
+++ b/java/com/google/gerrit/server/restapi/account/PutPreferred.java
@@ -145,6 +145,6 @@
     if (exception.get().isPresent()) {
       throw exception.get().get();
     }
-    return alreadyPreferred.get() ? Response.ok("") : Response.created("");
+    return alreadyPreferred.get() ? Response.ok() : Response.created();
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/account/Stars.java b/java/com/google/gerrit/server/restapi/account/Stars.java
index cdaa99d..c27bdd8 100644
--- a/java/com/google/gerrit/server/restapi/account/Stars.java
+++ b/java/com/google/gerrit/server/restapi/account/Stars.java
@@ -98,7 +98,8 @@
 
     @Override
     @SuppressWarnings("unchecked")
-    public Response<List<ChangeInfo>> apply(AccountResource rsrc) throws Exception {
+    public Response<List<ChangeInfo>> apply(AccountResource rsrc)
+        throws RestApiException, PermissionBackendException {
       if (!self.get().hasSameAccountId(rsrc.getUser())) {
         throw new AuthException("not allowed to list stars of another account");
       }
diff --git a/java/com/google/gerrit/server/restapi/change/Abandon.java b/java/com/google/gerrit/server/restapi/change/Abandon.java
index df3b58e..ae69ccd 100644
--- a/java/com/google/gerrit/server/restapi/change/Abandon.java
+++ b/java/com/google/gerrit/server/restapi/change/Abandon.java
@@ -22,6 +22,7 @@
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.PatchSetUtil;
@@ -34,8 +35,6 @@
 import com.google.gerrit.server.permissions.ChangePermission;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -44,10 +43,11 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class Abandon extends RetryingRestModifyView<ChangeResource, AbandonInput, ChangeInfo>
-    implements UiAction<ChangeResource> {
+public class Abandon
+    implements RestModifyView<ChangeResource, AbandonInput>, UiAction<ChangeResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeJson.Factory json;
   private final AbandonOp.Factory abandonOpFactory;
   private final NotifyResolver notifyResolver;
@@ -55,12 +55,12 @@
 
   @Inject
   Abandon(
+      BatchUpdate.Factory updateFactory,
       ChangeJson.Factory json,
-      RetryHelper retryHelper,
       AbandonOp.Factory abandonOpFactory,
       NotifyResolver notifyResolver,
       PatchSetUtil patchSetUtil) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.json = json;
     this.abandonOpFactory = abandonOpFactory;
     this.notifyResolver = notifyResolver;
@@ -68,8 +68,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, AbandonInput input)
+  public Response<ChangeInfo> apply(ChangeResource rsrc, AbandonInput input)
       throws RestApiException, UpdateException, PermissionBackendException, IOException,
           ConfigInvalidException {
     // Not allowed to abandon if the current patch set is locked.
diff --git a/java/com/google/gerrit/server/restapi/change/ApplyFix.java b/java/com/google/gerrit/server/restapi/change/ApplyFix.java
index d31fd92..74c5bc2 100644
--- a/java/com/google/gerrit/server/restapi/change/ApplyFix.java
+++ b/java/com/google/gerrit/server/restapi/change/ApplyFix.java
@@ -18,6 +18,7 @@
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.common.EditInfo;
 import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
@@ -65,8 +66,8 @@
 
   @Override
   public Response<EditInfo> apply(FixResource fixResource, Void nothing)
-      throws AuthException, ResourceConflictException, IOException, ResourceNotFoundException,
-          PermissionBackendException {
+      throws AuthException, BadRequestException, ResourceConflictException, IOException,
+          ResourceNotFoundException, PermissionBackendException {
     RevisionResource revisionResource = fixResource.getRevisionResource();
     Project.NameKey project = revisionResource.getProject();
     ProjectState projectState = projectCache.checkedGet(project);
diff --git a/java/com/google/gerrit/server/restapi/change/ChangeEdits.java b/java/com/google/gerrit/server/restapi/change/ChangeEdits.java
index 6955d8b..1808fa6 100644
--- a/java/com/google/gerrit/server/restapi/change/ChangeEdits.java
+++ b/java/com/google/gerrit/server/restapi/change/ChangeEdits.java
@@ -107,6 +107,7 @@
    * PUT request with a path was called but change edit wasn't created yet. Change edit is created
    * and PUT handler is called.
    */
+  @Singleton
   public static class Create
       implements RestCollectionCreateView<ChangeResource, ChangeEditResource, Put.Input> {
     private final Put putEdit;
@@ -124,6 +125,7 @@
     }
   }
 
+  @Singleton
   public static class DeleteFile
       implements RestCollectionDeleteMissingView<ChangeResource, ChangeEditResource, Input> {
     private final DeleteContent deleteContent;
diff --git a/java/com/google/gerrit/server/restapi/change/CherryPick.java b/java/com/google/gerrit/server/restapi/change/CherryPick.java
index 1a89935..725defc 100644
--- a/java/com/google/gerrit/server/restapi/change/CherryPick.java
+++ b/java/com/google/gerrit/server/restapi/change/CherryPick.java
@@ -25,6 +25,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.change.ChangeJson;
 import com.google.gerrit.server.change.RevisionResource;
@@ -39,8 +40,6 @@
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.submit.IntegrationException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -49,11 +48,11 @@
 
 @Singleton
 public class CherryPick
-    extends RetryingRestModifyView<RevisionResource, CherryPickInput, CherryPickChangeInfo>
-    implements UiAction<RevisionResource> {
+    implements RestModifyView<RevisionResource, CherryPickInput>, UiAction<RevisionResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final CherryPickChange cherryPickChange;
   private final ChangeJson.Factory json;
   private final ContributorAgreementsChecker contributorAgreements;
@@ -62,13 +61,13 @@
   @Inject
   CherryPick(
       PermissionBackend permissionBackend,
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       CherryPickChange cherryPickChange,
       ChangeJson.Factory json,
       ContributorAgreementsChecker contributorAgreements,
       ProjectCache projectCache) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.cherryPickChange = cherryPickChange;
     this.json = json;
     this.contributorAgreements = contributorAgreements;
@@ -76,8 +75,7 @@
   }
 
   @Override
-  public Response<CherryPickChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, RevisionResource rsrc, CherryPickInput input)
+  public Response<CherryPickChangeInfo> apply(RevisionResource rsrc, CherryPickInput input)
       throws IOException, UpdateException, RestApiException, PermissionBackendException,
           ConfigInvalidException, NoSuchProjectException {
     input.parent = input.parent == null ? 1 : input.parent;
diff --git a/java/com/google/gerrit/server/restapi/change/CherryPickCommit.java b/java/com/google/gerrit/server/restapi/change/CherryPickCommit.java
index a3c8a97..729e32d 100644
--- a/java/com/google/gerrit/server/restapi/change/CherryPickCommit.java
+++ b/java/com/google/gerrit/server/restapi/change/CherryPickCommit.java
@@ -24,6 +24,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.change.ChangeJson;
 import com.google.gerrit.server.permissions.PermissionBackend;
@@ -35,8 +36,6 @@
 import com.google.gerrit.server.project.NoSuchProjectException;
 import com.google.gerrit.server.submit.IntegrationException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
@@ -45,9 +44,9 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class CherryPickCommit
-    extends RetryingRestModifyView<CommitResource, CherryPickInput, CherryPickChangeInfo> {
+public class CherryPickCommit implements RestModifyView<CommitResource, CherryPickInput> {
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final Provider<CurrentUser> user;
   private final CherryPickChange cherryPickChange;
   private final ChangeJson.Factory json;
@@ -55,14 +54,14 @@
 
   @Inject
   CherryPickCommit(
-      RetryHelper retryHelper,
+      PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       Provider<CurrentUser> user,
       CherryPickChange cherryPickChange,
       ChangeJson.Factory json,
-      PermissionBackend permissionBackend,
       ContributorAgreementsChecker contributorAgreements) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.user = user;
     this.cherryPickChange = cherryPickChange;
     this.json = json;
@@ -70,8 +69,7 @@
   }
 
   @Override
-  public Response<CherryPickChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, CommitResource rsrc, CherryPickInput input)
+  public Response<CherryPickChangeInfo> apply(CommitResource rsrc, CherryPickInput input)
       throws IOException, UpdateException, RestApiException, PermissionBackendException,
           ConfigInvalidException, NoSuchProjectException {
     String destination = Strings.nullToEmpty(input.destination).trim();
diff --git a/java/com/google/gerrit/server/restapi/change/CreateChange.java b/java/com/google/gerrit/server/restapi/change/CreateChange.java
index acc6465..f4a8b75 100644
--- a/java/com/google/gerrit/server/restapi/change/CreateChange.java
+++ b/java/com/google/gerrit/server/restapi/change/CreateChange.java
@@ -40,6 +40,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestCollectionModifyView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.server.CurrentUser;
@@ -69,8 +70,6 @@
 import com.google.gerrit.server.restapi.project.CommitsCollection;
 import com.google.gerrit.server.restapi.project.ProjectsCollection;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestCollectionModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -103,8 +102,8 @@
 
 @Singleton
 public class CreateChange
-    extends RetryingRestCollectionModifyView<
-        TopLevelResource, ChangeResource, ChangeInput, ChangeInfo> {
+    implements RestCollectionModifyView<TopLevelResource, ChangeResource, ChangeInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final String anonymousCowardName;
   private final GitRepositoryManager gitManager;
   private final Sequences seq;
@@ -126,6 +125,7 @@
 
   @Inject
   CreateChange(
+      BatchUpdate.Factory updateFactory,
       @AnonymousCowardName String anonymousCowardName,
       GitRepositoryManager gitManager,
       Sequences seq,
@@ -138,13 +138,12 @@
       ChangeJson.Factory json,
       ChangeFinder changeFinder,
       Provider<InternalChangeQuery> queryProvider,
-      RetryHelper retryHelper,
       PatchSetUtil psUtil,
       @GerritServerConfig Config config,
       MergeUtil.Factory mergeUtilFactory,
       NotifyResolver notifyResolver,
       ContributorAgreementsChecker contributorAgreements) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.anonymousCowardName = anonymousCowardName;
     this.gitManager = gitManager;
     this.seq = seq;
@@ -166,8 +165,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, TopLevelResource parent, ChangeInput input)
+  public Response<ChangeInfo> apply(TopLevelResource parent, ChangeInput input)
       throws IOException, InvalidChangeOperationException, RestApiException, UpdateException,
           PermissionBackendException, ConfigInvalidException {
     if (!user.get().isIdentifiedUser()) {
diff --git a/java/com/google/gerrit/server/restapi/change/CreateDraftComment.java b/java/com/google/gerrit/server/restapi/change/CreateDraftComment.java
index f434e31..5b7245d 100644
--- a/java/com/google/gerrit/server/restapi/change/CreateDraftComment.java
+++ b/java/com/google/gerrit/server/restapi/change/CreateDraftComment.java
@@ -25,6 +25,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.server.CommentsUtil;
@@ -36,8 +37,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -46,8 +45,8 @@
 import java.util.Collections;
 
 @Singleton
-public class CreateDraftComment
-    extends RetryingRestModifyView<RevisionResource, DraftInput, CommentInfo> {
+public class CreateDraftComment implements RestModifyView<RevisionResource, DraftInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final Provider<CommentJson> commentJson;
   private final CommentsUtil commentsUtil;
   private final PatchSetUtil psUtil;
@@ -55,12 +54,12 @@
 
   @Inject
   CreateDraftComment(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       Provider<CommentJson> commentJson,
       CommentsUtil commentsUtil,
       PatchSetUtil psUtil,
       PatchListCache patchListCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.commentJson = commentJson;
     this.commentsUtil = commentsUtil;
     this.psUtil = psUtil;
@@ -68,8 +67,7 @@
   }
 
   @Override
-  protected Response<CommentInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, RevisionResource rsrc, DraftInput in)
+  public Response<CommentInfo> apply(RevisionResource rsrc, DraftInput in)
       throws RestApiException, UpdateException, PermissionBackendException {
     if (Strings.isNullOrEmpty(in.path)) {
       throw new BadRequestException("path must be non-empty");
diff --git a/java/com/google/gerrit/server/restapi/change/CreateMergePatchSet.java b/java/com/google/gerrit/server/restapi/change/CreateMergePatchSet.java
index b84ac12..8d50b86 100644
--- a/java/com/google/gerrit/server/restapi/change/CreateMergePatchSet.java
+++ b/java/com/google/gerrit/server/restapi/change/CreateMergePatchSet.java
@@ -31,6 +31,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
@@ -53,8 +54,6 @@
 import com.google.gerrit.server.restapi.project.CommitsCollection;
 import com.google.gerrit.server.submit.MergeIdenticalTreeException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -75,8 +74,8 @@
 import org.eclipse.jgit.util.ChangeIdUtil;
 
 @Singleton
-public class CreateMergePatchSet
-    extends RetryingRestModifyView<ChangeResource, MergePatchSetInput, ChangeInfo> {
+public class CreateMergePatchSet implements RestModifyView<ChangeResource, MergePatchSetInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final GitRepositoryManager gitManager;
   private final CommitsCollection commits;
   private final TimeZone serverTimeZone;
@@ -91,6 +90,7 @@
 
   @Inject
   CreateMergePatchSet(
+      BatchUpdate.Factory updateFactory,
       GitRepositoryManager gitManager,
       CommitsCollection commits,
       @GerritPersonIdent PersonIdent myIdent,
@@ -98,12 +98,11 @@
       ChangeJson.Factory json,
       PatchSetUtil psUtil,
       MergeUtil.Factory mergeUtilFactory,
-      RetryHelper retryHelper,
       PatchSetInserter.Factory patchSetInserterFactory,
       ProjectCache projectCache,
       ChangeFinder changeFinder,
       PermissionBackend permissionBackend) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.gitManager = gitManager;
     this.commits = commits;
     this.serverTimeZone = myIdent.getTimeZone();
@@ -118,8 +117,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, MergePatchSetInput in)
+  public Response<ChangeInfo> apply(ChangeResource rsrc, MergePatchSetInput in)
       throws IOException, RestApiException, UpdateException, PermissionBackendException {
     // Not allowed to create a new patch set if the current patch set is locked.
     psUtil.checkPatchSetNotLocked(rsrc.getNotes());
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteAssignee.java b/java/com/google/gerrit/server/restapi/change/DeleteAssignee.java
index 834782f..20fd675 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteAssignee.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteAssignee.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.extensions.common.Input;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.account.AccountLoader;
@@ -34,16 +35,14 @@
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class DeleteAssignee extends RetryingRestModifyView<ChangeResource, Input, AccountInfo> {
-
+public class DeleteAssignee implements RestModifyView<ChangeResource, Input> {
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeMessagesUtil cmUtil;
   private final AssigneeChanged assigneeChanged;
   private final IdentifiedUser.GenericFactory userFactory;
@@ -51,12 +50,12 @@
 
   @Inject
   DeleteAssignee(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       ChangeMessagesUtil cmUtil,
       AssigneeChanged assigneeChanged,
       IdentifiedUser.GenericFactory userFactory,
       AccountLoader.Factory accountLoaderFactory) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.cmUtil = cmUtil;
     this.assigneeChanged = assigneeChanged;
     this.userFactory = userFactory;
@@ -64,8 +63,7 @@
   }
 
   @Override
-  protected Response<AccountInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input input)
+  public Response<AccountInfo> apply(ChangeResource rsrc, Input input)
       throws RestApiException, UpdateException, PermissionBackendException {
     rsrc.permissions().check(ChangePermission.EDIT_ASSIGNEE);
 
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteChange.java b/java/com/google/gerrit/server/restapi/change/DeleteChange.java
index aa4dcf0..3ca5463 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteChange.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteChange.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.extensions.restapi.MethodNotAllowedException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.DeleteChangeOp;
@@ -28,28 +29,25 @@
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class DeleteChange extends RetryingRestModifyView<ChangeResource, Input, Object>
-    implements UiAction<ChangeResource> {
-
+public class DeleteChange
+    implements RestModifyView<ChangeResource, Input>, UiAction<ChangeResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final DeleteChangeOp.Factory opFactory;
 
   @Inject
-  public DeleteChange(RetryHelper retryHelper, DeleteChangeOp.Factory opFactory) {
-    super(retryHelper);
+  public DeleteChange(BatchUpdate.Factory updateFactory, DeleteChangeOp.Factory opFactory) {
+    this.updateFactory = updateFactory;
     this.opFactory = opFactory;
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input input)
+  public Response<Object> apply(ChangeResource rsrc, Input input)
       throws RestApiException, UpdateException, PermissionBackendException {
     if (!isChangeDeletable(rsrc)) {
       throw new MethodNotAllowedException("delete not permitted");
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteChangeMessage.java b/java/com/google/gerrit/server/restapi/change/DeleteChangeMessage.java
index 30cfad6..f79209d 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteChangeMessage.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteChangeMessage.java
@@ -28,6 +28,7 @@
 import com.google.gerrit.extensions.common.Input;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.account.AccountLoader;
@@ -39,8 +40,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -52,11 +51,11 @@
 /** Deletes a change message by rewriting history. */
 @Singleton
 public class DeleteChangeMessage
-    extends RetryingRestModifyView<
-        ChangeMessageResource, DeleteChangeMessageInput, ChangeMessageInfo> {
+    implements RestModifyView<ChangeMessageResource, DeleteChangeMessageInput> {
 
   private final Provider<CurrentUser> userProvider;
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeMessagesUtil changeMessagesUtil;
   private final AccountLoader.Factory accountLoaderFactory;
   private final ChangeNotes.Factory notesFactory;
@@ -65,23 +64,21 @@
   public DeleteChangeMessage(
       Provider<CurrentUser> userProvider,
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       ChangeMessagesUtil changeMessagesUtil,
       AccountLoader.Factory accountLoaderFactory,
-      ChangeNotes.Factory notesFactory,
-      RetryHelper retryHelper) {
-    super(retryHelper);
+      ChangeNotes.Factory notesFactory) {
     this.userProvider = userProvider;
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.changeMessagesUtil = changeMessagesUtil;
     this.accountLoaderFactory = accountLoaderFactory;
     this.notesFactory = notesFactory;
   }
 
   @Override
-  public Response<ChangeMessageInfo> applyImpl(
-      BatchUpdate.Factory updateFactory,
-      ChangeMessageResource resource,
-      DeleteChangeMessageInput input)
+  public Response<ChangeMessageInfo> apply(
+      ChangeMessageResource resource, DeleteChangeMessageInput input)
       throws RestApiException, PermissionBackendException, UpdateException, IOException {
     CurrentUser user = userProvider.get();
     permissionBackend.user(user).check(GlobalPermission.ADMINISTRATE_SERVER);
@@ -146,21 +143,18 @@
 
   @Singleton
   public static class DefaultDeleteChangeMessage
-      extends RetryingRestModifyView<ChangeMessageResource, Input, ChangeMessageInfo> {
+      implements RestModifyView<ChangeMessageResource, Input> {
     private final DeleteChangeMessage deleteChangeMessage;
 
     @Inject
-    public DefaultDeleteChangeMessage(
-        DeleteChangeMessage deleteChangeMessage, RetryHelper retryHelper) {
-      super(retryHelper);
+    public DefaultDeleteChangeMessage(DeleteChangeMessage deleteChangeMessage) {
       this.deleteChangeMessage = deleteChangeMessage;
     }
 
     @Override
-    protected Response<ChangeMessageInfo> applyImpl(
-        BatchUpdate.Factory updateFactory, ChangeMessageResource resource, Input input)
-        throws Exception {
-      return deleteChangeMessage.applyImpl(updateFactory, resource, new DeleteChangeMessageInput());
+    public Response<ChangeMessageInfo> apply(ChangeMessageResource resource, Input input)
+        throws RestApiException, PermissionBackendException, UpdateException, IOException {
+      return deleteChangeMessage.apply(resource, new DeleteChangeMessageInput());
     }
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteComment.java b/java/com/google/gerrit/server/restapi/change/DeleteComment.java
index 95479a6..f915728 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteComment.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteComment.java
@@ -23,6 +23,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.CommentsUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.change.CommentResource;
@@ -33,8 +34,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -46,11 +45,11 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class DeleteComment
-    extends RetryingRestModifyView<CommentResource, DeleteCommentInput, CommentInfo> {
+public class DeleteComment implements RestModifyView<CommentResource, DeleteCommentInput> {
 
   private final Provider<CurrentUser> userProvider;
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final CommentsUtil commentsUtil;
   private final Provider<CommentJson> commentJson;
   private final ChangeNotes.Factory notesFactory;
@@ -59,21 +58,20 @@
   public DeleteComment(
       Provider<CurrentUser> userProvider,
       PermissionBackend permissionBackend,
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       CommentsUtil commentsUtil,
       Provider<CommentJson> commentJson,
       ChangeNotes.Factory notesFactory) {
-    super(retryHelper);
     this.userProvider = userProvider;
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.commentsUtil = commentsUtil;
     this.commentJson = commentJson;
     this.notesFactory = notesFactory;
   }
 
   @Override
-  public Response<CommentInfo> applyImpl(
-      BatchUpdate.Factory batchUpdateFactory, CommentResource rsrc, DeleteCommentInput input)
+  public Response<CommentInfo> apply(CommentResource rsrc, DeleteCommentInput input)
       throws RestApiException, IOException, ConfigInvalidException, PermissionBackendException,
           UpdateException {
     CurrentUser user = userProvider.get();
@@ -86,8 +84,7 @@
     String newMessage = getCommentNewMessage(user.asIdentifiedUser().getName(), input.reason);
     DeleteCommentOp deleteCommentOp = new DeleteCommentOp(rsrc, newMessage);
     try (BatchUpdate batchUpdate =
-        batchUpdateFactory.create(
-            rsrc.getRevisionResource().getProject(), user, TimeUtil.nowTs())) {
+        updateFactory.create(rsrc.getRevisionResource().getProject(), user, TimeUtil.nowTs())) {
       batchUpdate.addOp(rsrc.getRevisionResource().getChange().getId(), deleteCommentOp).execute();
     }
 
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteDraftComment.java b/java/com/google/gerrit/server/restapi/change/DeleteDraftComment.java
index 9296988..89fc3b7 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteDraftComment.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteDraftComment.java
@@ -23,6 +23,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.CommentsUtil;
 import com.google.gerrit.server.PatchSetUtil;
 import com.google.gerrit.server.change.DraftCommentResource;
@@ -31,8 +32,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -41,28 +40,26 @@
 import java.util.Optional;
 
 @Singleton
-public class DeleteDraftComment
-    extends RetryingRestModifyView<DraftCommentResource, Input, CommentInfo> {
-
+public class DeleteDraftComment implements RestModifyView<DraftCommentResource, Input> {
+  private final BatchUpdate.Factory updateFactory;
   private final CommentsUtil commentsUtil;
   private final PatchSetUtil psUtil;
   private final PatchListCache patchListCache;
 
   @Inject
   DeleteDraftComment(
+      BatchUpdate.Factory updateFactory,
       CommentsUtil commentsUtil,
       PatchSetUtil psUtil,
-      RetryHelper retryHelper,
       PatchListCache patchListCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.commentsUtil = commentsUtil;
     this.psUtil = psUtil;
     this.patchListCache = patchListCache;
   }
 
   @Override
-  protected Response<CommentInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, DraftCommentResource rsrc, Input input)
+  public Response<CommentInfo> apply(DraftCommentResource rsrc, Input input)
       throws RestApiException, UpdateException {
     try (BatchUpdate bu =
         updateFactory.create(rsrc.getChange().getProject(), rsrc.getUser(), TimeUtil.nowTs())) {
diff --git a/java/com/google/gerrit/server/restapi/change/DeletePrivate.java b/java/com/google/gerrit/server/restapi/change/DeletePrivate.java
index de7a683..16b7136 100644
--- a/java/com/google/gerrit/server/restapi/change/DeletePrivate.java
+++ b/java/com/google/gerrit/server/restapi/change/DeletePrivate.java
@@ -17,42 +17,41 @@
 import static com.google.gerrit.extensions.conditions.BooleanCondition.or;
 
 import com.google.gerrit.common.Nullable;
+import com.google.gerrit.extensions.common.InputWithMessage;
 import com.google.gerrit.extensions.conditions.BooleanCondition;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.SetPrivateOp;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class DeletePrivate
-    extends RetryingRestModifyView<ChangeResource, SetPrivateOp.Input, String> {
+public class DeletePrivate implements RestModifyView<ChangeResource, InputWithMessage> {
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final SetPrivateOp.Factory setPrivateOpFactory;
 
   @Inject
   DeletePrivate(
-      RetryHelper retryHelper,
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       SetPrivateOp.Factory setPrivateOpFactory) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.setPrivateOpFactory = setPrivateOpFactory;
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, @Nullable SetPrivateOp.Input input)
+  public Response<String> apply(ChangeResource rsrc, @Nullable InputWithMessage input)
       throws RestApiException, UpdateException {
     if (!canDeletePrivate(rsrc).value()) {
       throw new AuthException("not allowed to unmark private");
diff --git a/java/com/google/gerrit/server/restapi/change/DeletePrivateByPost.java b/java/com/google/gerrit/server/restapi/change/DeletePrivateByPost.java
index c86d0ca..10feb63 100644
--- a/java/com/google/gerrit/server/restapi/change/DeletePrivateByPost.java
+++ b/java/com/google/gerrit/server/restapi/change/DeletePrivateByPost.java
@@ -20,7 +20,7 @@
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.SetPrivateOp;
 import com.google.gerrit.server.permissions.PermissionBackend;
-import com.google.gerrit.server.update.RetryHelper;
+import com.google.gerrit.server.update.BatchUpdate;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
@@ -28,10 +28,10 @@
 public class DeletePrivateByPost extends DeletePrivate implements UiAction<ChangeResource> {
   @Inject
   DeletePrivateByPost(
-      RetryHelper retryHelper,
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       SetPrivateOp.Factory setPrivateOpFactory) {
-    super(retryHelper, permissionBackend, setPrivateOpFactory);
+    super(permissionBackend, updateFactory, setPrivateOpFactory);
   }
 
   @Override
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteReviewer.java b/java/com/google/gerrit/server/restapi/change/DeleteReviewer.java
index b98bb3b..3e4a483 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteReviewer.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteReviewer.java
@@ -19,39 +19,36 @@
 import com.google.gerrit.extensions.api.changes.NotifyHandling;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.change.DeleteReviewerByEmailOp;
 import com.google.gerrit.server.change.DeleteReviewerOp;
 import com.google.gerrit.server.change.NotifyResolver;
 import com.google.gerrit.server.change.ReviewerResource;
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class DeleteReviewer
-    extends RetryingRestModifyView<ReviewerResource, DeleteReviewerInput, Object> {
-
+public class DeleteReviewer implements RestModifyView<ReviewerResource, DeleteReviewerInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final DeleteReviewerOp.Factory deleteReviewerOpFactory;
   private final DeleteReviewerByEmailOp.Factory deleteReviewerByEmailOpFactory;
 
   @Inject
   DeleteReviewer(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       DeleteReviewerOp.Factory deleteReviewerOpFactory,
       DeleteReviewerByEmailOp.Factory deleteReviewerByEmailOpFactory) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.deleteReviewerOpFactory = deleteReviewerOpFactory;
     this.deleteReviewerByEmailOpFactory = deleteReviewerByEmailOpFactory;
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, ReviewerResource rsrc, DeleteReviewerInput input)
+  public Response<Object> apply(ReviewerResource rsrc, DeleteReviewerInput input)
       throws RestApiException, UpdateException {
     if (input == null) {
       input = new DeleteReviewerInput();
diff --git a/java/com/google/gerrit/server/restapi/change/DeleteVote.java b/java/com/google/gerrit/server/restapi/change/DeleteVote.java
index 1193ad6..bdbf3f7 100644
--- a/java/com/google/gerrit/server/restapi/change/DeleteVote.java
+++ b/java/com/google/gerrit/server/restapi/change/DeleteVote.java
@@ -32,6 +32,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.IdentifiedUser;
@@ -51,8 +52,6 @@
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.LabelVote;
 import com.google.gerrit.server.util.time.TimeUtil;
@@ -64,9 +63,10 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class DeleteVote extends RetryingRestModifyView<VoteResource, DeleteVoteInput, Object> {
+public class DeleteVote implements RestModifyView<VoteResource, DeleteVoteInput> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
+  private final BatchUpdate.Factory updateFactory;
   private final ApprovalsUtil approvalsUtil;
   private final PatchSetUtil psUtil;
   private final ChangeMessagesUtil cmUtil;
@@ -79,7 +79,7 @@
 
   @Inject
   DeleteVote(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       ApprovalsUtil approvalsUtil,
       PatchSetUtil psUtil,
       ChangeMessagesUtil cmUtil,
@@ -89,7 +89,7 @@
       NotifyResolver notifyResolver,
       RemoveReviewerControl removeReviewerControl,
       ProjectCache projectCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.approvalsUtil = approvalsUtil;
     this.psUtil = psUtil;
     this.cmUtil = cmUtil;
@@ -102,8 +102,7 @@
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, VoteResource rsrc, DeleteVoteInput input)
+  public Response<Object> apply(VoteResource rsrc, DeleteVoteInput input)
       throws RestApiException, UpdateException, IOException, ConfigInvalidException {
     if (input == null) {
       input = new DeleteVoteInput();
diff --git a/java/com/google/gerrit/server/restapi/change/GetDiff.java b/java/com/google/gerrit/server/restapi/change/GetDiff.java
index 857205a..a6536ce 100644
--- a/java/com/google/gerrit/server/restapi/change/GetDiff.java
+++ b/java/com/google/gerrit/server/restapi/change/GetDiff.java
@@ -22,6 +22,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
+import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.common.data.PatchScript;
 import com.google.gerrit.common.data.PatchScript.DisplayMethod;
 import com.google.gerrit.entities.Patch;
@@ -73,6 +74,8 @@
 import org.kohsuke.args4j.spi.Setter;
 
 public class GetDiff implements RestReadView<FileResource> {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
   private static final ImmutableMap<Patch.ChangeType, ChangeType> CHANGE_TYPE =
       Maps.immutableEnumMap(
           new ImmutableMap.Builder<Patch.ChangeType, ChangeType>()
@@ -134,11 +137,17 @@
     }
     prefs.context = context;
     prefs.intralineDifference = intraline;
+    logger.atFine().log(
+        "diff preferences: ignoreWhitespace = %s, context = %s, intralineDifference = %s",
+        prefs.ignoreWhitespace, prefs.context, prefs.intralineDifference);
 
     PatchScriptFactory psf;
     PatchSet basePatchSet = null;
     PatchSet.Id pId = resource.getPatchKey().patchSetId();
     String fileName = resource.getPatchKey().fileName();
+    logger.atFine().log(
+        "patchSetId = %d, fileName = %s, base = %s, parentNum = %d",
+        pId.get(), fileName, base, parentNum);
     ChangeNotes notes = resource.getRevision().getNotes();
     if (base != null) {
       RevisionResource baseResource =
@@ -155,23 +164,26 @@
       psf.setLoadHistory(false);
       psf.setLoadComments(context != DiffPreferencesInfo.WHOLE_FILE_CONTEXT);
       PatchScript ps = psf.call();
-      Content content = new Content(ps);
+      ContentCollector contentCollector = new ContentCollector(ps);
       Set<Edit> editsDueToRebase = ps.getEditsDueToRebase();
       for (Edit edit : ps.getEdits()) {
+        logger.atFine().log("next edit = %s", edit);
+
         if (edit.getType() == Edit.Type.EMPTY) {
+          logger.atFine().log("skip empty edit");
           continue;
         }
-        content.addCommon(edit.getBeginA());
+        contentCollector.addCommon(edit.getBeginA());
 
         checkState(
-            content.nextA == edit.getBeginA(),
+            contentCollector.nextA == edit.getBeginA(),
             "nextA = %s; want %s",
-            content.nextA,
+            contentCollector.nextA,
             edit.getBeginA());
         checkState(
-            content.nextB == edit.getBeginB(),
+            contentCollector.nextB == edit.getBeginB(),
             "nextB = %s; want %s",
-            content.nextB,
+            contentCollector.nextB,
             edit.getBeginB());
         switch (edit.getType()) {
           case DELETE:
@@ -180,23 +192,24 @@
             List<Edit> internalEdit =
                 edit instanceof ReplaceEdit ? ((ReplaceEdit) edit).getInternalEdits() : null;
             boolean dueToRebase = editsDueToRebase.contains(edit);
-            content.addDiff(edit.getEndA(), edit.getEndB(), internalEdit, dueToRebase);
+            contentCollector.addDiff(edit.getEndA(), edit.getEndB(), internalEdit, dueToRebase);
             break;
           case EMPTY:
           default:
             throw new IllegalStateException();
         }
       }
-      content.addCommon(ps.getA().size());
+      contentCollector.addCommon(ps.getA().size());
 
       ProjectState state = projectCache.get(resource.getRevision().getChange().getProject());
 
       DiffInfo result = new DiffInfo();
-      String revA = basePatchSet != null ? basePatchSet.refName() : content.commitIdA;
+      String revA = basePatchSet != null ? basePatchSet.refName() : ps.getFileInfoA().commitId;
       String revB =
           resource.getRevision().getEdit().isPresent()
               ? resource.getRevision().getEdit().get().getRefName()
               : resource.getRevision().getPatchSet().refName();
+      logger.atFine().log("revA = %s, revB = %s", revA, revB);
 
       ImmutableList<DiffWebLinkInfo> links =
           webLinks.getDiffLinks(
@@ -221,7 +234,7 @@
                 state, result.metaA.name, ps.getFileModeA(), ps.getMimeTypeA());
         result.metaA.lines = ps.getA().size();
         result.metaA.webLinks = getFileWebLinks(state.getProject(), revA, result.metaA.name);
-        result.metaA.commitId = content.commitIdA;
+        result.metaA.commitId = ps.getFileInfoA().commitId;
       }
 
       if (ps.getDisplayMethodB() != DisplayMethod.NONE) {
@@ -232,7 +245,7 @@
                 state, result.metaB.name, ps.getFileModeB(), ps.getMimeTypeB());
         result.metaB.lines = ps.getB().size();
         result.metaB.webLinks = getFileWebLinks(state.getProject(), revB, result.metaB.name);
-        result.metaB.commitId = content.commitIdB;
+        result.metaB.commitId = ps.getFileInfoB().commitId;
       }
 
       if (intraline) {
@@ -243,9 +256,11 @@
         } else {
           result.intralineStatus = IntraLineStatus.OK;
         }
+        logger.atFine().log("intralineStatus = %s", result.intralineStatus);
       }
 
       result.changeType = CHANGE_TYPE.get(ps.getChangeType());
+      logger.atFine().log("changeType = %s", result.changeType);
       if (result.changeType == null) {
         throw new IllegalStateException("unknown change type: " + ps.getChangeType());
       }
@@ -253,7 +268,7 @@
       if (ps.getPatchHeader().size() > 0) {
         result.diffHeader = ps.getPatchHeader();
       }
-      result.content = content.lines;
+      result.content = contentCollector.lines;
 
       Response<DiffInfo> r = Response.ok(result);
       if (resource.isCacheable()) {
@@ -297,39 +312,46 @@
     return this;
   }
 
-  private static class Content {
+  private static class ContentCollector {
     final List<ContentEntry> lines;
     final SparseFileContent fileA;
     final SparseFileContent fileB;
     final boolean ignoreWS;
-    final String commitIdA;
-    final String commitIdB;
 
     int nextA;
     int nextB;
 
-    Content(PatchScript ps) {
+    ContentCollector(PatchScript ps) {
       lines = Lists.newArrayListWithExpectedSize(ps.getEdits().size() + 2);
       fileA = ps.getA();
       fileB = ps.getB();
       ignoreWS = ps.isIgnoreWhitespace();
-      commitIdA = ps.getCommitIdA();
-      commitIdB = ps.getCommitIdB();
     }
 
     void addCommon(int end) {
+      logger.atFine().log("addCommon: end = %d", end);
+
       end = Math.min(end, fileA.size());
+      logger.atFine().log("end = %d", end);
+
       if (nextA >= end) {
+        logger.atFine().log("nextA >= end: nextA = %d, end = %d", nextA, end);
         return;
       }
 
       while (nextA < end) {
+        logger.atFine().log("nextA < end: nextA = %d, end = %d", nextA, end);
+
         if (!fileA.contains(nextA)) {
+          logger.atFine().log("fileA does not contain nextA: nextA = %d", nextA);
+
           int endRegion = Math.min(end, nextA == 0 ? fileA.first() : fileA.next(nextA - 1));
           int len = endRegion - nextA;
           entry().skip = len;
           nextA = endRegion;
           nextB += len;
+
+          logger.atFine().log("setting: nextA = %d, nextB = %d", nextA, nextB);
           continue;
         }
 
@@ -337,6 +359,7 @@
         for (int i = nextA; i == nextA && i < end; i = fileA.next(i), nextA++, nextB++) {
           if (ignoreWS && fileB.contains(nextB)) {
             if (e == null || e.common == null) {
+              logger.atFine().log("create new common entry: nextA = %d, nextB = %d", nextA, nextB);
               e = entry();
               e.a = Lists.newArrayListWithCapacity(end - nextA);
               e.b = Lists.newArrayListWithCapacity(end - nextA);
@@ -346,48 +369,71 @@
             e.b.add(fileB.get(nextB));
           } else {
             if (e == null || e.common != null) {
+              logger.atFine().log(
+                  "create new non-common entry: nextA = %d, nextB = %d", nextA, nextB);
               e = entry();
               e.ab = Lists.newArrayListWithCapacity(end - nextA);
             }
             e.ab.add(fileA.get(nextA));
           }
         }
+        logger.atFine().log("nextA = %d, nextB = %d", nextA, nextB);
       }
     }
 
     void addDiff(int endA, int endB, List<Edit> internalEdit, boolean dueToRebase) {
+      logger.atFine().log(
+          "addDiff: endA = %d, endB = %d, numberOfInternalEdits = %d, dueToRebase = %s",
+          endA, endB, internalEdit != null ? internalEdit.size() : 0, dueToRebase);
+
       int lenA = endA - nextA;
       int lenB = endB - nextB;
+      logger.atFine().log("lenA = %d, lenB = %d", lenA, lenB);
       checkState(lenA > 0 || lenB > 0);
 
+      logger.atFine().log("create non-common entry");
       ContentEntry e = entry();
       if (lenA > 0) {
+        logger.atFine().log("lenA > 0: lenA = %d", lenA);
         e.a = Lists.newArrayListWithCapacity(lenA);
         for (; nextA < endA; nextA++) {
           e.a.add(fileA.get(nextA));
         }
       }
       if (lenB > 0) {
+        logger.atFine().log("lenB > 0: lenB = %d", lenB);
         e.b = Lists.newArrayListWithCapacity(lenB);
         for (; nextB < endB; nextB++) {
           e.b.add(fileB.get(nextB));
         }
       }
       if (internalEdit != null && !internalEdit.isEmpty()) {
+        logger.atFine().log("processing internal edits");
+
         e.editA = Lists.newArrayListWithCapacity(internalEdit.size() * 2);
         e.editB = Lists.newArrayListWithCapacity(internalEdit.size() * 2);
         int lastA = 0;
         int lastB = 0;
         for (Edit edit : internalEdit) {
+          logger.atFine().log("internal edit = %s", edit);
+
           if (edit.getBeginA() != edit.getEndA()) {
+            logger.atFine().log(
+                "edit.getBeginA() != edit.getEndA(): edit.getBeginA() = %d, edit.getEndA() = %d",
+                edit.getBeginA(), edit.getEndA());
             e.editA.add(
                 ImmutableList.of(edit.getBeginA() - lastA, edit.getEndA() - edit.getBeginA()));
             lastA = edit.getEndA();
+            logger.atFine().log("lastA = %d", lastA);
           }
           if (edit.getBeginB() != edit.getEndB()) {
+            logger.atFine().log(
+                "edit.getBeginB() != edit.getEndB(): edit.getBeginB() = %d, edit.getEndB() = %d",
+                edit.getBeginB(), edit.getEndB());
             e.editB.add(
                 ImmutableList.of(edit.getBeginB() - lastB, edit.getEndB() - edit.getBeginB()));
             lastB = edit.getEndB();
+            logger.atFine().log("lastB = %d", lastB);
           }
         }
       }
diff --git a/java/com/google/gerrit/server/restapi/change/Ignore.java b/java/com/google/gerrit/server/restapi/change/Ignore.java
index 25cf311..a049e54 100644
--- a/java/com/google/gerrit/server/restapi/change/Ignore.java
+++ b/java/com/google/gerrit/server/restapi/change/Ignore.java
@@ -60,7 +60,7 @@
       if (!isIgnored(rsrc)) {
         stars.ignore(rsrc);
       }
-      return Response.ok("");
+      return Response.ok();
     } catch (MutuallyExclusiveLabelsException e) {
       throw new ResourceConflictException(e.getMessage());
     }
diff --git a/java/com/google/gerrit/server/restapi/change/Index.java b/java/com/google/gerrit/server/restapi/change/Index.java
index 5a17c07..5e17ae8 100644
--- a/java/com/google/gerrit/server/restapi/change/Index.java
+++ b/java/com/google/gerrit/server/restapi/change/Index.java
@@ -17,33 +17,29 @@
 import com.google.gerrit.extensions.common.Input;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.index.change.ChangeIndexer;
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.permissions.PermissionBackendException;
-import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
 
 @Singleton
-public class Index extends RetryingRestModifyView<ChangeResource, Input, Object> {
+public class Index implements RestModifyView<ChangeResource, Input> {
   private final PermissionBackend permissionBackend;
   private final ChangeIndexer indexer;
 
   @Inject
-  Index(RetryHelper retryHelper, PermissionBackend permissionBackend, ChangeIndexer indexer) {
-    super(retryHelper);
+  Index(PermissionBackend permissionBackend, ChangeIndexer indexer) {
     this.permissionBackend = permissionBackend;
     this.indexer = indexer;
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input input)
+  public Response<Object> apply(ChangeResource rsrc, Input input)
       throws IOException, AuthException, PermissionBackendException {
     permissionBackend.currentUser().check(GlobalPermission.MAINTAIN_SERVER);
     indexer.index(rsrc.getChange());
diff --git a/java/com/google/gerrit/server/restapi/change/ListChangeMessages.java b/java/com/google/gerrit/server/restapi/change/ListChangeMessages.java
index bfc9f12..099d0a6 100644
--- a/java/com/google/gerrit/server/restapi/change/ListChangeMessages.java
+++ b/java/com/google/gerrit/server/restapi/change/ListChangeMessages.java
@@ -32,18 +32,19 @@
 @Singleton
 public class ListChangeMessages implements RestReadView<ChangeResource> {
   private final ChangeMessagesUtil changeMessagesUtil;
-  private final AccountLoader accountLoader;
+  private final AccountLoader.Factory accountLoaderFactory;
 
   @Inject
   public ListChangeMessages(
       ChangeMessagesUtil changeMessagesUtil, AccountLoader.Factory accountLoaderFactory) {
     this.changeMessagesUtil = changeMessagesUtil;
-    this.accountLoader = accountLoaderFactory.create(true);
+    this.accountLoaderFactory = accountLoaderFactory;
   }
 
   @Override
   public Response<List<ChangeMessageInfo>> apply(ChangeResource resource)
       throws PermissionBackendException {
+    AccountLoader accountLoader = accountLoaderFactory.create(true);
     List<ChangeMessage> messages = changeMessagesUtil.byChange(resource.getNotes());
     List<ChangeMessageInfo> messageInfos =
         messages.stream()
diff --git a/java/com/google/gerrit/server/restapi/change/MarkAsReviewed.java b/java/com/google/gerrit/server/restapi/change/MarkAsReviewed.java
index 4c942d2..fa4555b 100644
--- a/java/com/google/gerrit/server/restapi/change/MarkAsReviewed.java
+++ b/java/com/google/gerrit/server/restapi/change/MarkAsReviewed.java
@@ -54,7 +54,7 @@
   public Response<String> apply(ChangeResource rsrc, Input input)
       throws RestApiException, IllegalLabelException {
     stars.markAsReviewed(rsrc);
-    return Response.ok("");
+    return Response.ok();
   }
 
   private boolean isReviewed(ChangeResource rsrc) {
diff --git a/java/com/google/gerrit/server/restapi/change/MarkAsUnreviewed.java b/java/com/google/gerrit/server/restapi/change/MarkAsUnreviewed.java
index 5945b14..601fc4a 100644
--- a/java/com/google/gerrit/server/restapi/change/MarkAsUnreviewed.java
+++ b/java/com/google/gerrit/server/restapi/change/MarkAsUnreviewed.java
@@ -52,7 +52,7 @@
   @Override
   public Response<String> apply(ChangeResource rsrc, Input input) throws IllegalLabelException {
     stars.markAsUnreviewed(rsrc);
-    return Response.ok("");
+    return Response.ok();
   }
 
   private boolean isReviewed(ChangeResource rsrc) {
diff --git a/java/com/google/gerrit/server/restapi/change/Module.java b/java/com/google/gerrit/server/restapi/change/Module.java
index a57bd64..539463f 100644
--- a/java/com/google/gerrit/server/restapi/change/Module.java
+++ b/java/com/google/gerrit/server/restapi/change/Module.java
@@ -96,6 +96,7 @@
     post(CHANGE_KIND, "hashtags").to(PostHashtags.class);
     post(CHANGE_KIND, "restore").to(Restore.class);
     post(CHANGE_KIND, "revert").to(Revert.class);
+    post(CHANGE_KIND, "revert_submission").to(RevertSubmission.class);
     post(CHANGE_KIND, "submit").to(Submit.CurrentRevision.class);
     get(CHANGE_KIND, "submitted_together").to(SubmittedTogether.class);
     post(CHANGE_KIND, "rebase").to(Rebase.CurrentRevision.class);
diff --git a/java/com/google/gerrit/server/restapi/change/Move.java b/java/com/google/gerrit/server/restapi/change/Move.java
index 7d4c4d1..51c512f 100644
--- a/java/com/google/gerrit/server/restapi/change/Move.java
+++ b/java/com/google/gerrit/server/restapi/change/Move.java
@@ -40,6 +40,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
@@ -59,8 +60,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -76,11 +75,11 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 
 @Singleton
-public class Move extends RetryingRestModifyView<ChangeResource, MoveInput, ChangeInfo>
-    implements UiAction<ChangeResource> {
+public class Move implements RestModifyView<ChangeResource, MoveInput>, UiAction<ChangeResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeJson.Factory json;
   private final GitRepositoryManager repoManager;
   private final Provider<InternalChangeQuery> queryProvider;
@@ -93,17 +92,17 @@
   @Inject
   Move(
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       ChangeJson.Factory json,
       GitRepositoryManager repoManager,
       Provider<InternalChangeQuery> queryProvider,
       ChangeMessagesUtil cmUtil,
-      RetryHelper retryHelper,
       PatchSetUtil psUtil,
       ApprovalsUtil approvalsUtil,
       ProjectCache projectCache,
       @GerritServerConfig Config gerritConfig) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.json = json;
     this.repoManager = repoManager;
     this.queryProvider = queryProvider;
@@ -115,8 +114,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, MoveInput input)
+  public Response<ChangeInfo> apply(ChangeResource rsrc, MoveInput input)
       throws RestApiException, UpdateException, PermissionBackendException, IOException {
     if (!moveEnabled) {
       // This will be removed with the above config once we reach consensus for the move change
diff --git a/java/com/google/gerrit/server/restapi/change/PostHashtags.java b/java/com/google/gerrit/server/restapi/change/PostHashtags.java
index 516dead..c1a6a13 100644
--- a/java/com/google/gerrit/server/restapi/change/PostHashtags.java
+++ b/java/com/google/gerrit/server/restapi/change/PostHashtags.java
@@ -18,14 +18,13 @@
 import com.google.gerrit.extensions.api.changes.HashtagsInput;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.SetHashtagsOp;
 import com.google.gerrit.server.permissions.ChangePermission;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -33,19 +32,18 @@
 
 @Singleton
 public class PostHashtags
-    extends RetryingRestModifyView<ChangeResource, HashtagsInput, ImmutableSortedSet<String>>
-    implements UiAction<ChangeResource> {
+    implements RestModifyView<ChangeResource, HashtagsInput>, UiAction<ChangeResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final SetHashtagsOp.Factory hashtagsFactory;
 
   @Inject
-  PostHashtags(RetryHelper retryHelper, SetHashtagsOp.Factory hashtagsFactory) {
-    super(retryHelper);
+  PostHashtags(BatchUpdate.Factory updateFactory, SetHashtagsOp.Factory hashtagsFactory) {
+    this.updateFactory = updateFactory;
     this.hashtagsFactory = hashtagsFactory;
   }
 
   @Override
-  protected Response<ImmutableSortedSet<String>> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource req, HashtagsInput input)
+  public Response<ImmutableSortedSet<String>> apply(ChangeResource req, HashtagsInput input)
       throws RestApiException, UpdateException, PermissionBackendException {
     req.permissions().check(ChangePermission.EDIT_HASHTAGS);
 
diff --git a/java/com/google/gerrit/server/restapi/change/PostPrivate.java b/java/com/google/gerrit/server/restapi/change/PostPrivate.java
index f008df3..f774457 100644
--- a/java/com/google/gerrit/server/restapi/change/PostPrivate.java
+++ b/java/com/google/gerrit/server/restapi/change/PostPrivate.java
@@ -18,11 +18,13 @@
 import static com.google.gerrit.extensions.conditions.BooleanCondition.or;
 
 import com.google.gerrit.entities.Change;
+import com.google.gerrit.extensions.common.InputWithMessage;
 import com.google.gerrit.extensions.conditions.BooleanCondition;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.MethodNotAllowedException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.SetPrivateOp;
@@ -30,8 +32,6 @@
 import com.google.gerrit.server.permissions.GlobalPermission;
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -39,27 +39,27 @@
 import org.eclipse.jgit.lib.Config;
 
 @Singleton
-public class PostPrivate extends RetryingRestModifyView<ChangeResource, SetPrivateOp.Input, String>
-    implements UiAction<ChangeResource> {
+public class PostPrivate
+    implements RestModifyView<ChangeResource, InputWithMessage>, UiAction<ChangeResource> {
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final SetPrivateOp.Factory setPrivateOpFactory;
   private final boolean disablePrivateChanges;
 
   @Inject
   PostPrivate(
-      RetryHelper retryHelper,
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       SetPrivateOp.Factory setPrivateOpFactory,
       @GerritServerConfig Config config) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.setPrivateOpFactory = setPrivateOpFactory;
     this.disablePrivateChanges = config.getBoolean("change", null, "disablePrivateChanges", false);
   }
 
   @Override
-  public Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, SetPrivateOp.Input input)
+  public Response<String> apply(ChangeResource rsrc, InputWithMessage input)
       throws RestApiException, UpdateException {
     if (disablePrivateChanges) {
       throw new MethodNotAllowedException("private changes are disabled");
@@ -70,7 +70,7 @@
     }
 
     if (rsrc.getChange().isPrivate()) {
-      return Response.ok("");
+      return Response.ok();
     }
 
     SetPrivateOp op = setPrivateOpFactory.create(true, input);
@@ -79,7 +79,7 @@
       u.addOp(rsrc.getId(), op).execute();
     }
 
-    return Response.created("");
+    return Response.created();
   }
 
   @Override
diff --git a/java/com/google/gerrit/server/restapi/change/PostReview.java b/java/com/google/gerrit/server/restapi/change/PostReview.java
index 974a72c..6f10839 100644
--- a/java/com/google/gerrit/server/restapi/change/PostReview.java
+++ b/java/com/google/gerrit/server/restapi/change/PostReview.java
@@ -73,6 +73,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.extensions.validators.CommentForValidation;
@@ -120,8 +121,6 @@
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.CommentsRejectedException;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.LabelVote;
 import com.google.gerrit.server.util.time.TimeUtil;
@@ -150,8 +149,7 @@
 import org.eclipse.jgit.lib.ObjectId;
 
 @Singleton
-public class PostReview
-    extends RetryingRestModifyView<RevisionResource, ReviewInput, ReviewResult> {
+public class PostReview implements RestModifyView<RevisionResource, ReviewInput> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private static final String ERROR_ADDING_REVIEWER = "error adding reviewer";
@@ -163,6 +161,7 @@
   private static final Gson GSON = OutputFormat.JSON_COMPACT.newGson();
   private static final int DEFAULT_ROBOT_COMMENT_SIZE_LIMIT_IN_BYTES = 1024 * 1024;
 
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeResource.Factory changeResourceFactory;
   private final ChangeData.Factory changeDataFactory;
   private final ApprovalsUtil approvalsUtil;
@@ -186,7 +185,7 @@
 
   @Inject
   PostReview(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       ChangeResource.Factory changeResourceFactory,
       ChangeData.Factory changeDataFactory,
       ApprovalsUtil approvalsUtil,
@@ -206,7 +205,7 @@
       ProjectCache projectCache,
       PermissionBackend permissionBackend,
       PluginSetContext<CommentValidator> commentValidators) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.changeResourceFactory = changeResourceFactory;
     this.changeDataFactory = changeDataFactory;
     this.commentsUtil = commentsUtil;
@@ -230,15 +229,13 @@
   }
 
   @Override
-  protected Response<ReviewResult> applyImpl(
-      BatchUpdate.Factory updateFactory, RevisionResource revision, ReviewInput input)
+  public Response<ReviewResult> apply(RevisionResource revision, ReviewInput input)
       throws RestApiException, UpdateException, IOException, PermissionBackendException,
           ConfigInvalidException, PatchListNotAvailableException {
-    return apply(updateFactory, revision, input, TimeUtil.nowTs());
+    return apply(revision, input, TimeUtil.nowTs());
   }
 
-  public Response<ReviewResult> apply(
-      BatchUpdate.Factory updateFactory, RevisionResource revision, ReviewInput input, Timestamp ts)
+  public Response<ReviewResult> apply(RevisionResource revision, ReviewInput input, Timestamp ts)
       throws RestApiException, UpdateException, IOException, PermissionBackendException,
           ConfigInvalidException, PatchListNotAvailableException {
     // Respect timestamp, but truncate at change created-on time.
@@ -249,6 +246,8 @@
     ProjectState projectState = projectCache.checkedGet(revision.getProject());
     LabelTypes labelTypes = projectState.getLabelTypes(revision.getNotes());
 
+    logger.atFine().log("strict label checking is %s", (strictLabels ? "enabled" : "disabled"));
+
     input.drafts = firstNonNull(input.drafts, DraftHandling.KEEP);
     logger.atFine().log("draft handling = %s", input.drafts);
 
@@ -270,6 +269,7 @@
     if (input.notify == null) {
       input.notify = defaultNotify(revision.getChange(), input);
     }
+    logger.atFine().log("notify handling = %s", input.notify);
 
     Map<String, AddReviewerResult> reviewerJsonResults = null;
     List<ReviewerAddition> reviewerResults = Lists.newArrayList();
@@ -282,13 +282,18 @@
             reviewerAdder.prepare(revision.getNotes(), revision.getUser(), reviewerInput, true);
         reviewerJsonResults.put(reviewerInput.reviewer, result.result);
         if (result.result.error != null) {
+          logger.atFine().log(
+              "Adding %s as reviewer failed: %s", reviewerInput.reviewer, result.result.error);
           hasError = true;
           continue;
         }
         if (result.result.confirm != null) {
+          logger.atFine().log(
+              "Adding %s as reviewer requires confirmation", reviewerInput.reviewer);
           confirm = true;
           continue;
         }
+        logger.atFine().log("Adding %s as reviewer was prepared", reviewerInput.reviewer);
         reviewerResults.add(result);
       }
     }
@@ -307,6 +312,9 @@
       boolean ccOrReviewer = false;
       if (input.labels != null && !input.labels.isEmpty()) {
         ccOrReviewer = input.labels.values().stream().anyMatch(v -> v != 0);
+        if (ccOrReviewer) {
+          logger.atFine().log("calling user is cc/reviewer on the change due to voting on a label");
+        }
       }
 
       if (!ccOrReviewer) {
@@ -314,17 +322,22 @@
         ReviewerSet currentReviewers =
             approvalsUtil.getReviewers(revision.getChangeResource().getNotes());
         ccOrReviewer = currentReviewers.all().contains(id);
+        if (ccOrReviewer) {
+          logger.atFine().log("calling user is already cc/reviewer on the change");
+        }
       }
 
       // Apply reviewer changes first. Revision emails should be sent to the
       // updated set of reviewers. Also keep track of whether the user added
       // themselves as a reviewer or to the CC list.
+      logger.atFine().log("adding reviewer additions");
       for (ReviewerAddition reviewerResult : reviewerResults) {
         reviewerResult.op.suppressEmail(); // Send a single batch email below.
         bu.addOp(revision.getChange().getId(), reviewerResult.op);
         if (!ccOrReviewer && reviewerResult.result.reviewers != null) {
           for (ReviewerInfo reviewerInfo : reviewerResult.result.reviewers) {
             if (Objects.equals(id.get(), reviewerInfo._accountId)) {
+              logger.atFine().log("calling user is explicitly added as reviewer");
               ccOrReviewer = true;
               break;
             }
@@ -333,6 +346,7 @@
         if (!ccOrReviewer && reviewerResult.result.ccs != null) {
           for (AccountInfo accountInfo : reviewerResult.result.ccs) {
             if (Objects.equals(id.get(), accountInfo._accountId)) {
+              logger.atFine().log("calling user is explicitly added as cc");
               ccOrReviewer = true;
               break;
             }
@@ -344,6 +358,7 @@
         // User posting this review isn't currently in the reviewer or CC list,
         // isn't being explicitly added, and isn't voting on any label.
         // Automatically CC them on this change so they receive replies.
+        logger.atFine().log("CCing calling user");
         ReviewerAddition selfAddition = reviewerAdder.ccCurrentUser(revision.getUser(), revision);
         selfAddition.op.suppressEmail();
         bu.addOp(revision.getChange().getId(), selfAddition.op);
@@ -365,6 +380,7 @@
           output.ready = true;
         }
 
+        logger.atFine().log("setting work-in-progress to %s", input.workInProgress);
         WorkInProgressOp wipOp =
             workInProgressOpFactory.create(input.workInProgress, new WorkInProgressOp.Input());
         wipOp.suppressEmail();
@@ -372,6 +388,7 @@
       }
 
       // Add the review op.
+      logger.atFine().log("posting review");
       bu.addOp(
           revision.getChange().getId(), new Op(projectState, revision.getPatchSet().id(), input));
 
@@ -455,6 +472,8 @@
   private RevisionResource onBehalfOf(RevisionResource rev, LabelTypes labelTypes, ReviewInput in)
       throws BadRequestException, AuthException, UnprocessableEntityException,
           PermissionBackendException, IOException, ConfigInvalidException {
+    logger.atFine().log("request is executed on behalf of %s", in.onBehalfOf);
+
     if (in.labels == null || in.labels.isEmpty()) {
       throw new AuthException(
           String.format("label required to post review on behalf of \"%s\"", in.onBehalfOf));
@@ -463,6 +482,8 @@
       throw new AuthException("not allowed to modify other user's drafts");
     }
 
+    logger.atFine().log("label input: %s", in.labels);
+
     CurrentUser caller = rev.getUser();
     PermissionBackend.ForChange perm = rev.permissions();
     Iterator<Map.Entry<String, Short>> itr = in.labels.entrySet().iterator();
@@ -470,15 +491,22 @@
       Map.Entry<String, Short> ent = itr.next();
       LabelType type = labelTypes.byLabel(ent.getKey());
       if (type == null) {
+        logger.atFine().log("label %s not found", ent.getKey());
         if (strictLabels) {
           throw new BadRequestException(
               String.format("label \"%s\" is not a configured label", ent.getKey()));
         }
+        logger.atFine().log("ignoring input for unknown label %s", ent.getKey());
         itr.remove();
         continue;
       }
 
-      if (!caller.isInternalUser()) {
+      if (caller.isInternalUser()) {
+        logger.atFine().log(
+            "skipping on behalf of permission check for label %s"
+                + " because caller is an internal user",
+            type.getName());
+      } else {
         try {
           perm.check(new LabelPermission.WithValue(ON_BEHALF_OF, type, ent.getValue()));
         } catch (AuthException e) {
@@ -490,11 +518,13 @@
       }
     }
     if (in.labels.isEmpty()) {
+      logger.atFine().log("labels are empty after unknown labels have been removed");
       throw new AuthException(
           String.format("label required to post review on behalf of \"%s\"", in.onBehalfOf));
     }
 
     IdentifiedUser reviewer = accountResolver.resolve(in.onBehalfOf).asUniqueUserOnBehalfOf(caller);
+    logger.atFine().log("on behalf of user was resolved to %s", reviewer.getLoggableName());
     try {
       permissionBackend.user(reviewer).change(rev.getNotes()).check(ChangePermission.READ);
     } catch (AuthException e) {
@@ -508,16 +538,20 @@
 
   private void checkLabels(RevisionResource rsrc, LabelTypes labelTypes, Map<String, Short> labels)
       throws BadRequestException, AuthException, PermissionBackendException {
+    logger.atFine().log("checking label input: %s", labels);
+
     PermissionBackend.ForChange perm = rsrc.permissions();
     Iterator<Map.Entry<String, Short>> itr = labels.entrySet().iterator();
     while (itr.hasNext()) {
       Map.Entry<String, Short> ent = itr.next();
       LabelType lt = labelTypes.byLabel(ent.getKey());
       if (lt == null) {
+        logger.atFine().log("label %s not found", ent.getKey());
         if (strictLabels) {
           throw new BadRequestException(
               String.format("label \"%s\" is not a configured label", ent.getKey()));
         }
+        logger.atFine().log("ignoring input for unknown label %s", ent.getKey());
         itr.remove();
         continue;
       }
@@ -529,10 +563,13 @@
       }
 
       if (lt.getValue(ent.getValue()) == null) {
+        logger.atFine().log("label value %s not found", ent.getValue());
         if (strictLabels) {
           throw new BadRequestException(
               String.format("label \"%s\": %d is not a valid value", ent.getKey(), ent.getValue()));
         }
+        logger.atFine().log(
+            "ignoring input for label %s because label value is unknown", ent.getKey());
         itr.remove();
         continue;
       }
@@ -576,6 +613,7 @@
   private <T extends CommentInput> void checkComments(
       RevisionResource revision, Map<String, List<T>> commentsPerPath)
       throws BadRequestException, PatchListNotAvailableException {
+    logger.atFine().log("checking comments");
     Set<String> revisionFilePaths = getAffectedFilePaths(revision);
     for (Map.Entry<String, List<T>> entry : commentsPerPath.entrySet()) {
       String path = entry.getKey();
@@ -628,6 +666,7 @@
   private void checkRobotComments(
       RevisionResource revision, Map<String, List<RobotCommentInput>> in)
       throws BadRequestException, PatchListNotAvailableException {
+    logger.atFine().log("checking robot comments");
     for (Map.Entry<String, List<RobotCommentInput>> e : in.entrySet()) {
       String commentPath = e.getKey();
       for (RobotCommentInput c : e.getValue()) {
diff --git a/java/com/google/gerrit/server/restapi/change/PostReviewers.java b/java/com/google/gerrit/server/restapi/change/PostReviewers.java
index f74643c..e6a87e9 100644
--- a/java/com/google/gerrit/server/restapi/change/PostReviewers.java
+++ b/java/com/google/gerrit/server/restapi/change/PostReviewers.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestCollectionModifyView;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.NotifyResolver;
 import com.google.gerrit.server.change.ReviewerAdder;
@@ -29,8 +30,6 @@
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestCollectionModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -40,28 +39,26 @@
 
 @Singleton
 public class PostReviewers
-    extends RetryingRestCollectionModifyView<
-        ChangeResource, ReviewerResource, AddReviewerInput, AddReviewerResult> {
-
+    implements RestCollectionModifyView<ChangeResource, ReviewerResource, AddReviewerInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeData.Factory changeDataFactory;
   private final NotifyResolver notifyResolver;
   private final ReviewerAdder reviewerAdder;
 
   @Inject
   PostReviewers(
+      BatchUpdate.Factory updateFactory,
       ChangeData.Factory changeDataFactory,
-      RetryHelper retryHelper,
       NotifyResolver notifyResolver,
       ReviewerAdder reviewerAdder) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.changeDataFactory = changeDataFactory;
     this.notifyResolver = notifyResolver;
     this.reviewerAdder = reviewerAdder;
   }
 
   @Override
-  protected Response<AddReviewerResult> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, AddReviewerInput input)
+  public Response<AddReviewerResult> apply(ChangeResource rsrc, AddReviewerInput input)
       throws IOException, RestApiException, UpdateException, PermissionBackendException,
           ConfigInvalidException {
     if (input.reviewer == null) {
diff --git a/java/com/google/gerrit/server/restapi/change/PublishChangeEdit.java b/java/com/google/gerrit/server/restapi/change/PublishChangeEdit.java
index 44f35a0..d76e53a 100644
--- a/java/com/google/gerrit/server/restapi/change/PublishChangeEdit.java
+++ b/java/com/google/gerrit/server/restapi/change/PublishChangeEdit.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.NotifyResolver;
 import com.google.gerrit.server.edit.ChangeEdit;
@@ -28,8 +29,6 @@
 import com.google.gerrit.server.project.ContributorAgreementsChecker;
 import com.google.gerrit.server.project.NoSuchProjectException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -38,27 +37,26 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class PublishChangeEdit
-    extends RetryingRestModifyView<ChangeResource, PublishChangeEditInput, Object> {
+public class PublishChangeEdit implements RestModifyView<ChangeResource, PublishChangeEditInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeEditUtil editUtil;
   private final NotifyResolver notifyResolver;
   private final ContributorAgreementsChecker contributorAgreementsChecker;
 
   @Inject
   PublishChangeEdit(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       ChangeEditUtil editUtil,
       NotifyResolver notifyResolver,
       ContributorAgreementsChecker contributorAgreementsChecker) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.editUtil = editUtil;
     this.notifyResolver = notifyResolver;
     this.contributorAgreementsChecker = contributorAgreementsChecker;
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, PublishChangeEditInput in)
+  public Response<Object> apply(ChangeResource rsrc, PublishChangeEditInput in)
       throws IOException, RestApiException, UpdateException, ConfigInvalidException,
           NoSuchProjectException {
     contributorAgreementsChecker.check(rsrc.getProject(), rsrc.getUser());
diff --git a/java/com/google/gerrit/server/restapi/change/PutAssignee.java b/java/com/google/gerrit/server/restapi/change/PutAssignee.java
index dd84624..dc1adfa 100644
--- a/java/com/google/gerrit/server/restapi/change/PutAssignee.java
+++ b/java/com/google/gerrit/server/restapi/change/PutAssignee.java
@@ -24,6 +24,7 @@
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.IdentifiedUser;
@@ -38,8 +39,6 @@
 import com.google.gerrit.server.permissions.PermissionBackend;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -48,9 +47,10 @@
 import org.eclipse.jgit.errors.ConfigInvalidException;
 
 @Singleton
-public class PutAssignee extends RetryingRestModifyView<ChangeResource, AssigneeInput, AccountInfo>
-    implements UiAction<ChangeResource> {
+public class PutAssignee
+    implements RestModifyView<ChangeResource, AssigneeInput>, UiAction<ChangeResource> {
 
+  private final BatchUpdate.Factory updateFactory;
   private final AccountResolver accountResolver;
   private final SetAssigneeOp.Factory assigneeFactory;
   private final ReviewerAdder reviewerAdder;
@@ -60,14 +60,14 @@
 
   @Inject
   PutAssignee(
+      BatchUpdate.Factory updateFactory,
       AccountResolver accountResolver,
       SetAssigneeOp.Factory assigneeFactory,
-      RetryHelper retryHelper,
       ReviewerAdder reviewerAdder,
       AccountLoader.Factory accountLoaderFactory,
       PermissionBackend permissionBackend,
       ApprovalsUtil approvalsUtil) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.accountResolver = accountResolver;
     this.assigneeFactory = assigneeFactory;
     this.reviewerAdder = reviewerAdder;
@@ -77,8 +77,7 @@
   }
 
   @Override
-  protected Response<AccountInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, AssigneeInput input)
+  public Response<AccountInfo> apply(ChangeResource rsrc, AssigneeInput input)
       throws RestApiException, UpdateException, IOException, PermissionBackendException,
           ConfigInvalidException {
     rsrc.permissions().check(ChangePermission.EDIT_ASSIGNEE);
diff --git a/java/com/google/gerrit/server/restapi/change/PutDescription.java b/java/com/google/gerrit/server/restapi/change/PutDescription.java
index 451d010..d84ab3e 100644
--- a/java/com/google/gerrit/server/restapi/change/PutDescription.java
+++ b/java/com/google/gerrit/server/restapi/change/PutDescription.java
@@ -20,6 +20,7 @@
 import com.google.gerrit.extensions.common.DescriptionInput;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.PatchSetUtil;
@@ -30,8 +31,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -39,21 +38,21 @@
 
 @Singleton
 public class PutDescription
-    extends RetryingRestModifyView<RevisionResource, DescriptionInput, String>
-    implements UiAction<RevisionResource> {
+    implements RestModifyView<RevisionResource, DescriptionInput>, UiAction<RevisionResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeMessagesUtil cmUtil;
   private final PatchSetUtil psUtil;
 
   @Inject
-  PutDescription(ChangeMessagesUtil cmUtil, RetryHelper retryHelper, PatchSetUtil psUtil) {
-    super(retryHelper);
+  PutDescription(
+      BatchUpdate.Factory updateFactory, ChangeMessagesUtil cmUtil, PatchSetUtil psUtil) {
+    this.updateFactory = updateFactory;
     this.cmUtil = cmUtil;
     this.psUtil = psUtil;
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, RevisionResource rsrc, DescriptionInput input)
+  public Response<String> apply(RevisionResource rsrc, DescriptionInput input)
       throws UpdateException, RestApiException, PermissionBackendException {
     rsrc.permissions().check(ChangePermission.EDIT_DESCRIPTION);
 
diff --git a/java/com/google/gerrit/server/restapi/change/PutDraftComment.java b/java/com/google/gerrit/server/restapi/change/PutDraftComment.java
index 5696fcb..63cd7a3 100644
--- a/java/com/google/gerrit/server/restapi/change/PutDraftComment.java
+++ b/java/com/google/gerrit/server/restapi/change/PutDraftComment.java
@@ -24,6 +24,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.Url;
 import com.google.gerrit.server.CommentsUtil;
 import com.google.gerrit.server.PatchSetUtil;
@@ -35,8 +36,6 @@
 import com.google.gerrit.server.update.BatchUpdate;
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -47,9 +46,8 @@
 import java.util.Optional;
 
 @Singleton
-public class PutDraftComment
-    extends RetryingRestModifyView<DraftCommentResource, DraftInput, CommentInfo> {
-
+public class PutDraftComment implements RestModifyView<DraftCommentResource, DraftInput> {
+  private final BatchUpdate.Factory updateFactory;
   private final DeleteDraftComment delete;
   private final CommentsUtil commentsUtil;
   private final PatchSetUtil psUtil;
@@ -58,13 +56,13 @@
 
   @Inject
   PutDraftComment(
+      BatchUpdate.Factory updateFactory,
       DeleteDraftComment delete,
       CommentsUtil commentsUtil,
       PatchSetUtil psUtil,
-      RetryHelper retryHelper,
       Provider<CommentJson> commentJson,
       PatchListCache patchListCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.delete = delete;
     this.commentsUtil = commentsUtil;
     this.psUtil = psUtil;
@@ -73,11 +71,10 @@
   }
 
   @Override
-  protected Response<CommentInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, DraftCommentResource rsrc, DraftInput in)
+  public Response<CommentInfo> apply(DraftCommentResource rsrc, DraftInput in)
       throws RestApiException, UpdateException, PermissionBackendException {
     if (in == null || in.message == null || in.message.trim().isEmpty()) {
-      return delete.applyImpl(updateFactory, rsrc, null);
+      return delete.apply(rsrc, null);
     } else if (in.id != null && !rsrc.getId().equals(in.id)) {
       throw new BadRequestException("id must match URL");
     } else if (in.line != null && in.line < 0) {
diff --git a/java/com/google/gerrit/server/restapi/change/PutMessage.java b/java/com/google/gerrit/server/restapi/change/PutMessage.java
index acda547..4761d0c3 100644
--- a/java/com/google/gerrit/server/restapi/change/PutMessage.java
+++ b/java/com/google/gerrit/server/restapi/change/PutMessage.java
@@ -24,6 +24,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.GerritPersonIdent;
@@ -38,8 +39,6 @@
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.CommitMessageUtil;
 import com.google.gerrit.server.util.time.TimeUtil;
@@ -61,8 +60,9 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 
 @Singleton
-public class PutMessage extends RetryingRestModifyView<ChangeResource, CommitMessageInput, String> {
+public class PutMessage implements RestModifyView<ChangeResource, CommitMessageInput> {
 
+  private final BatchUpdate.Factory updateFactory;
   private final GitRepositoryManager repositoryManager;
   private final Provider<CurrentUser> userProvider;
   private final TimeZone tz;
@@ -74,7 +74,7 @@
 
   @Inject
   PutMessage(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       GitRepositoryManager repositoryManager,
       Provider<CurrentUser> userProvider,
       PatchSetInserter.Factory psInserterFactory,
@@ -83,7 +83,7 @@
       PatchSetUtil psUtil,
       NotifyResolver notifyResolver,
       ProjectCache projectCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.repositoryManager = repositoryManager;
     this.userProvider = userProvider;
     this.psInserterFactory = psInserterFactory;
@@ -95,8 +95,7 @@
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource resource, CommitMessageInput input)
+  public Response<String> apply(ChangeResource resource, CommitMessageInput input)
       throws IOException, RestApiException, UpdateException, PermissionBackendException,
           ConfigInvalidException {
     PatchSet ps = psUtil.current(resource.getNotes());
diff --git a/java/com/google/gerrit/server/restapi/change/PutTopic.java b/java/com/google/gerrit/server/restapi/change/PutTopic.java
index cfeb884..f673bfc 100644
--- a/java/com/google/gerrit/server/restapi/change/PutTopic.java
+++ b/java/com/google/gerrit/server/restapi/change/PutTopic.java
@@ -21,6 +21,7 @@
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.ChangeUtil;
@@ -33,29 +34,27 @@
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class PutTopic extends RetryingRestModifyView<ChangeResource, TopicInput, String>
-    implements UiAction<ChangeResource> {
+public class PutTopic
+    implements RestModifyView<ChangeResource, TopicInput>, UiAction<ChangeResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final ChangeMessagesUtil cmUtil;
   private final TopicEdited topicEdited;
 
   @Inject
-  PutTopic(ChangeMessagesUtil cmUtil, RetryHelper retryHelper, TopicEdited topicEdited) {
-    super(retryHelper);
+  PutTopic(BatchUpdate.Factory updateFactory, ChangeMessagesUtil cmUtil, TopicEdited topicEdited) {
+    this.updateFactory = updateFactory;
     this.cmUtil = cmUtil;
     this.topicEdited = topicEdited;
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource req, TopicInput input)
+  public Response<String> apply(ChangeResource req, TopicInput input)
       throws UpdateException, RestApiException, PermissionBackendException {
     req.permissions().check(ChangePermission.EDIT_TOPIC_NAME);
 
diff --git a/java/com/google/gerrit/server/restapi/change/QueryChanges.java b/java/com/google/gerrit/server/restapi/change/QueryChanges.java
index 50e1e42..544177f 100644
--- a/java/com/google/gerrit/server/restapi/change/QueryChanges.java
+++ b/java/com/google/gerrit/server/restapi/change/QueryChanges.java
@@ -34,9 +34,11 @@
 import com.google.gerrit.server.query.change.ChangeQueryBuilder;
 import com.google.gerrit.server.query.change.ChangeQueryProcessor;
 import com.google.inject.Inject;
+import com.google.inject.Provider;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.EnumSet;
+import java.util.HashMap;
 import java.util.List;
 import org.kohsuke.args4j.Option;
 
@@ -45,8 +47,12 @@
 
   private final ChangeJson.Factory json;
   private final ChangeQueryBuilder qb;
-  private final ChangeQueryProcessor imp;
+  private final Provider<ChangeQueryProcessor> queryProcessorProvider;
+  private final HashMap<String, DynamicOptions.DynamicBean> dynamicBeans = new HashMap<>();
   private EnumSet<ListChangesOption> options;
+  private Integer limit;
+  private Integer start;
+  private Boolean noLimit;
 
   @Option(
       name = "--query",
@@ -61,7 +67,7 @@
       metaVar = "CNT",
       usage = "Maximum number of results to return")
   public void setLimit(int limit) {
-    imp.setUserProvidedLimit(limit);
+    this.limit = limit;
   }
 
   @Option(name = "-o", usage = "Output options per change")
@@ -80,24 +86,27 @@
       metaVar = "CNT",
       usage = "Number of changes to skip")
   public void setStart(int start) {
-    imp.setStart(start);
+    this.start = start;
   }
 
   @Option(name = "--no-limit", usage = "Return all results, overriding the default limit")
   public void setNoLimit(boolean on) {
-    imp.setNoLimit(on);
+    this.noLimit = on;
   }
 
   @Override
   public void setDynamicBean(String plugin, DynamicOptions.DynamicBean dynamicBean) {
-    imp.setDynamicBean(plugin, dynamicBean);
+    dynamicBeans.put(plugin, dynamicBean);
   }
 
   @Inject
-  QueryChanges(ChangeJson.Factory json, ChangeQueryBuilder qb, ChangeQueryProcessor qp) {
+  QueryChanges(
+      ChangeJson.Factory json,
+      ChangeQueryBuilder qb,
+      Provider<ChangeQueryProcessor> queryProcessorProvider) {
     this.json = json;
     this.qb = qb;
-    this.imp = qp;
+    this.queryProcessorProvider = queryProcessorProvider;
 
     options = EnumSet.noneOf(ListChangesOption.class);
   }
@@ -129,9 +138,22 @@
   }
 
   private List<List<ChangeInfo>> query() throws QueryParseException, PermissionBackendException {
-    if (imp.isDisabled()) {
+    ChangeQueryProcessor queryProcessor = queryProcessorProvider.get();
+    if (queryProcessor.isDisabled()) {
       throw new QueryParseException("query disabled");
     }
+
+    if (limit != null) {
+      queryProcessor.setUserProvidedLimit(limit);
+    }
+    if (start != null) {
+      queryProcessor.setStart(start);
+    }
+    if (noLimit != null) {
+      queryProcessor.setNoLimit(noLimit);
+    }
+    dynamicBeans.forEach((p, b) -> queryProcessor.setDynamicBean(p, b));
+
     if (queries == null || queries.isEmpty()) {
       queries = Collections.singletonList("status:open");
     } else if (queries.size() > 10) {
@@ -141,9 +163,9 @@
     }
 
     int cnt = queries.size();
-    List<QueryResult<ChangeData>> results = imp.query(qb.parse(queries));
+    List<QueryResult<ChangeData>> results = queryProcessor.query(qb.parse(queries));
     List<List<ChangeInfo>> res =
-        json.create(options, this.imp.getAttributesFactory()).format(results);
+        json.create(options, queryProcessor.getAttributesFactory()).format(results);
     for (int n = 0; n < cnt; n++) {
       List<ChangeInfo> info = res.get(n);
       if (results.get(n).more() && !info.isEmpty()) {
diff --git a/java/com/google/gerrit/server/restapi/change/Rebase.java b/java/com/google/gerrit/server/restapi/change/Rebase.java
index af8f971..7a9136b 100644
--- a/java/com/google/gerrit/server/restapi/change/Rebase.java
+++ b/java/com/google/gerrit/server/restapi/change/Rebase.java
@@ -47,8 +47,6 @@
 import com.google.gerrit.server.project.NoSuchChangeException;
 import com.google.gerrit.server.project.ProjectCache;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -63,13 +61,14 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 
 @Singleton
-public class Rebase extends RetryingRestModifyView<RevisionResource, RebaseInput, ChangeInfo>
+public class Rebase
     implements RestModifyView<RevisionResource, RebaseInput>, UiAction<RevisionResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private static final ImmutableSet<ListChangesOption> OPTIONS =
       Sets.immutableEnumSet(ListChangesOption.CURRENT_REVISION, ListChangesOption.CURRENT_COMMIT);
 
+  private final BatchUpdate.Factory updateFactory;
   private final GitRepositoryManager repoManager;
   private final RebaseChangeOp.Factory rebaseFactory;
   private final RebaseUtil rebaseUtil;
@@ -80,7 +79,7 @@
 
   @Inject
   public Rebase(
-      RetryHelper retryHelper,
+      BatchUpdate.Factory updateFactory,
       GitRepositoryManager repoManager,
       RebaseChangeOp.Factory rebaseFactory,
       RebaseUtil rebaseUtil,
@@ -88,7 +87,7 @@
       PermissionBackend permissionBackend,
       ProjectCache projectCache,
       PatchSetUtil patchSetUtil) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.repoManager = repoManager;
     this.rebaseFactory = rebaseFactory;
     this.rebaseUtil = rebaseUtil;
@@ -99,8 +98,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, RevisionResource rsrc, RebaseInput input)
+  public Response<ChangeInfo> apply(RevisionResource rsrc, RebaseInput input)
       throws UpdateException, RestApiException, IOException, PermissionBackendException {
     // Not allowed to rebase if the current patch set is locked.
     patchSetUtil.checkPatchSetNotLocked(rsrc.getNotes());
@@ -260,28 +258,24 @@
     return description;
   }
 
-  public static class CurrentRevision
-      extends RetryingRestModifyView<ChangeResource, RebaseInput, ChangeInfo> {
+  public static class CurrentRevision implements RestModifyView<ChangeResource, RebaseInput> {
     private final PatchSetUtil psUtil;
     private final Rebase rebase;
 
     @Inject
-    CurrentRevision(RetryHelper retryHelper, PatchSetUtil psUtil, Rebase rebase) {
-      super(retryHelper);
+    CurrentRevision(PatchSetUtil psUtil, Rebase rebase) {
       this.psUtil = psUtil;
       this.rebase = rebase;
     }
 
     @Override
-    protected Response<ChangeInfo> applyImpl(
-        BatchUpdate.Factory updateFactory, ChangeResource rsrc, RebaseInput input)
-        throws Exception {
+    public Response<ChangeInfo> apply(ChangeResource rsrc, RebaseInput input)
+        throws RestApiException, UpdateException, IOException, PermissionBackendException {
       PatchSet ps = psUtil.current(rsrc.getNotes());
       if (ps == null) {
         throw new ResourceConflictException("current revision is missing");
       }
-      return Response.ok(
-          rebase.applyImpl(updateFactory, new RevisionResource(rsrc, ps), input).value());
+      return Response.ok(rebase.apply(new RevisionResource(rsrc, ps), input).value());
     }
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/change/RebaseChangeEdit.java b/java/com/google/gerrit/server/restapi/change/RebaseChangeEdit.java
index 7be8765..9fb8de8 100644
--- a/java/com/google/gerrit/server/restapi/change/RebaseChangeEdit.java
+++ b/java/com/google/gerrit/server/restapi/change/RebaseChangeEdit.java
@@ -19,37 +19,30 @@
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.edit.ChangeEditModifier;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.project.InvalidChangeOperationException;
-import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
 import org.eclipse.jgit.lib.Repository;
 
 @Singleton
-public class RebaseChangeEdit extends RetryingRestModifyView<ChangeResource, Input, Object> {
+public class RebaseChangeEdit implements RestModifyView<ChangeResource, Input> {
   private final GitRepositoryManager repositoryManager;
   private final ChangeEditModifier editModifier;
 
   @Inject
-  RebaseChangeEdit(
-      RetryHelper retryHelper,
-      GitRepositoryManager repositoryManager,
-      ChangeEditModifier editModifier) {
-    super(retryHelper);
+  RebaseChangeEdit(GitRepositoryManager repositoryManager, ChangeEditModifier editModifier) {
     this.repositoryManager = repositoryManager;
     this.editModifier = editModifier;
   }
 
   @Override
-  protected Response<Object> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input in)
+  public Response<Object> apply(ChangeResource rsrc, Input in)
       throws AuthException, ResourceConflictException, IOException, PermissionBackendException {
     Project.NameKey project = rsrc.getProject();
     try (Repository repository = repositoryManager.openRepository(project)) {
diff --git a/java/com/google/gerrit/server/restapi/change/RelatedChangesSorter.java b/java/com/google/gerrit/server/restapi/change/RelatedChangesSorter.java
index 8040847..af65483 100644
--- a/java/com/google/gerrit/server/restapi/change/RelatedChangesSorter.java
+++ b/java/com/google/gerrit/server/restapi/change/RelatedChangesSorter.java
@@ -16,6 +16,7 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static java.util.Objects.requireNonNull;
+import static java.util.stream.Collectors.toMap;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.annotations.VisibleForTesting;
@@ -76,7 +77,15 @@
     // Map of all patch sets, keyed by commit SHA-1.
     Map<ObjectId, PatchSetData> byId = collectById(in);
     PatchSetData start = byId.get(startPs.commitId());
-    checkArgument(start != null, "%s not found in %s", startPs, in);
+    requireNonNull(
+        start,
+        () ->
+            String.format(
+                "commit %s of patch set %s not found in %s",
+                startPs.commitId().name(),
+                startPs.id(),
+                byId.entrySet().stream()
+                    .collect(toMap(e -> e.getKey().name(), e -> e.getValue().patchSet().id()))));
 
     // Map of patch set -> immediate parent.
     ListMultimap<PatchSetData, PatchSetData> parents =
diff --git a/java/com/google/gerrit/server/restapi/change/Restore.java b/java/com/google/gerrit/server/restapi/change/Restore.java
index 679d4f8..54575bb 100644
--- a/java/com/google/gerrit/server/restapi/change/Restore.java
+++ b/java/com/google/gerrit/server/restapi/change/Restore.java
@@ -26,6 +26,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ChangeMessagesUtil;
 import com.google.gerrit.server.ChangeUtil;
@@ -43,8 +44,6 @@
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -52,10 +51,11 @@
 import java.io.IOException;
 
 @Singleton
-public class Restore extends RetryingRestModifyView<ChangeResource, RestoreInput, ChangeInfo>
-    implements UiAction<ChangeResource> {
+public class Restore
+    implements RestModifyView<ChangeResource, RestoreInput>, UiAction<ChangeResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
+  private final BatchUpdate.Factory updateFactory;
   private final RestoredSender.Factory restoredSenderFactory;
   private final ChangeJson.Factory json;
   private final ChangeMessagesUtil cmUtil;
@@ -65,14 +65,14 @@
 
   @Inject
   Restore(
+      BatchUpdate.Factory updateFactory,
       RestoredSender.Factory restoredSenderFactory,
       ChangeJson.Factory json,
       ChangeMessagesUtil cmUtil,
       PatchSetUtil psUtil,
-      RetryHelper retryHelper,
       ChangeRestored changeRestored,
       ProjectCache projectCache) {
-    super(retryHelper);
+    this.updateFactory = updateFactory;
     this.restoredSenderFactory = restoredSenderFactory;
     this.json = json;
     this.cmUtil = cmUtil;
@@ -82,8 +82,7 @@
   }
 
   @Override
-  protected Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, RestoreInput input)
+  public Response<ChangeInfo> apply(ChangeResource rsrc, RestoreInput input)
       throws RestApiException, UpdateException, PermissionBackendException, IOException {
     // Not allowed to restore if the current patch set is locked.
     psUtil.checkPatchSetNotLocked(rsrc.getNotes());
diff --git a/java/com/google/gerrit/server/restapi/change/Revert.java b/java/com/google/gerrit/server/restapi/change/Revert.java
index dad87e5..d0b2562 100644
--- a/java/com/google/gerrit/server/restapi/change/Revert.java
+++ b/java/com/google/gerrit/server/restapi/change/Revert.java
@@ -31,6 +31,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ApprovalsUtil;
 import com.google.gerrit.server.ChangeMessagesUtil;
@@ -59,8 +60,6 @@
 import com.google.gerrit.server.update.BatchUpdateOp;
 import com.google.gerrit.server.update.ChangeContext;
 import com.google.gerrit.server.update.Context;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
@@ -79,11 +78,12 @@
 import org.eclipse.jgit.revwalk.RevWalk;
 
 @Singleton
-public class Revert extends RetryingRestModifyView<ChangeResource, RevertInput, ChangeInfo>
-    implements UiAction<ChangeResource> {
+public class Revert
+    implements RestModifyView<ChangeResource, RevertInput>, UiAction<ChangeResource> {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   private final PermissionBackend permissionBackend;
+  private final BatchUpdate.Factory updateFactory;
   private final GitRepositoryManager repoManager;
   private final ChangeInserter.Factory changeInserterFactory;
   private final ChangeMessagesUtil cmUtil;
@@ -101,10 +101,10 @@
   @Inject
   Revert(
       PermissionBackend permissionBackend,
+      BatchUpdate.Factory updateFactory,
       GitRepositoryManager repoManager,
       ChangeInserter.Factory changeInserterFactory,
       ChangeMessagesUtil cmUtil,
-      RetryHelper retryHelper,
       Sequences seq,
       PatchSetUtil psUtil,
       RevertedSender.Factory revertedSenderFactory,
@@ -115,8 +115,8 @@
       ProjectCache projectCache,
       NotifyResolver notifyResolver,
       CommitUtil commitUtil) {
-    super(retryHelper);
     this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
     this.repoManager = repoManager;
     this.changeInserterFactory = changeInserterFactory;
     this.cmUtil = cmUtil;
@@ -133,8 +133,7 @@
   }
 
   @Override
-  public Response<ChangeInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, RevertInput input)
+  public Response<ChangeInfo> apply(ChangeResource rsrc, RevertInput input)
       throws IOException, RestApiException, UpdateException, NoSuchChangeException,
           PermissionBackendException, NoSuchProjectException, ConfigInvalidException {
     Change change = rsrc.getChange();
diff --git a/java/com/google/gerrit/server/restapi/change/RevertSubmission.java b/java/com/google/gerrit/server/restapi/change/RevertSubmission.java
new file mode 100644
index 0000000..b44bb29
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/change/RevertSubmission.java
@@ -0,0 +1,181 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.change;
+
+import static com.google.gerrit.extensions.conditions.BooleanCondition.and;
+import static com.google.gerrit.server.permissions.RefPermission.CREATE_CHANGE;
+import static java.util.Objects.requireNonNull;
+
+import com.google.common.flogger.FluentLogger;
+import com.google.gerrit.entities.Change;
+import com.google.gerrit.extensions.api.changes.RevertInput;
+import com.google.gerrit.extensions.common.ChangeInfo;
+import com.google.gerrit.extensions.common.RevertSubmissionInfo;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.extensions.webui.UiAction;
+import com.google.gerrit.server.ChangeUtil;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.PatchSetUtil;
+import com.google.gerrit.server.change.ChangeResource;
+import com.google.gerrit.server.permissions.ChangePermission;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.project.ContributorAgreementsChecker;
+import com.google.gerrit.server.project.NoSuchChangeException;
+import com.google.gerrit.server.project.NoSuchProjectException;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.query.change.ChangeData;
+import com.google.gerrit.server.query.change.InternalChangeQuery;
+import com.google.gerrit.server.update.UpdateException;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.commons.lang.RandomStringUtils;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+@Singleton
+public class RevertSubmission
+    implements RestModifyView<ChangeResource, RevertInput>, UiAction<ChangeResource> {
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  private final Revert revert;
+  private final Provider<InternalChangeQuery> queryProvider;
+  private final ChangeResource.Factory changeResourceFactory;
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+  private final ProjectCache projectCache;
+  private final PatchSetUtil psUtil;
+  private final ContributorAgreementsChecker contributorAgreements;
+
+  @Inject
+  RevertSubmission(
+      Revert revert,
+      Provider<InternalChangeQuery> queryProvider,
+      ChangeResource.Factory changeResourceFactory,
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend,
+      ProjectCache projectCache,
+      PatchSetUtil psUtil,
+      ContributorAgreementsChecker contributorAgreements) {
+    this.revert = revert;
+    this.queryProvider = queryProvider;
+    this.changeResourceFactory = changeResourceFactory;
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+    this.projectCache = projectCache;
+    this.psUtil = psUtil;
+    this.contributorAgreements = contributorAgreements;
+  }
+
+  @Override
+  public Response<RevertSubmissionInfo> apply(ChangeResource changeResource, RevertInput input)
+      throws RestApiException, NoSuchChangeException, IOException, UpdateException,
+          PermissionBackendException, NoSuchProjectException, ConfigInvalidException {
+
+    if (!changeResource.getChange().isMerged()) {
+      throw new ResourceConflictException(
+          String.format("change is %s.", ChangeUtil.status(changeResource.getChange())));
+    }
+
+    String submissionId = changeResource.getChange().getSubmissionId();
+    if (submissionId == null) {
+      throw new ResourceConflictException(
+          "This change is merged but doesn't have a submission id,"
+              + " meaning it was not submitted through Gerrit.");
+    }
+    List<ChangeData> changeDatas = queryProvider.get().bySubmissionId(submissionId);
+
+    for (ChangeData changeData : changeDatas) {
+      Change change = changeData.change();
+
+      // Might do the permission tests multiple times, but these are necessary to ensure that the
+      // user has permissions to revert all changes. If they lack any permission, no revert will be
+      // done.
+
+      contributorAgreements.check(change.getProject(), changeResource.getUser());
+      permissionBackend.currentUser().ref(change.getDest()).check(CREATE_CHANGE);
+      permissionBackend.currentUser().change(changeData).check(ChangePermission.READ);
+      projectCache.checkedGet(change.getProject()).checkStatePermitsWrite();
+
+      requireNonNull(
+          psUtil.get(changeData.notes(), change.currentPatchSetId()),
+          String.format(
+              "current patch set %s of change %s not found",
+              change.currentPatchSetId(), change.currentPatchSetId()));
+    }
+    return Response.ok(revertSubmission(changeDatas, input, submissionId));
+  }
+
+  private RevertSubmissionInfo revertSubmission(
+      List<ChangeData> changeDatas, RevertInput input, String submissionId)
+      throws RestApiException, NoSuchChangeException, IOException, UpdateException,
+          PermissionBackendException, NoSuchProjectException, ConfigInvalidException {
+    List<ChangeInfo> results;
+    results = new ArrayList<>();
+    if (input.topic == null) {
+      input.topic =
+          String.format(
+              "revert-%s-%s", submissionId, RandomStringUtils.randomAlphabetic(10).toUpperCase());
+    }
+    for (ChangeData changeData : changeDatas) {
+      ChangeResource change = changeResourceFactory.create(changeData.notes(), user.get());
+      // Reverts are done with retrying by using RetryingRestModifyView.
+      results.add(revert.apply(change, input).value());
+    }
+    RevertSubmissionInfo revertSubmissionInfo = new RevertSubmissionInfo();
+    revertSubmissionInfo.revertChanges = results;
+    return revertSubmissionInfo;
+  }
+
+  @Override
+  public Description getDescription(ChangeResource rsrc) {
+    Change change = rsrc.getChange();
+    boolean projectStatePermitsWrite = false;
+    try {
+      projectStatePermitsWrite = projectCache.checkedGet(rsrc.getProject()).statePermitsWrite();
+    } catch (IOException e) {
+      logger.atSevere().withCause(e).log(
+          "Failed to check if project state permits write: %s", rsrc.getProject());
+    }
+    return new UiAction.Description()
+        .setLabel("Revert submission")
+        .setTitle(
+            "Revert this change and all changes that have been submitted together with this change")
+        .setVisible(
+            and(
+                change.isMerged()
+                    && change.getSubmissionId() != null
+                    && isChangePartOfSubmission(change.getSubmissionId())
+                    && projectStatePermitsWrite,
+                permissionBackend
+                    .user(rsrc.getUser())
+                    .ref(change.getDest())
+                    .testCond(CREATE_CHANGE)));
+  }
+
+  /**
+   * @param submissionId the submission id of the change.
+   * @return True if the submission has more than one change, false otherwise.
+   */
+  private Boolean isChangePartOfSubmission(String submissionId) {
+    return (queryProvider.get().setLimit(2).bySubmissionId(submissionId).size() > 1);
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/change/Reviewed.java b/java/com/google/gerrit/server/restapi/change/Reviewed.java
index 7152799..2793059 100644
--- a/java/com/google/gerrit/server/restapi/change/Reviewed.java
+++ b/java/com/google/gerrit/server/restapi/change/Reviewed.java
@@ -43,7 +43,7 @@
                       resource.getPatchKey().patchSetId(),
                       resource.getAccountId(),
                       resource.getPatchKey().fileName()));
-      return reviewFlagUpdated ? Response.created("") : Response.ok("");
+      return reviewFlagUpdated ? Response.created() : Response.ok();
     }
   }
 
diff --git a/java/com/google/gerrit/server/restapi/change/Reviewers.java b/java/com/google/gerrit/server/restapi/change/Reviewers.java
index b2714da..d702142 100644
--- a/java/com/google/gerrit/server/restapi/change/Reviewers.java
+++ b/java/com/google/gerrit/server/restapi/change/Reviewers.java
@@ -21,12 +21,11 @@
 import com.google.gerrit.extensions.restapi.IdString;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.RestView;
-import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.mail.Address;
 import com.google.gerrit.server.ApprovalsUtil;
+import com.google.gerrit.server.account.AccountResolver;
 import com.google.gerrit.server.change.ChangeResource;
 import com.google.gerrit.server.change.ReviewerResource;
-import com.google.gerrit.server.restapi.account.AccountsCollection;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 import java.io.IOException;
@@ -37,22 +36,22 @@
 public class Reviewers implements ChildCollection<ChangeResource, ReviewerResource> {
   private final DynamicMap<RestView<ReviewerResource>> views;
   private final ApprovalsUtil approvalsUtil;
-  private final AccountsCollection accounts;
   private final ReviewerResource.Factory resourceFactory;
   private final ListReviewers list;
+  private final AccountResolver accountResolver;
 
   @Inject
   Reviewers(
       ApprovalsUtil approvalsUtil,
-      AccountsCollection accounts,
       ReviewerResource.Factory resourceFactory,
       DynamicMap<RestView<ReviewerResource>> views,
-      ListReviewers list) {
+      ListReviewers list,
+      AccountResolver accountResolver) {
     this.approvalsUtil = approvalsUtil;
-    this.accounts = accounts;
     this.resourceFactory = resourceFactory;
     this.views = views;
     this.list = list;
+    this.accountResolver = accountResolver;
   }
 
   @Override
@@ -68,22 +67,18 @@
   @Override
   public ReviewerResource parse(ChangeResource rsrc, IdString id)
       throws ResourceNotFoundException, AuthException, IOException, ConfigInvalidException {
-    Address address = Address.tryParse(id.get());
-
-    Account.Id accountId = null;
     try {
-      accountId = accounts.parse(TopLevelResource.INSTANCE, id).getUser().getAccountId();
-    } catch (ResourceNotFoundException e) {
-      if (address == null) {
-        throw e;
+
+      AccountResolver.Result result = accountResolver.resolveIgnoreVisibility(id.get());
+      if (fetchAccountIds(rsrc).contains(result.asUniqueUser().getAccountId())) {
+        return resourceFactory.create(rsrc, result.asUniqueUser().getAccountId());
+      }
+    } catch (AccountResolver.UnresolvableAccountException e) {
+      if (e.isSelf()) {
+        throw new AuthException(e.getMessage(), e);
       }
     }
-    // See if the id exists as a reviewer for this change
-    if (accountId != null && fetchAccountIds(rsrc).contains(accountId)) {
-      return resourceFactory.create(rsrc, accountId);
-    }
-
-    // See if the address exists as a reviewer on the change
+    Address address = Address.tryParse(id.get());
     if (address != null && rsrc.getNotes().getReviewersByEmail().all().contains(address)) {
       return new ReviewerResource(rsrc, address);
     }
diff --git a/java/com/google/gerrit/server/restapi/change/SetReadyForReview.java b/java/com/google/gerrit/server/restapi/change/SetReadyForReview.java
index 288806c..8362e95 100644
--- a/java/com/google/gerrit/server/restapi/change/SetReadyForReview.java
+++ b/java/com/google/gerrit/server/restapi/change/SetReadyForReview.java
@@ -22,6 +22,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.change.ChangeResource;
@@ -31,27 +32,25 @@
 import com.google.gerrit.server.permissions.ChangePermission;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class SetReadyForReview extends RetryingRestModifyView<ChangeResource, Input, String>
-    implements UiAction<ChangeResource> {
+public class SetReadyForReview
+    implements RestModifyView<ChangeResource, Input>, UiAction<ChangeResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final WorkInProgressOp.Factory opFactory;
 
   @Inject
-  SetReadyForReview(RetryHelper retryHelper, WorkInProgressOp.Factory opFactory) {
-    super(retryHelper);
+  SetReadyForReview(BatchUpdate.Factory updateFactory, WorkInProgressOp.Factory opFactory) {
+    this.updateFactory = updateFactory;
     this.opFactory = opFactory;
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input input)
+  public Response<String> apply(ChangeResource rsrc, Input input)
       throws RestApiException, UpdateException, PermissionBackendException {
     rsrc.permissions().check(ChangePermission.TOGGLE_WORK_IN_PROGRESS_STATE);
 
@@ -69,7 +68,7 @@
       bu.setNotify(NotifyResolver.Result.create(firstNonNull(input.notify, NotifyHandling.ALL)));
       bu.addOp(rsrc.getChange().getId(), opFactory.create(false, input));
       bu.execute();
-      return Response.ok("");
+      return Response.ok();
     }
   }
 
diff --git a/java/com/google/gerrit/server/restapi/change/SetWorkInProgress.java b/java/com/google/gerrit/server/restapi/change/SetWorkInProgress.java
index 3fb0295..fdaad9d 100644
--- a/java/com/google/gerrit/server/restapi/change/SetWorkInProgress.java
+++ b/java/com/google/gerrit/server/restapi/change/SetWorkInProgress.java
@@ -22,6 +22,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.webui.UiAction;
 import com.google.gerrit.server.ChangeUtil;
 import com.google.gerrit.server.change.ChangeResource;
@@ -31,27 +32,25 @@
 import com.google.gerrit.server.permissions.ChangePermission;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
 @Singleton
-public class SetWorkInProgress extends RetryingRestModifyView<ChangeResource, Input, String>
-    implements UiAction<ChangeResource> {
+public class SetWorkInProgress
+    implements RestModifyView<ChangeResource, Input>, UiAction<ChangeResource> {
+  private final BatchUpdate.Factory updateFactory;
   private final WorkInProgressOp.Factory opFactory;
 
   @Inject
-  SetWorkInProgress(WorkInProgressOp.Factory opFactory, RetryHelper retryHelper) {
-    super(retryHelper);
+  SetWorkInProgress(BatchUpdate.Factory updateFactory, WorkInProgressOp.Factory opFactory) {
+    this.updateFactory = updateFactory;
     this.opFactory = opFactory;
   }
 
   @Override
-  protected Response<String> applyImpl(
-      BatchUpdate.Factory updateFactory, ChangeResource rsrc, Input input)
+  public Response<String> apply(ChangeResource rsrc, Input input)
       throws RestApiException, UpdateException, PermissionBackendException {
     rsrc.permissions().check(ChangePermission.TOGGLE_WORK_IN_PROGRESS_STATE);
 
@@ -69,7 +68,7 @@
       bu.setNotify(NotifyResolver.Result.create(firstNonNull(input.notify, NotifyHandling.NONE)));
       bu.addOp(rsrc.getChange().getId(), opFactory.create(true, input));
       bu.execute();
-      return Response.ok("");
+      return Response.ok();
     }
   }
 
diff --git a/java/com/google/gerrit/server/restapi/change/Submit.java b/java/com/google/gerrit/server/restapi/change/Submit.java
index 56dee3f..287c2bc 100644
--- a/java/com/google/gerrit/server/restapi/change/Submit.java
+++ b/java/com/google/gerrit/server/restapi/change/Submit.java
@@ -19,7 +19,6 @@
 
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Strings;
-import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ListMultimap;
 import com.google.common.collect.Sets;
@@ -190,7 +189,8 @@
   @UsedAt(UsedAt.Project.GOOGLE)
   public Response<Output> mergeChange(
       RevisionResource rsrc, IdentifiedUser submitter, SubmitInput input)
-      throws RestApiException, IOException {
+      throws RestApiException, IOException, UpdateException, ConfigInvalidException,
+          PermissionBackendException {
     Change change = rsrc.getChange();
     if (!change.isNew()) {
       throw new ResourceConflictException("change is " + ChangeUtil.status(change));
@@ -207,13 +207,7 @@
     try (MergeOp op = mergeOpProvider.get()) {
       Change updatedChange;
 
-      try {
-        updatedChange = op.merge(change, submitter, true, input, false);
-      } catch (Exception e) {
-        Throwables.throwIfInstanceOf(e, RestApiException.class);
-        return Response.<Output>internalServerError(e).traceId(op.getTraceId().orElse(null));
-      }
-
+      updatedChange = op.merge(change, submitter, true, input, false);
       if (updatedChange.isMerged()) {
         return Response.ok(new Output(change));
       }
@@ -471,12 +465,6 @@
       }
 
       Response<Output> response = submit.apply(new RevisionResource(rsrc, ps), input);
-      if (response instanceof Response.InternalServerError) {
-        Response.InternalServerError<?> ise = (Response.InternalServerError<?>) response;
-        return Response.<ChangeInfo>internalServerError(ise.cause())
-            .traceId(ise.traceId().orElse(null));
-      }
-
       return Response.ok(json.noOptions().format(response.value().change));
     }
   }
diff --git a/java/com/google/gerrit/server/restapi/change/Unignore.java b/java/com/google/gerrit/server/restapi/change/Unignore.java
index 26d3233..999e736 100644
--- a/java/com/google/gerrit/server/restapi/change/Unignore.java
+++ b/java/com/google/gerrit/server/restapi/change/Unignore.java
@@ -50,7 +50,7 @@
     if (isIgnored(rsrc)) {
       stars.unignore(rsrc);
     }
-    return Response.ok("");
+    return Response.ok();
   }
 
   private boolean isIgnored(ChangeResource rsrc) {
diff --git a/java/com/google/gerrit/server/restapi/config/FlushCache.java b/java/com/google/gerrit/server/restapi/config/FlushCache.java
index 9ea9e33..f10ed8d 100644
--- a/java/com/google/gerrit/server/restapi/config/FlushCache.java
+++ b/java/com/google/gerrit/server/restapi/config/FlushCache.java
@@ -50,6 +50,6 @@
     }
 
     rsrc.getCache().invalidateAll();
-    return Response.ok("");
+    return Response.ok();
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/config/PostCaches.java b/java/com/google/gerrit/server/restapi/config/PostCaches.java
index c633af0..c9480c5 100644
--- a/java/com/google/gerrit/server/restapi/config/PostCaches.java
+++ b/java/com/google/gerrit/server/restapi/config/PostCaches.java
@@ -84,13 +84,13 @@
               "specifying caches is not allowed for operation 'FLUSH_ALL'");
         }
         flushAll();
-        return Response.ok("");
+        return Response.ok();
       case FLUSH:
         if (input.caches == null || input.caches.isEmpty()) {
           throw new BadRequestException("caches must be specified for operation 'FLUSH'");
         }
         flush(input.caches);
-        return Response.ok("");
+        return Response.ok();
       default:
         throw new BadRequestException("unsupported operation: " + input.operation);
     }
diff --git a/java/com/google/gerrit/server/restapi/group/AddMembers.java b/java/com/google/gerrit/server/restapi/group/AddMembers.java
index 86d1283..b60d78e 100644
--- a/java/com/google/gerrit/server/restapi/group/AddMembers.java
+++ b/java/com/google/gerrit/server/restapi/group/AddMembers.java
@@ -28,6 +28,7 @@
 import com.google.gerrit.extensions.restapi.IdString;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.extensions.restapi.RestCollectionCreateView;
 import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
@@ -222,7 +223,8 @@
 
     @Override
     public Response<AccountInfo> apply(GroupResource resource, IdString id, Input input)
-        throws Exception {
+        throws RestApiException, NotInternalGroupException, IOException, ConfigInvalidException,
+            PermissionBackendException {
       AddMembers.Input in = new AddMembers.Input();
       in._oneMember = id.get();
       try {
diff --git a/java/com/google/gerrit/server/restapi/group/DeleteMembers.java b/java/com/google/gerrit/server/restapi/group/DeleteMembers.java
index 9bae2e2..fa1c5c6 100644
--- a/java/com/google/gerrit/server/restapi/group/DeleteMembers.java
+++ b/java/com/google/gerrit/server/restapi/group/DeleteMembers.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.restapi.group;
 
+import com.google.common.base.Strings;
 import com.google.common.collect.Sets;
 import com.google.gerrit.common.data.GroupDescription;
 import com.google.gerrit.entities.Account;
@@ -68,6 +69,9 @@
 
     Set<Account.Id> membersToRemove = new HashSet<>();
     for (String nameOrEmail : input.members) {
+      if (Strings.isNullOrEmpty(nameOrEmail)) {
+        continue;
+      }
       membersToRemove.add(accountResolver.resolve(nameOrEmail).asUnique().account().id());
     }
     AccountGroup.UUID groupUuid = internalGroup.getGroupUUID();
diff --git a/java/com/google/gerrit/server/restapi/group/GroupsCollection.java b/java/com/google/gerrit/server/restapi/group/GroupsCollection.java
index 52fe9d0..65a7f4f 100644
--- a/java/com/google/gerrit/server/restapi/group/GroupsCollection.java
+++ b/java/com/google/gerrit/server/restapi/group/GroupsCollection.java
@@ -42,7 +42,7 @@
   private final GroupResolver groupResolver;
   private final Provider<CurrentUser> self;
 
-  private boolean hasQuery2;
+  private boolean hasQuery;
 
   @Inject
   public GroupsCollection(
@@ -62,12 +62,7 @@
 
   @Override
   public void setParams(ListMultimap<String, String> params) throws BadRequestException {
-    if (params.containsKey("query") && params.containsKey("query2")) {
-      throw new BadRequestException("\"query\" and \"query2\" options are mutually exclusive");
-    }
-
-    // The --query2 option is defined in QueryGroups
-    this.hasQuery2 = params.containsKey("query2");
+    this.hasQuery = params.containsKey("query");
   }
 
   @Override
@@ -79,7 +74,7 @@
       throw new ResourceNotFoundException();
     }
 
-    if (hasQuery2) {
+    if (hasQuery) {
       return queryGroups.get();
     }
 
diff --git a/java/com/google/gerrit/server/restapi/group/ListGroups.java b/java/com/google/gerrit/server/restapi/group/ListGroups.java
index 899ed00..adc251c 100644
--- a/java/com/google/gerrit/server/restapi/group/ListGroups.java
+++ b/java/com/google/gerrit/server/restapi/group/ListGroups.java
@@ -129,21 +129,6 @@
     this.owned = owned;
   }
 
-  /**
-   * Add a group to inspect.
-   *
-   * @param uuid UUID of the group
-   * @deprecated use {@link #addGroup(AccountGroup.UUID)}.
-   */
-  @Deprecated
-  @Option(
-      name = "--query",
-      aliases = {"-q"},
-      usage = "group to inspect (deprecated: use --group/-g instead)")
-  void addGroup_Deprecated(AccountGroup.UUID uuid) {
-    addGroup(uuid);
-  }
-
   @Option(
       name = "--group",
       aliases = {"-g"},
diff --git a/java/com/google/gerrit/server/restapi/group/QueryGroups.java b/java/com/google/gerrit/server/restapi/group/QueryGroups.java
index a233111..380d42e 100644
--- a/java/com/google/gerrit/server/restapi/group/QueryGroups.java
+++ b/java/com/google/gerrit/server/restapi/group/QueryGroups.java
@@ -48,12 +48,9 @@
   private int start;
   private EnumSet<ListGroupsOption> options = EnumSet.noneOf(ListGroupsOption.class);
 
-  // TODO(ekempin): --query in ListGroups is marked as deprecated, once it is
-  // removed we want to rename --query2 to --query here.
-  /** --query (-q) is already used by {@link ListGroups} */
   @Option(
-      name = "--query2",
-      aliases = {"-q2"},
+      name = "--query",
+      aliases = {"-q"},
       usage = "group query")
   public void setQuery(String query) {
     this.query = query;
diff --git a/java/com/google/gerrit/server/restapi/project/BanCommit.java b/java/com/google/gerrit/server/restapi/project/BanCommit.java
index 64e38b0..a20d462 100644
--- a/java/com/google/gerrit/server/restapi/project/BanCommit.java
+++ b/java/com/google/gerrit/server/restapi/project/BanCommit.java
@@ -18,14 +18,11 @@
 import com.google.gerrit.extensions.api.projects.BanCommitInput;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
 import com.google.gerrit.server.git.BanCommitResult;
 import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.project.ProjectResource;
-import com.google.gerrit.server.restapi.project.BanCommit.BanResultInfo;
-import com.google.gerrit.server.update.BatchUpdate;
-import com.google.gerrit.server.update.RetryHelper;
-import com.google.gerrit.server.update.RetryingRestModifyView;
 import com.google.gerrit.server.update.UpdateException;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
@@ -35,19 +32,16 @@
 import org.eclipse.jgit.lib.ObjectId;
 
 @Singleton
-public class BanCommit
-    extends RetryingRestModifyView<ProjectResource, BanCommitInput, BanResultInfo> {
+public class BanCommit implements RestModifyView<ProjectResource, BanCommitInput> {
   private final com.google.gerrit.server.git.BanCommit banCommit;
 
   @Inject
-  BanCommit(RetryHelper retryHelper, com.google.gerrit.server.git.BanCommit banCommit) {
-    super(retryHelper);
+  BanCommit(com.google.gerrit.server.git.BanCommit banCommit) {
     this.banCommit = banCommit;
   }
 
   @Override
-  protected Response<BanResultInfo> applyImpl(
-      BatchUpdate.Factory updateFactory, ProjectResource rsrc, BanCommitInput input)
+  public Response<BanResultInfo> apply(ProjectResource rsrc, BanCommitInput input)
       throws RestApiException, UpdateException, IOException, PermissionBackendException {
     BanResultInfo r = new BanResultInfo();
     if (input != null && input.commits != null && !input.commits.isEmpty()) {
diff --git a/java/com/google/gerrit/server/restapi/project/CommitsCollection.java b/java/com/google/gerrit/server/restapi/project/CommitsCollection.java
index 334447b..7c88ab3 100644
--- a/java/com/google/gerrit/server/restapi/project/CommitsCollection.java
+++ b/java/com/google/gerrit/server/restapi/project/CommitsCollection.java
@@ -26,6 +26,7 @@
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.extensions.restapi.RestView;
+import com.google.gerrit.index.query.Predicate;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.index.change.ChangeIndexCollection;
 import com.google.gerrit.server.project.CommitResource;
@@ -33,7 +34,9 @@
 import com.google.gerrit.server.project.ProjectState;
 import com.google.gerrit.server.project.Reachable;
 import com.google.gerrit.server.query.change.ChangeData;
+import com.google.gerrit.server.query.change.CommitPredicate;
 import com.google.gerrit.server.query.change.InternalChangeQuery;
+import com.google.gerrit.server.query.change.ProjectPredicate;
 import com.google.gerrit.server.update.RetryHelper;
 import com.google.gerrit.server.update.RetryHelper.Action;
 import com.google.gerrit.server.update.RetryHelper.ActionType;
@@ -41,7 +44,11 @@
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import java.io.IOException;
+import java.util.Arrays;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
+import java.util.stream.Collectors;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.errors.MissingObjectException;
 import org.eclipse.jgit.lib.ObjectId;
@@ -116,12 +123,13 @@
   public boolean canRead(ProjectState state, Repository repo, RevCommit commit) throws IOException {
     Project.NameKey project = state.getNameKey();
     if (indexes.getSearchIndex() == null) {
-      // No index in slaves, fall back to scanning refs.
+      // No index in slaves, fall back to scanning refs. We must inspect change refs too
+      // as the commit might be a patchset of a not yet submitted change.
       return reachable.fromRefs(project, repo, commit, repo.getRefDatabase().getRefs());
     }
 
-    // Check first if any change references the commit in question. This is much cheaper than ref
-    // visibility filtering and reachability computation.
+    // Check first if any patchset of any change references the commit in question. This is much
+    // cheaper than ref visibility filtering and reachability computation.
     List<ChangeData> changes =
         executeIndexQuery(
             () ->
@@ -134,6 +142,30 @@
       return true;
     }
 
+    // Maybe the commit was a merge commit of a change. Try to find promising candidates for
+    // branches to check, by seeing if its parents were associated to changes.
+    Predicate<ChangeData> pred =
+        Predicate.and(
+            new ProjectPredicate(project.get()),
+            Predicate.or(
+                Arrays.stream(commit.getParents())
+                    .map(parent -> new CommitPredicate(parent.getId().getName()))
+                    .collect(toImmutableList())));
+    changes = executeIndexQuery(() -> queryProvider.get().enforceVisibility(true).query(pred));
+
+    Set<Ref> branchesForCommitParents = new HashSet<>(changes.size());
+    for (ChangeData cd : changes) {
+      Ref ref = repo.exactRef(cd.change().getDest().branch());
+      if (ref != null) {
+        branchesForCommitParents.add(ref);
+      }
+    }
+
+    if (reachable.fromRefs(
+        project, repo, commit, branchesForCommitParents.stream().collect(Collectors.toList()))) {
+      return true;
+    }
+
     // If we have already checked change refs using the change index, spare any further checks for
     // changes.
     List<Ref> refs =
diff --git a/java/com/google/gerrit/server/restapi/project/CreateBranch.java b/java/com/google/gerrit/server/restapi/project/CreateBranch.java
index c036c78..56948c1 100644
--- a/java/com/google/gerrit/server/restapi/project/CreateBranch.java
+++ b/java/com/google/gerrit/server/restapi/project/CreateBranch.java
@@ -27,6 +27,7 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestCollectionCreateView;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
 import com.google.gerrit.server.git.GitRepositoryManager;
@@ -159,8 +160,7 @@
               }
               refPrefix = RefUtil.getRefPrefix(refPrefix);
             }
-            // fall through
-            // $FALL-THROUGH$
+            throw new LockFailureException(String.format("Failed to create %s", ref), u);
           case FORCED:
           case IO_FAILURE:
           case NOT_ATTEMPTED:
@@ -170,9 +170,7 @@
           case REJECTED_MISSING_OBJECT:
           case REJECTED_OTHER_REASON:
           default:
-            {
-              throw new IOException(result.name());
-            }
+            throw new IOException(String.format("Failed to create %s: %s", ref, result.name()));
         }
 
         BranchInfo info = new BranchInfo();
diff --git a/java/com/google/gerrit/server/restapi/project/CreateDashboard.java b/java/com/google/gerrit/server/restapi/project/CreateDashboard.java
index 314df73..9904b1f 100644
--- a/java/com/google/gerrit/server/restapi/project/CreateDashboard.java
+++ b/java/com/google/gerrit/server/restapi/project/CreateDashboard.java
@@ -19,12 +19,15 @@
 import com.google.gerrit.extensions.restapi.IdString;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.extensions.restapi.RestCollectionCreateView;
+import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.project.DashboardResource;
 import com.google.gerrit.server.project.ProjectResource;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
+import java.io.IOException;
 import org.kohsuke.args4j.Option;
 
 @Singleton
@@ -42,7 +45,7 @@
 
   @Override
   public Response<DashboardInfo> apply(ProjectResource parent, IdString id, SetDashboardInput input)
-      throws Exception {
+      throws RestApiException, IOException, PermissionBackendException {
     parent.getProjectState().checkStatePermitsWrite();
     if (!DashboardsCollection.isDefaultDashboard(id)) {
       throw new ResourceNotFoundException(id);
diff --git a/java/com/google/gerrit/server/restapi/project/CreateLabel.java b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
new file mode 100644
index 0000000..5d51527
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
@@ -0,0 +1,206 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.common.data.LabelValue;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.IdString;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestCollectionCreateView;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.git.meta.MetaDataUpdate;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelDefinitionJson;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectConfig;
+import com.google.gerrit.server.project.ProjectResource;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.util.List;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+@Singleton
+public class CreateLabel
+    implements RestCollectionCreateView<ProjectResource, LabelResource, LabelDefinitionInput> {
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+  private final MetaDataUpdate.User updateFactory;
+  private final ProjectConfig.Factory projectConfigFactory;
+  private final ProjectCache projectCache;
+
+  @Inject
+  public CreateLabel(
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend,
+      MetaDataUpdate.User updateFactory,
+      ProjectConfig.Factory projectConfigFactory,
+      ProjectCache projectCache) {
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
+    this.projectConfigFactory = projectConfigFactory;
+    this.projectCache = projectCache;
+  }
+
+  @Override
+  public Response<LabelDefinitionInfo> apply(
+      ProjectResource rsrc, IdString id, LabelDefinitionInput input)
+      throws AuthException, BadRequestException, ResourceConflictException,
+          PermissionBackendException, IOException, ConfigInvalidException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    permissionBackend
+        .currentUser()
+        .project(rsrc.getNameKey())
+        .check(ProjectPermission.WRITE_CONFIG);
+
+    if (input == null) {
+      input = new LabelDefinitionInput();
+    }
+
+    if (input.name != null && !input.name.equals(id.get())) {
+      throw new BadRequestException("name in input must match name in URL");
+    }
+
+    try (MetaDataUpdate md = updateFactory.create(rsrc.getNameKey())) {
+      ProjectConfig config = projectConfigFactory.read(md);
+
+      LabelType labelType = createLabel(config, id.get(), input);
+
+      if (input.commitMessage != null) {
+        md.setMessage(Strings.emptyToNull(input.commitMessage.trim()));
+      } else {
+        md.setMessage("Update label");
+      }
+
+      config.commit(md);
+
+      projectCache.evict(rsrc.getProjectState().getProject());
+
+      return Response.created(LabelDefinitionJson.format(rsrc.getNameKey(), labelType));
+    }
+  }
+
+  /**
+   * Creates a new label.
+   *
+   * @param config the project config
+   * @param label the name of the new label
+   * @param input the input that describes the new label
+   * @return the created label type
+   * @throws BadRequestException if there was invalid data in the input
+   * @throws ResourceConflictException if the label cannot be created due to a conflict
+   */
+  public LabelType createLabel(ProjectConfig config, String label, LabelDefinitionInput input)
+      throws BadRequestException, ResourceConflictException {
+    if (config.getLabelSections().containsKey(label)) {
+      throw new ResourceConflictException(String.format("label %s already exists", label));
+    }
+
+    for (String labelName : config.getLabelSections().keySet()) {
+      if (labelName.equalsIgnoreCase(label)) {
+        throw new ResourceConflictException(
+            String.format("label %s conflicts with existing label %s", label, labelName));
+      }
+    }
+
+    if (input.values == null || input.values.isEmpty()) {
+      throw new BadRequestException("values are required");
+    }
+
+    List<LabelValue> values = LabelDefinitionInputParser.parseValues(input.values);
+
+    LabelType labelType;
+    try {
+      labelType = new LabelType(label, values);
+    } catch (IllegalArgumentException e) {
+      throw new BadRequestException("invalid name: " + label, e);
+    }
+
+    if (input.function != null && !input.function.trim().isEmpty()) {
+      labelType.setFunction(LabelDefinitionInputParser.parseFunction(input.function));
+    } else {
+      labelType.setFunction(LabelFunction.MAX_WITH_BLOCK);
+    }
+
+    if (input.defaultValue != null) {
+      labelType.setDefaultValue(
+          LabelDefinitionInputParser.parseDefaultValue(labelType, input.defaultValue));
+    }
+
+    if (input.branches != null) {
+      labelType.setRefPatterns(LabelDefinitionInputParser.parseBranches(input.branches));
+    }
+
+    if (input.canOverride != null) {
+      labelType.setCanOverride(input.canOverride);
+    }
+
+    if (input.copyAnyScore != null) {
+      labelType.setCopyAnyScore(input.copyAnyScore);
+    }
+
+    if (input.copyMinScore != null) {
+      labelType.setCopyMinScore(input.copyMinScore);
+    }
+
+    if (input.copyMaxScore != null) {
+      labelType.setCopyMaxScore(input.copyMaxScore);
+    }
+
+    if (input.copyAllScoresIfNoChange != null) {
+      labelType.setCopyAllScoresIfNoChange(input.copyAllScoresIfNoChange);
+    }
+
+    if (input.copyAllScoresIfNoCodeChange != null) {
+      labelType.setCopyAllScoresIfNoCodeChange(input.copyAllScoresIfNoCodeChange);
+    }
+
+    if (input.copyAllScoresOnTrivialRebase != null) {
+      labelType.setCopyAllScoresOnTrivialRebase(input.copyAllScoresOnTrivialRebase);
+    }
+
+    if (input.copyAllScoresOnMergeFirstParentUpdate != null) {
+      labelType.setCopyAllScoresOnMergeFirstParentUpdate(
+          input.copyAllScoresOnMergeFirstParentUpdate);
+    }
+
+    if (input.allowPostSubmit != null) {
+      labelType.setAllowPostSubmit(input.allowPostSubmit);
+    }
+
+    if (input.ignoreSelfApproval != null) {
+      labelType.setIgnoreSelfApproval(input.ignoreSelfApproval);
+    }
+
+    config.getLabelSections().put(labelType.getName(), labelType);
+
+    return labelType;
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/DeleteLabel.java b/java/com/google/gerrit/server/restapi/project/DeleteLabel.java
new file mode 100644
index 0000000..531640c
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/DeleteLabel.java
@@ -0,0 +1,113 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.extensions.common.InputWithCommitMessage;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.IdString;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.git.meta.MetaDataUpdate;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectConfig;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+@Singleton
+public class DeleteLabel implements RestModifyView<LabelResource, InputWithCommitMessage> {
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+  private final MetaDataUpdate.User updateFactory;
+  private final ProjectConfig.Factory projectConfigFactory;
+  private final ProjectCache projectCache;
+
+  @Inject
+  public DeleteLabel(
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend,
+      MetaDataUpdate.User updateFactory,
+      ProjectConfig.Factory projectConfigFactory,
+      ProjectCache projectCache) {
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
+    this.projectConfigFactory = projectConfigFactory;
+    this.projectCache = projectCache;
+  }
+
+  @Override
+  public Response<?> apply(LabelResource rsrc, InputWithCommitMessage input)
+      throws AuthException, ResourceNotFoundException, PermissionBackendException, IOException,
+          ConfigInvalidException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    permissionBackend
+        .currentUser()
+        .project(rsrc.getProject().getNameKey())
+        .check(ProjectPermission.WRITE_CONFIG);
+
+    if (input == null) {
+      input = new InputWithCommitMessage();
+    }
+
+    try (MetaDataUpdate md = updateFactory.create(rsrc.getProject().getNameKey())) {
+      ProjectConfig config = projectConfigFactory.read(md);
+
+      if (!deleteLabel(config, rsrc.getLabelType().getName())) {
+        throw new ResourceNotFoundException(IdString.fromDecoded(rsrc.getLabelType().getName()));
+      }
+
+      if (input.commitMessage != null) {
+        md.setMessage(Strings.emptyToNull(input.commitMessage.trim()));
+      } else {
+        md.setMessage("Delete label");
+      }
+
+      config.commit(md);
+    }
+
+    projectCache.evict(rsrc.getProject().getProjectState().getProject());
+
+    return Response.none();
+  }
+
+  /**
+   * Delete the given label from the given project config.
+   *
+   * @param config the project config from which the label should be deleted
+   * @param labelName the name of the label that should be deleted
+   * @return {@code true} if the label was deleted, {@code false} if the label was not found
+   */
+  public boolean deleteLabel(ProjectConfig config, String labelName) {
+    if (!config.getLabelSections().containsKey(labelName)) {
+      return false;
+    }
+
+    config.getLabelSections().remove(labelName);
+    return true;
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/DeleteRef.java b/java/com/google/gerrit/server/restapi/project/DeleteRef.java
index 1979d61..2395bdd 100644
--- a/java/com/google/gerrit/server/restapi/project/DeleteRef.java
+++ b/java/com/google/gerrit/server/restapi/project/DeleteRef.java
@@ -30,6 +30,7 @@
 import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.extensions.events.GitReferenceUpdated;
 import com.google.gerrit.server.git.GitRepositoryManager;
@@ -43,7 +44,6 @@
 import com.google.inject.Provider;
 import com.google.inject.Singleton;
 import java.io.IOException;
-import org.eclipse.jgit.errors.LockFailedException;
 import org.eclipse.jgit.lib.BatchRefUpdate;
 import org.eclipse.jgit.lib.NullProgressMonitor;
 import org.eclipse.jgit.lib.ObjectId;
@@ -58,9 +58,6 @@
 public class DeleteRef {
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
-  private static final int MAX_LOCK_FAILURE_CALLS = 10;
-  private static final long SLEEP_ON_LOCK_FAILURE_MS = 15;
-
   private final Provider<IdentifiedUser> identifiedUser;
   private final PermissionBackend permissionBackend;
   private final GitRepositoryManager repoManager;
@@ -126,23 +123,7 @@
       u.setNewObjectId(ObjectId.zeroId());
       u.setForceUpdate(true);
       refDeletionValidator.validateRefOperation(projectState.getName(), identifiedUser.get(), u);
-      int remainingLockFailureCalls = MAX_LOCK_FAILURE_CALLS;
-      for (; ; ) {
-        try {
-          result = u.delete();
-        } catch (LockFailedException e) {
-          result = RefUpdate.Result.LOCK_FAILURE;
-        }
-        if (result == RefUpdate.Result.LOCK_FAILURE && --remainingLockFailureCalls > 0) {
-          try {
-            Thread.sleep(SLEEP_ON_LOCK_FAILURE_MS);
-          } catch (InterruptedException ie) {
-            // ignore
-          }
-        } else {
-          break;
-        }
-      }
+      result = u.delete();
 
       switch (result) {
         case NEW:
@@ -160,8 +141,9 @@
           logger.atFine().log("Cannot delete current branch %s: %s", ref, result.name());
           throw new ResourceConflictException("cannot delete current branch");
 
-        case IO_FAILURE:
         case LOCK_FAILURE:
+          throw new LockFailureException(String.format("Cannot delete %s", ref), u);
+        case IO_FAILURE:
         case NOT_ATTEMPTED:
         case REJECTED:
         case RENAMED:
diff --git a/java/com/google/gerrit/server/restapi/project/GetLabel.java b/java/com/google/gerrit/server/restapi/project/GetLabel.java
new file mode 100644
index 0000000..626cb42
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/GetLabel.java
@@ -0,0 +1,34 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestReadView;
+import com.google.gerrit.server.project.LabelDefinitionJson;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.inject.Singleton;
+
+@Singleton
+public class GetLabel implements RestReadView<LabelResource> {
+  @Override
+  public Response<LabelDefinitionInfo> apply(LabelResource rsrc)
+      throws AuthException, BadRequestException {
+    return Response.ok(
+        LabelDefinitionJson.format(rsrc.getProject().getNameKey(), rsrc.getLabelType()));
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java b/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java
new file mode 100644
index 0000000..1e288f4
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java
@@ -0,0 +1,93 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.common.primitives.Shorts;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.common.data.LabelValue;
+import com.google.gerrit.common.data.PermissionRule;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.exceptions.InvalidNameException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.server.project.RefPattern;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.Set;
+
+public class LabelDefinitionInputParser {
+  public static LabelFunction parseFunction(String functionString) throws BadRequestException {
+    Optional<LabelFunction> function = LabelFunction.parse(functionString.trim());
+    return function.orElseThrow(
+        () -> new BadRequestException("unknown function: " + functionString));
+  }
+
+  public static List<LabelValue> parseValues(Map<String, String> values)
+      throws BadRequestException {
+    List<LabelValue> valueList = new ArrayList<>();
+    Set<Short> allValues = new HashSet<>();
+    for (Entry<String, String> e : values.entrySet()) {
+      short value;
+      try {
+        value = Shorts.checkedCast(PermissionRule.parseInt(e.getKey().trim()));
+      } catch (NumberFormatException ex) {
+        throw new BadRequestException("invalid value: " + e.getKey(), ex);
+      }
+      if (!allValues.add(value)) {
+        throw new BadRequestException("duplicate value: " + value);
+      }
+      String valueDescription = e.getValue().trim();
+      if (valueDescription.isEmpty()) {
+        throw new BadRequestException("description for value '" + e.getKey() + "' cannot be empty");
+      }
+      valueList.add(new LabelValue(value, valueDescription));
+    }
+    return valueList;
+  }
+
+  public static short parseDefaultValue(LabelType labelType, short defaultValue)
+      throws BadRequestException {
+    if (labelType.getValue(defaultValue) == null) {
+      throw new BadRequestException("invalid default value: " + defaultValue);
+    }
+    return defaultValue;
+  }
+
+  public static List<String> parseBranches(List<String> branches) throws BadRequestException {
+    List<String> validBranches = new ArrayList<>();
+    for (String branch : branches) {
+      String newBranch = branch.trim();
+      if (newBranch.isEmpty()) {
+        continue;
+      }
+      if (!RefPattern.isRE(newBranch) && !newBranch.startsWith(RefNames.REFS)) {
+        newBranch = RefNames.REFS_HEADS + newBranch;
+      }
+      try {
+        RefPattern.validate(newBranch);
+      } catch (InvalidNameException e) {
+        throw new BadRequestException("invalid branch: " + branch, e);
+      }
+      validBranches.add(newBranch);
+    }
+    return validBranches;
+  }
+
+  private LabelDefinitionInputParser() {}
+}
diff --git a/java/com/google/gerrit/server/restapi/project/LabelsCollection.java b/java/com/google/gerrit/server/restapi/project/LabelsCollection.java
new file mode 100644
index 0000000..0409729
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/LabelsCollection.java
@@ -0,0 +1,81 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.registration.DynamicMap;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.ChildCollection;
+import com.google.gerrit.extensions.restapi.IdString;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.gerrit.extensions.restapi.RestApiException;
+import com.google.gerrit.extensions.restapi.RestView;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectResource;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+
+@Singleton
+public class LabelsCollection implements ChildCollection<ProjectResource, LabelResource> {
+  private final Provider<ListLabels> list;
+  private final DynamicMap<RestView<LabelResource>> views;
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+
+  @Inject
+  LabelsCollection(
+      Provider<ListLabels> list,
+      DynamicMap<RestView<LabelResource>> views,
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend) {
+    this.list = list;
+    this.views = views;
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+  }
+
+  @Override
+  public RestView<ProjectResource> list() throws RestApiException {
+    return list.get();
+  }
+
+  @Override
+  public LabelResource parse(ProjectResource parent, IdString id)
+      throws AuthException, ResourceNotFoundException, PermissionBackendException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    permissionBackend
+        .currentUser()
+        .project(parent.getNameKey())
+        .check(ProjectPermission.READ_CONFIG);
+    LabelType labelType = parent.getProjectState().getConfig().getLabelSections().get(id.get());
+    if (labelType == null) {
+      throw new ResourceNotFoundException(id);
+    }
+    return new LabelResource(parent, labelType);
+  }
+
+  @Override
+  public DynamicMap<RestView<LabelResource>> views() {
+    return views;
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/ListLabels.java b/java/com/google/gerrit/server/restapi/project/ListLabels.java
new file mode 100644
index 0000000..19a8915
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/ListLabels.java
@@ -0,0 +1,91 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestReadView;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelDefinitionJson;
+import com.google.gerrit.server.project.ProjectResource;
+import com.google.gerrit.server.project.ProjectState;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Comparator;
+import java.util.List;
+import org.kohsuke.args4j.Option;
+
+public class ListLabels implements RestReadView<ProjectResource> {
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+
+  @Inject
+  public ListLabels(Provider<CurrentUser> user, PermissionBackend permissionBackend) {
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+  }
+
+  @Option(name = "--inherited", usage = "to include inherited label definitions")
+  private boolean inherited;
+
+  public ListLabels withInherited(boolean inherited) {
+    this.inherited = inherited;
+    return this;
+  }
+
+  @Override
+  public Response<List<LabelDefinitionInfo>> apply(ProjectResource rsrc)
+      throws AuthException, PermissionBackendException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    if (inherited) {
+      List<LabelDefinitionInfo> allLabels = new ArrayList<>();
+      for (ProjectState projectState : rsrc.getProjectState().treeInOrder()) {
+        try {
+          permissionBackend
+              .currentUser()
+              .project(projectState.getNameKey())
+              .check(ProjectPermission.READ_CONFIG);
+        } catch (AuthException e) {
+          throw new AuthException(projectState.getNameKey() + ": " + e.getMessage(), e);
+        }
+        allLabels.addAll(listLabels(projectState));
+      }
+      return Response.ok(allLabels);
+    }
+
+    permissionBackend.currentUser().project(rsrc.getNameKey()).check(ProjectPermission.READ_CONFIG);
+    return Response.ok(listLabels(rsrc.getProjectState()));
+  }
+
+  private List<LabelDefinitionInfo> listLabels(ProjectState projectState) {
+    Collection<LabelType> labelTypes = projectState.getConfig().getLabelSections().values();
+    List<LabelDefinitionInfo> labels = new ArrayList<>(labelTypes.size());
+    for (LabelType labelType : labelTypes) {
+      labels.add(LabelDefinitionJson.format(projectState.getNameKey(), labelType));
+    }
+    labels.sort(Comparator.comparing(l -> l.name));
+    return labels;
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/Module.java b/java/com/google/gerrit/server/restapi/project/Module.java
index de5661d..5b3ea30 100644
--- a/java/com/google/gerrit/server/restapi/project/Module.java
+++ b/java/com/google/gerrit/server/restapi/project/Module.java
@@ -19,6 +19,7 @@
 import static com.google.gerrit.server.project.CommitResource.COMMIT_KIND;
 import static com.google.gerrit.server.project.DashboardResource.DASHBOARD_KIND;
 import static com.google.gerrit.server.project.FileResource.FILE_KIND;
+import static com.google.gerrit.server.project.LabelResource.LABEL_KIND;
 import static com.google.gerrit.server.project.ProjectResource.PROJECT_KIND;
 import static com.google.gerrit.server.project.TagResource.TAG_KIND;
 
@@ -42,6 +43,7 @@
     DynamicMap.mapOf(binder(), FILE_KIND);
     DynamicMap.mapOf(binder(), COMMIT_KIND);
     DynamicMap.mapOf(binder(), TAG_KIND);
+    DynamicMap.mapOf(binder(), LABEL_KIND);
 
     DynamicSet.bind(binder(), GerritConfigListener.class).to(SetParent.class);
 
@@ -65,6 +67,13 @@
     child(PROJECT_KIND, "children").to(ChildProjectsCollection.class);
     get(CHILD_PROJECT_KIND).to(GetChildProject.class);
 
+    child(PROJECT_KIND, "labels").to(LabelsCollection.class);
+    create(LABEL_KIND).to(CreateLabel.class);
+    get(LABEL_KIND).to(GetLabel.class);
+    put(LABEL_KIND).to(SetLabel.class);
+    delete(LABEL_KIND).to(DeleteLabel.class);
+    postOnCollection(LABEL_KIND).to(PostLabels.class);
+
     get(PROJECT_KIND, "HEAD").to(GetHead.class);
     put(PROJECT_KIND, "HEAD").to(SetHead.class);
 
diff --git a/java/com/google/gerrit/server/restapi/project/PostLabels.java b/java/com/google/gerrit/server/restapi/project/PostLabels.java
new file mode 100644
index 0000000..8835359
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/PostLabels.java
@@ -0,0 +1,148 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.common.BatchLabelInput;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestCollectionModifyView;
+import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.git.meta.MetaDataUpdate;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectConfig;
+import com.google.gerrit.server.project.ProjectResource;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import java.util.Map.Entry;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+/** REST endpoint that allows to add, update and delete label definitions in a batch. */
+@Singleton
+public class PostLabels
+    implements RestCollectionModifyView<ProjectResource, LabelResource, BatchLabelInput> {
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+  private final MetaDataUpdate.User updateFactory;
+  private final ProjectConfig.Factory projectConfigFactory;
+  private final DeleteLabel deleteLabel;
+  private final CreateLabel createLabel;
+  private final SetLabel setLabel;
+  private final ProjectCache projectCache;
+
+  @Inject
+  public PostLabels(
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend,
+      MetaDataUpdate.User updateFactory,
+      ProjectConfig.Factory projectConfigFactory,
+      DeleteLabel deleteLabel,
+      CreateLabel createLabel,
+      SetLabel setLabel,
+      ProjectCache projectCache) {
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
+    this.projectConfigFactory = projectConfigFactory;
+    this.deleteLabel = deleteLabel;
+    this.createLabel = createLabel;
+    this.setLabel = setLabel;
+    this.projectCache = projectCache;
+  }
+
+  @Override
+  public Response<?> apply(ProjectResource rsrc, BatchLabelInput input)
+      throws AuthException, UnprocessableEntityException, PermissionBackendException, IOException,
+          ConfigInvalidException, BadRequestException, ResourceConflictException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    permissionBackend
+        .currentUser()
+        .project(rsrc.getNameKey())
+        .check(ProjectPermission.WRITE_CONFIG);
+
+    if (input == null) {
+      input = new BatchLabelInput();
+    }
+
+    try (MetaDataUpdate md = updateFactory.create(rsrc.getNameKey())) {
+      boolean dirty = false;
+
+      ProjectConfig config = projectConfigFactory.read(md);
+
+      if (input.delete != null && !input.delete.isEmpty()) {
+        for (String labelName : input.delete) {
+          if (!deleteLabel.deleteLabel(config, labelName.trim())) {
+            throw new UnprocessableEntityException(String.format("label %s not found", labelName));
+          }
+        }
+        dirty = true;
+      }
+
+      if (input.create != null && !input.create.isEmpty()) {
+        for (LabelDefinitionInput labelInput : input.create) {
+          if (labelInput.name == null || labelInput.name.trim().isEmpty()) {
+            throw new BadRequestException("label name is required for new label");
+          }
+          if (labelInput.commitMessage != null) {
+            throw new BadRequestException("commit message on label definition input not supported");
+          }
+          createLabel.createLabel(config, labelInput.name.trim(), labelInput);
+        }
+        dirty = true;
+      }
+
+      if (input.update != null && !input.update.isEmpty()) {
+        for (Entry<String, LabelDefinitionInput> e : input.update.entrySet()) {
+          LabelType labelType = config.getLabelSections().get(e.getKey().trim());
+          if (labelType == null) {
+            throw new UnprocessableEntityException(String.format("label %s not found", e.getKey()));
+          }
+          if (e.getValue().commitMessage != null) {
+            throw new BadRequestException("commit message on label definition input not supported");
+          }
+          setLabel.updateLabel(config, labelType, e.getValue());
+        }
+        dirty = true;
+      }
+
+      if (input.commitMessage != null) {
+        md.setMessage(Strings.emptyToNull(input.commitMessage.trim()));
+      } else {
+        md.setMessage("Update labels");
+      }
+
+      if (dirty) {
+        config.commit(md);
+        projectCache.evict(rsrc.getProjectState().getProject());
+      }
+    }
+
+    return Response.ok("");
+  }
+}
diff --git a/java/com/google/gerrit/server/restapi/project/PutConfig.java b/java/com/google/gerrit/server/restapi/project/PutConfig.java
index 696ac37..a0badd7 100644
--- a/java/com/google/gerrit/server/restapi/project/PutConfig.java
+++ b/java/com/google/gerrit/server/restapi/project/PutConfig.java
@@ -14,11 +14,17 @@
 
 package com.google.gerrit.server.restapi.project;
 
+import static com.google.gerrit.server.project.ProjectConfig.COMMENTLINK;
+import static com.google.gerrit.server.project.ProjectConfig.KEY_ENABLED;
+import static com.google.gerrit.server.project.ProjectConfig.KEY_LINK;
+import static com.google.gerrit.server.project.ProjectConfig.KEY_MATCH;
+
 import com.google.common.base.Joiner;
 import com.google.common.base.Strings;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.entities.BooleanProjectConfig;
 import com.google.gerrit.entities.Project;
+import com.google.gerrit.extensions.api.projects.CommentLinkInput;
 import com.google.gerrit.extensions.api.projects.ConfigInfo;
 import com.google.gerrit.extensions.api.projects.ConfigInput;
 import com.google.gerrit.extensions.api.projects.ConfigValue;
@@ -59,6 +65,7 @@
 import java.util.regex.Pattern;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
+import org.eclipse.jgit.lib.Config;
 
 @Singleton
 public class PutConfig implements RestModifyView<ProjectResource, ConfigInput> {
@@ -154,6 +161,10 @@
         setPluginConfigValues(projectState, projectConfig, input.pluginConfigValues);
       }
 
+      if (input.commentLinks != null) {
+        updateCommentLinks(projectConfig, input.commentLinks);
+      }
+
       md.setMessage("Modified project settings\n");
       try {
         projectConfig.commit(md);
@@ -278,6 +289,25 @@
     }
   }
 
+  private void updateCommentLinks(
+      ProjectConfig projectConfig, Map<String, CommentLinkInput> input) {
+    for (Map.Entry<String, CommentLinkInput> e : input.entrySet()) {
+      String name = e.getKey();
+      CommentLinkInput value = e.getValue();
+      if (value != null) {
+        // Add or update the commentlink section
+        Config cfg = new Config();
+        cfg.setString(COMMENTLINK, name, KEY_MATCH, value.match);
+        cfg.setString(COMMENTLINK, name, KEY_LINK, value.link);
+        cfg.setBoolean(COMMENTLINK, name, KEY_ENABLED, value.enabled == null || value.enabled);
+        projectConfig.addCommentLinkSection(ProjectConfig.buildCommentLink(cfg, name, false));
+      } else {
+        // Delete the commentlink section
+        projectConfig.removeCommentLinkSection(name);
+      }
+    }
+  }
+
   private static void validateProjectConfigEntryIsEditable(
       ProjectConfigEntry projectConfigEntry,
       ProjectState projectState,
diff --git a/java/com/google/gerrit/server/restapi/project/QueryProjects.java b/java/com/google/gerrit/server/restapi/project/QueryProjects.java
index 7066d9a..e4f7df5 100644
--- a/java/com/google/gerrit/server/restapi/project/QueryProjects.java
+++ b/java/com/google/gerrit/server/restapi/project/QueryProjects.java
@@ -31,6 +31,7 @@
 import com.google.gerrit.server.query.project.ProjectQueryBuilder;
 import com.google.gerrit.server.query.project.ProjectQueryProcessor;
 import com.google.inject.Inject;
+import com.google.inject.Provider;
 import java.util.ArrayList;
 import java.util.List;
 import org.kohsuke.args4j.Option;
@@ -38,7 +39,7 @@
 public class QueryProjects implements RestReadView<TopLevelResource> {
   private final ProjectIndexCollection indexes;
   private final ProjectQueryBuilder queryBuilder;
-  private final ProjectQueryProcessor queryProcessor;
+  private final Provider<ProjectQueryProcessor> queryProcessorProvider;
   private final ProjectJson json;
 
   private String query;
@@ -78,11 +79,11 @@
   protected QueryProjects(
       ProjectIndexCollection indexes,
       ProjectQueryBuilder queryBuilder,
-      ProjectQueryProcessor queryProcessor,
+      Provider<ProjectQueryProcessor> queryProcessorProvider,
       ProjectJson json) {
     this.indexes = indexes;
     this.queryBuilder = queryBuilder;
-    this.queryProcessor = queryProcessor;
+    this.queryProcessorProvider = queryProcessorProvider;
     this.json = json;
   }
 
@@ -102,6 +103,8 @@
       throw new MethodNotAllowedException("no project index");
     }
 
+    ProjectQueryProcessor queryProcessor = queryProcessorProvider.get();
+
     if (start != 0) {
       queryProcessor.setStart(start);
     }
diff --git a/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java b/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
index bac71de..8879fae 100644
--- a/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
+++ b/java/com/google/gerrit/server/restapi/project/SetDefaultDashboard.java
@@ -24,9 +24,11 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestApiException;
 import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.server.git.meta.MetaDataUpdate;
 import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
 import com.google.gerrit.server.permissions.ProjectPermission;
 import com.google.gerrit.server.project.DashboardResource;
 import com.google.gerrit.server.project.ProjectCache;
@@ -34,6 +36,7 @@
 import com.google.gerrit.server.project.ProjectResource;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
+import java.io.IOException;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
 import org.kohsuke.args4j.Option;
@@ -67,7 +70,7 @@
 
   @Override
   public Response<DashboardInfo> apply(DashboardResource rsrc, SetDashboardInput input)
-      throws Exception {
+      throws RestApiException, IOException, PermissionBackendException {
     if (input == null) {
       input = new SetDashboardInput(); // Delete would set input to null.
     }
diff --git a/java/com/google/gerrit/server/restapi/project/SetHead.java b/java/com/google/gerrit/server/restapi/project/SetHead.java
index 42c0559..946695e 100644
--- a/java/com/google/gerrit/server/restapi/project/SetHead.java
+++ b/java/com/google/gerrit/server/restapi/project/SetHead.java
@@ -25,6 +25,7 @@
 import com.google.gerrit.extensions.restapi.Response;
 import com.google.gerrit.extensions.restapi.RestModifyView;
 import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
+import com.google.gerrit.git.LockFailureException;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.extensions.events.AbstractNoNotifyEvent;
 import com.google.gerrit.server.git.GitRepositoryManager;
@@ -96,9 +97,10 @@
           case FORCED:
           case NEW:
             break;
+          case LOCK_FAILURE:
+            throw new LockFailureException("Setting HEAD failed", u);
           case FAST_FORWARD:
           case IO_FAILURE:
-          case LOCK_FAILURE:
           case NOT_ATTEMPTED:
           case REJECTED:
           case REJECTED_CURRENT_BRANCH:
diff --git a/java/com/google/gerrit/server/restapi/project/SetLabel.java b/java/com/google/gerrit/server/restapi/project/SetLabel.java
new file mode 100644
index 0000000..824b4ed
--- /dev/null
+++ b/java/com/google/gerrit/server/restapi/project/SetLabel.java
@@ -0,0 +1,222 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.restapi.project;
+
+import com.google.common.base.Strings;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.Response;
+import com.google.gerrit.extensions.restapi.RestModifyView;
+import com.google.gerrit.server.CurrentUser;
+import com.google.gerrit.server.git.meta.MetaDataUpdate;
+import com.google.gerrit.server.permissions.PermissionBackend;
+import com.google.gerrit.server.permissions.PermissionBackendException;
+import com.google.gerrit.server.permissions.ProjectPermission;
+import com.google.gerrit.server.project.LabelDefinitionJson;
+import com.google.gerrit.server.project.LabelResource;
+import com.google.gerrit.server.project.ProjectCache;
+import com.google.gerrit.server.project.ProjectConfig;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import com.google.inject.Singleton;
+import java.io.IOException;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+
+@Singleton
+public class SetLabel implements RestModifyView<LabelResource, LabelDefinitionInput> {
+  private final Provider<CurrentUser> user;
+  private final PermissionBackend permissionBackend;
+  private final MetaDataUpdate.User updateFactory;
+  private final ProjectConfig.Factory projectConfigFactory;
+  private final ProjectCache projectCache;
+
+  @Inject
+  public SetLabel(
+      Provider<CurrentUser> user,
+      PermissionBackend permissionBackend,
+      MetaDataUpdate.User updateFactory,
+      ProjectConfig.Factory projectConfigFactory,
+      ProjectCache projectCache) {
+    this.user = user;
+    this.permissionBackend = permissionBackend;
+    this.updateFactory = updateFactory;
+    this.projectConfigFactory = projectConfigFactory;
+    this.projectCache = projectCache;
+  }
+
+  @Override
+  public Response<LabelDefinitionInfo> apply(LabelResource rsrc, LabelDefinitionInput input)
+      throws AuthException, BadRequestException, ResourceConflictException,
+          PermissionBackendException, IOException, ConfigInvalidException {
+    if (!user.get().isIdentifiedUser()) {
+      throw new AuthException("Authentication required");
+    }
+
+    permissionBackend
+        .currentUser()
+        .project(rsrc.getProject().getNameKey())
+        .check(ProjectPermission.WRITE_CONFIG);
+
+    if (input == null) {
+      input = new LabelDefinitionInput();
+    }
+
+    LabelType labelType = rsrc.getLabelType();
+
+    try (MetaDataUpdate md = updateFactory.create(rsrc.getProject().getNameKey())) {
+      ProjectConfig config = projectConfigFactory.read(md);
+
+      if (updateLabel(config, labelType, input)) {
+        if (input.commitMessage != null) {
+          md.setMessage(Strings.emptyToNull(input.commitMessage.trim()));
+        } else {
+          md.setMessage("Update label");
+        }
+
+        config.commit(md);
+        projectCache.evict(rsrc.getProject().getProjectState().getProject());
+      }
+    }
+    return Response.ok(LabelDefinitionJson.format(rsrc.getProject().getNameKey(), labelType));
+  }
+
+  /**
+   * Updates the given label.
+   *
+   * @param config the project config
+   * @param labelType the label type that should be updated
+   * @param input the input that describes the label update
+   * @return whether the label type was modified
+   * @throws BadRequestException if there was invalid data in the input
+   * @throws ResourceConflictException if the update cannot be applied due to a conflict
+   */
+  public boolean updateLabel(ProjectConfig config, LabelType labelType, LabelDefinitionInput input)
+      throws BadRequestException, ResourceConflictException {
+    boolean dirty = false;
+
+    config.getLabelSections().remove(labelType.getName());
+
+    if (input.name != null) {
+      String newName = input.name.trim();
+      if (newName.isEmpty()) {
+        throw new BadRequestException("name cannot be empty");
+      }
+      if (!newName.equals(labelType.getName())) {
+        if (config.getLabelSections().containsKey(newName)) {
+          throw new ResourceConflictException(String.format("name %s already in use", newName));
+        }
+
+        for (String labelName : config.getLabelSections().keySet()) {
+          if (labelName.equalsIgnoreCase(newName)) {
+            throw new ResourceConflictException(
+                String.format("name %s conflicts with existing label %s", newName, labelName));
+          }
+        }
+
+        try {
+          labelType.setName(newName);
+        } catch (IllegalArgumentException e) {
+          throw new BadRequestException("invalid name: " + input.name, e);
+        }
+        dirty = true;
+      }
+    }
+
+    if (input.function != null) {
+      if (input.function.trim().isEmpty()) {
+        throw new BadRequestException("function cannot be empty");
+      }
+      labelType.setFunction(LabelDefinitionInputParser.parseFunction(input.function));
+      dirty = true;
+    }
+
+    if (input.values != null) {
+      if (input.values.isEmpty()) {
+        throw new BadRequestException("values cannot be empty");
+      }
+      labelType.setValues(LabelDefinitionInputParser.parseValues(input.values));
+      dirty = true;
+    }
+
+    if (input.defaultValue != null) {
+      labelType.setDefaultValue(
+          LabelDefinitionInputParser.parseDefaultValue(labelType, input.defaultValue));
+      dirty = true;
+    }
+
+    if (input.branches != null) {
+      labelType.setRefPatterns(LabelDefinitionInputParser.parseBranches(input.branches));
+      dirty = true;
+    }
+
+    if (input.canOverride != null) {
+      labelType.setCanOverride(input.canOverride);
+      dirty = true;
+    }
+
+    if (input.copyAnyScore != null) {
+      labelType.setCopyAnyScore(input.copyAnyScore);
+      dirty = true;
+    }
+
+    if (input.copyMinScore != null) {
+      labelType.setCopyMinScore(input.copyMinScore);
+      dirty = true;
+    }
+
+    if (input.copyMaxScore != null) {
+      labelType.setCopyMaxScore(input.copyMaxScore);
+      dirty = true;
+    }
+
+    if (input.copyAllScoresIfNoChange != null) {
+      labelType.setCopyAllScoresIfNoChange(input.copyAllScoresIfNoChange);
+    }
+
+    if (input.copyAllScoresIfNoCodeChange != null) {
+      labelType.setCopyAllScoresIfNoCodeChange(input.copyAllScoresIfNoCodeChange);
+      dirty = true;
+    }
+
+    if (input.copyAllScoresOnTrivialRebase != null) {
+      labelType.setCopyAllScoresOnTrivialRebase(input.copyAllScoresOnTrivialRebase);
+      dirty = true;
+    }
+
+    if (input.copyAllScoresOnMergeFirstParentUpdate != null) {
+      labelType.setCopyAllScoresOnMergeFirstParentUpdate(
+          input.copyAllScoresOnMergeFirstParentUpdate);
+      dirty = true;
+    }
+
+    if (input.allowPostSubmit != null) {
+      labelType.setAllowPostSubmit(input.allowPostSubmit);
+      dirty = true;
+    }
+
+    if (input.ignoreSelfApproval != null) {
+      labelType.setIgnoreSelfApproval(input.ignoreSelfApproval);
+      dirty = true;
+    }
+
+    config.getLabelSections().put(labelType.getName(), labelType);
+
+    return dirty;
+  }
+}
diff --git a/java/com/google/gerrit/server/submit/MergeOp.java b/java/com/google/gerrit/server/submit/MergeOp.java
index a06027a..75ae62d 100644
--- a/java/com/google/gerrit/server/submit/MergeOp.java
+++ b/java/com/google/gerrit/server/submit/MergeOp.java
@@ -91,7 +91,6 @@
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import java.util.Set;
 import org.eclipse.jgit.errors.ConfigInvalidException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
@@ -248,7 +247,6 @@
   private Set<Project.NameKey> allProjects;
   private boolean dryrun;
   private TopicMetrics topicMetrics;
-  private String traceId;
 
   @Inject
   MergeOp(
@@ -504,7 +502,7 @@
               try {
                 integrateIntoHistory(cs);
               } catch (IntegrationException e) {
-                logger.atSevere().withCause(e).log("Error from integrateIntoHistory");
+                logger.atWarning().withCause(e).log("Error from integrateIntoHistory");
                 throw new ResourceConflictException(e.getMessage(), e);
               }
               return null;
@@ -518,9 +516,6 @@
                     retryHelper
                         .getDefaultTimeout(ActionType.CHANGE_UPDATE)
                         .multipliedBy(cs.projects().size()))
-                .caller(getClass())
-                .retryWithTrace(t -> !(t instanceof RestApiException))
-                .onAutoTrace(traceId -> this.traceId = traceId)
                 .build());
 
         if (projects > 1) {
@@ -541,10 +536,6 @@
     }
   }
 
-  public Optional<String> getTraceId() {
-    return Optional.ofNullable(traceId);
-  }
-
   private void openRepoManager() {
     if (orm != null) {
       orm.close();
diff --git a/java/com/google/gerrit/server/submit/MergeOpRepoManager.java b/java/com/google/gerrit/server/submit/MergeOpRepoManager.java
index c2577e7..9a7ced5 100644
--- a/java/com/google/gerrit/server/submit/MergeOpRepoManager.java
+++ b/java/com/google/gerrit/server/submit/MergeOpRepoManager.java
@@ -42,10 +42,9 @@
 import java.util.Map;
 import java.util.Objects;
 import org.eclipse.jgit.errors.RepositoryNotFoundException;
-import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.ObjectReader;
-import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevFlag;
 import org.eclipse.jgit.revwalk.RevSort;
@@ -130,19 +129,17 @@
   }
 
   public static class OpenBranch {
-    final RefUpdate update;
     final CodeReviewCommit oldTip;
     MergeTip mergeTip;
 
     OpenBranch(OpenRepo or, BranchNameKey name) throws IntegrationException {
       try {
-        update = or.repo.updateRef(name.branch());
-        if (update.getOldObjectId() != null) {
-          oldTip = or.rw.parseCommit(update.getOldObjectId());
+        Ref ref = or.getRepo().exactRef(name.branch());
+        if (ref != null) {
+          oldTip = or.rw.parseCommit(ref.getObjectId());
         } else if (Objects.equals(or.repo.getFullBranch(), name.branch())
             || Objects.equals(RefNames.REFS_CONFIG, name.branch())) {
           oldTip = null;
-          update.setExpectedOldObjectId(ObjectId.zeroId());
         } else {
           throw new IntegrationException(
               "The destination branch " + name + " does not exist anymore.");
diff --git a/java/com/google/gerrit/server/update/BatchUpdate.java b/java/com/google/gerrit/server/update/BatchUpdate.java
index ce16706..e240f6a 100644
--- a/java/com/google/gerrit/server/update/BatchUpdate.java
+++ b/java/com/google/gerrit/server/update/BatchUpdate.java
@@ -128,23 +128,23 @@
 
     try {
       List<ListenableFuture<?>> indexFutures = new ArrayList<>();
-      List<ChangesHandle> handles = new ArrayList<>(updates.size());
+      List<ChangesHandle> changesHandles = new ArrayList<>(updates.size());
       try {
         for (BatchUpdate u : updates) {
           u.executeUpdateRepo();
         }
         listener.afterUpdateRepos();
         for (BatchUpdate u : updates) {
-          handles.add(u.executeChangeOps(dryrun));
+          changesHandles.add(u.executeChangeOps(dryrun));
         }
-        for (ChangesHandle h : handles) {
+        for (ChangesHandle h : changesHandles) {
           h.execute();
           indexFutures.addAll(h.startIndexFutures());
         }
         listener.afterUpdateRefs();
         listener.afterUpdateChanges();
       } finally {
-        for (ChangesHandle h : handles) {
+        for (ChangesHandle h : changesHandles) {
           h.close();
         }
       }
diff --git a/java/com/google/gerrit/server/update/RetryHelper.java b/java/com/google/gerrit/server/update/RetryHelper.java
index bea3867..4f9a67c 100644
--- a/java/com/google/gerrit/server/update/RetryHelper.java
+++ b/java/com/google/gerrit/server/update/RetryHelper.java
@@ -32,10 +32,9 @@
 import com.google.common.collect.Maps;
 import com.google.common.flogger.FluentLogger;
 import com.google.gerrit.common.Nullable;
+import com.google.gerrit.exceptions.StorageException;
 import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.git.LockFailureException;
-import com.google.gerrit.metrics.Counter1;
-import com.google.gerrit.metrics.Counter2;
+import com.google.gerrit.metrics.Counter3;
 import com.google.gerrit.metrics.Description;
 import com.google.gerrit.metrics.Field;
 import com.google.gerrit.metrics.MetricMaker;
@@ -75,7 +74,9 @@
     CHANGE_UPDATE,
     GROUP_UPDATE,
     INDEX_QUERY,
-    PLUGIN_UPDATE
+    PLUGIN_UPDATE,
+    REST_READ_REQUEST,
+    REST_WRITE_REQUEST,
   }
 
   /**
@@ -100,7 +101,7 @@
     @Nullable
     abstract Duration timeout();
 
-    abstract Optional<Class<?>> caller();
+    abstract Optional<String> caller();
 
     abstract Optional<Predicate<Throwable>> retryWithTrace();
 
@@ -112,7 +113,7 @@
 
       public abstract Builder timeout(Duration timeout);
 
-      public abstract Builder caller(Class<?> caller);
+      public abstract Builder caller(String caller);
 
       public abstract Builder retryWithTrace(Predicate<Throwable> exceptionPredicate);
 
@@ -125,15 +126,28 @@
   @VisibleForTesting
   @Singleton
   public static class Metrics {
-    final Counter1<ActionType> attemptCounts;
-    final Counter1<ActionType> timeoutCount;
-    final Counter2<ActionType, String> autoRetryCount;
-    final Counter2<ActionType, String> failuresOnAutoRetryCount;
+    final Counter3<ActionType, String, String> attemptCounts;
+    final Counter3<ActionType, String, String> timeoutCount;
+    final Counter3<ActionType, String, String> autoRetryCount;
+    final Counter3<ActionType, String, String> failuresOnAutoRetryCount;
 
     @Inject
     Metrics(MetricMaker metricMaker) {
       Field<ActionType> actionTypeField =
           Field.ofEnum(ActionType.class, "action_type", Metadata.Builder::actionType).build();
+      Field<String> operationNameField =
+          Field.ofString("operation_name", Metadata.Builder::operationName)
+              .description("The name of the operation that was retried.")
+              .build();
+      Field<String> lastAttemptCauseField =
+          Field.ofString("cause", Metadata.Builder::cause)
+              .description("The cause for the last attempt.")
+              .build();
+      Field<String> causeField =
+          Field.ofString("cause", Metadata.Builder::cause)
+              .description("The cause for the retry.")
+              .build();
+
       attemptCounts =
           metricMaker.newCounter(
               "action/retry_attempt_count",
@@ -142,7 +156,9 @@
                           + " (0 == single attempt, no retry)")
                   .setCumulative()
                   .setUnit("attempts"),
-              actionTypeField);
+              actionTypeField,
+              operationNameField,
+              lastAttemptCauseField);
       timeoutCount =
           metricMaker.newCounter(
               "action/retry_timeout_count",
@@ -150,7 +166,9 @@
                       "Number of action executions of RetryHelper that ultimately timed out")
                   .setCumulative()
                   .setUnit("timeouts"),
-              actionTypeField);
+              actionTypeField,
+              operationNameField,
+              lastAttemptCauseField);
       autoRetryCount =
           metricMaker.newCounter(
               "action/auto_retry_count",
@@ -158,9 +176,8 @@
                   .setCumulative()
                   .setUnit("retries"),
               actionTypeField,
-              Field.ofString("operation_name", Metadata.Builder::operationName)
-                  .description("The name of the operation that was retried.")
-                  .build());
+              operationNameField,
+              causeField);
       failuresOnAutoRetryCount =
           metricMaker.newCounter(
               "action/failures_on_auto_retry_count",
@@ -168,9 +185,8 @@
                   .setCumulative()
                   .setUnit("failures"),
               actionTypeField,
-              Field.ofString("operation_name", Metadata.Builder::operationName)
-                  .description("The name of the operation that was retried.")
-                  .build());
+              operationNameField,
+              causeField);
     }
   }
 
@@ -270,15 +286,7 @@
       throws RestApiException, UpdateException {
     try {
       return execute(
-          ActionType.CHANGE_UPDATE,
-          () -> changeAction.call(updateFactory),
-          opts,
-          t -> {
-            if (t instanceof UpdateException) {
-              t = t.getCause();
-            }
-            return t instanceof LockFailureException;
-          });
+          ActionType.CHANGE_UPDATE, () -> changeAction.call(updateFactory), opts, t -> false);
     } catch (Throwable t) {
       Throwables.throwIfUnchecked(t);
       Throwables.throwIfInstanceOf(t, UpdateException.class);
@@ -327,14 +335,15 @@
                 if (retryWithTraceOnFailure
                     && opts.retryWithTrace().isPresent()
                     && opts.retryWithTrace().get().test(t)) {
-                  String caller = opts.caller().map(Class::getSimpleName).orElse("N/A");
+                  String caller = opts.caller().orElse("N/A");
+                  String cause = formatCause(t);
                   if (!traceContext.isTracing()) {
                     String traceId = "retry-on-failure-" + new RequestId();
                     traceContext.addTag(RequestId.Type.TRACE_ID, traceId).forceLogging();
                     opts.onAutoTrace().ifPresent(c -> c.accept(traceId));
                     logger.atFine().withCause(t).log(
                         "AutoRetry: %s failed, retry with tracing enabled", caller);
-                    metrics.autoRetryCount.increment(actionType, caller);
+                    metrics.autoRetryCount.increment(actionType, caller, cause);
                     return true;
                   }
 
@@ -343,39 +352,71 @@
                   // differs from the failure that triggered the retry.
                   logger.atFine().withCause(t).log(
                       "AutoRetry: auto-retry of %s has failed", caller);
-                  metrics.failuresOnAutoRetryCount.increment(actionType, caller);
+                  metrics.failuresOnAutoRetryCount.increment(actionType, caller, cause);
                   return false;
                 }
 
                 return false;
               });
       retryerBuilder.withRetryListener(listener);
-      return executeWithTimeoutCount(actionType, action, retryerBuilder.build());
+      return executeWithTimeoutCount(actionType, action, opts, retryerBuilder.build());
     } finally {
       if (listener.getAttemptCount() > 1) {
         logger.atFine().log("%s was attempted %d times", actionType, listener.getAttemptCount());
-        metrics.attemptCounts.incrementBy(actionType, listener.getAttemptCount() - 1);
+        metrics.attemptCounts.incrementBy(
+            actionType,
+            opts.caller().orElse("N/A"),
+            listener.getCause().map(this::formatCause).orElse("_unknown"),
+            listener.getAttemptCount() - 1);
       }
     }
   }
 
+  public String formatCause(Throwable t) {
+    while ((t instanceof UpdateException
+            || t instanceof StorageException
+            || t instanceof ExecutionException)
+        && t.getCause() != null) {
+      t = t.getCause();
+    }
+
+    Optional<String> formattedCause = getFormattedCauseFromHooks(t);
+    if (formattedCause.isPresent()) {
+      return formattedCause.get();
+    }
+
+    return t.getClass().getSimpleName();
+  }
+
+  private Optional<String> getFormattedCauseFromHooks(Throwable t) {
+    return exceptionHooks.stream()
+        .map(h -> h.formatCause(t))
+        .filter(Optional::isPresent)
+        .map(Optional::get)
+        .findFirst();
+  }
+
   /**
    * Executes an action and records the timeout as metric.
    *
    * @param actionType the type of the action
    * @param action the action which should be executed and retried on failure
+   * @param opts options for retrying the action on failure
    * @param retryer the retryer
    * @return the result of executing the action
    * @throws Throwable any error or exception that made the action fail, callers are expected to
    *     catch and inspect this Throwable to decide carefully whether it should be re-thrown
    */
-  private <T> T executeWithTimeoutCount(ActionType actionType, Action<T> action, Retryer<T> retryer)
-      throws Throwable {
+  private <T> T executeWithTimeoutCount(
+      ActionType actionType, Action<T> action, Options opts, Retryer<T> retryer) throws Throwable {
     try {
       return retryer.call(action::call);
     } catch (ExecutionException | RetryException e) {
       if (e instanceof RetryException) {
-        metrics.timeoutCount.increment(actionType);
+        metrics.timeoutCount.increment(
+            actionType,
+            opts.caller().orElse("N/A"),
+            e.getCause() != null ? formatCause(e.getCause()) : "_unknown");
       }
       if (e.getCause() != null) {
         throw e.getCause();
@@ -407,18 +448,27 @@
 
   private static class MetricListener implements RetryListener {
     private long attemptCount;
+    private Optional<Throwable> cause;
 
     MetricListener() {
       attemptCount = 1;
+      cause = Optional.empty();
     }
 
     @Override
     public <V> void onRetry(Attempt<V> attempt) {
       attemptCount = attempt.getAttemptNumber();
+      if (attempt.hasException()) {
+        cause = Optional.of(attempt.getExceptionCause());
+      }
     }
 
     long getAttemptCount() {
       return attemptCount;
     }
+
+    Optional<Throwable> getCause() {
+      return cause;
+    }
   }
 }
diff --git a/java/com/google/gerrit/server/update/RetryingRestCollectionModifyView.java b/java/com/google/gerrit/server/update/RetryingRestCollectionModifyView.java
deleted file mode 100644
index 96c2ed3..0000000
--- a/java/com/google/gerrit/server/update/RetryingRestCollectionModifyView.java
+++ /dev/null
@@ -1,58 +0,0 @@
-// Copyright (C) 2018 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.server.update;
-
-import com.google.common.base.Throwables;
-import com.google.gerrit.extensions.restapi.AuthException;
-import com.google.gerrit.extensions.restapi.BadRequestException;
-import com.google.gerrit.extensions.restapi.ResourceConflictException;
-import com.google.gerrit.extensions.restapi.Response;
-import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.extensions.restapi.RestCollectionModifyView;
-import com.google.gerrit.extensions.restapi.RestResource;
-import java.util.concurrent.atomic.AtomicReference;
-
-public abstract class RetryingRestCollectionModifyView<
-        P extends RestResource, C extends RestResource, I, O>
-    implements RestCollectionModifyView<P, C, I> {
-  private final RetryHelper retryHelper;
-
-  protected RetryingRestCollectionModifyView(RetryHelper retryHelper) {
-    this.retryHelper = retryHelper;
-  }
-
-  @Override
-  public final Response<O> apply(P parentResource, I input)
-      throws AuthException, BadRequestException, ResourceConflictException, Exception {
-    AtomicReference<String> traceId = new AtomicReference<>(null);
-    try {
-      RetryHelper.Options retryOptions =
-          RetryHelper.options()
-              .caller(getClass())
-              .retryWithTrace(t -> !(t instanceof RestApiException))
-              .onAutoTrace(traceId::set)
-              .build();
-      return retryHelper
-          .execute((updateFactory) -> applyImpl(updateFactory, parentResource, input), retryOptions)
-          .traceId(traceId.get());
-    } catch (Exception e) {
-      Throwables.throwIfInstanceOf(e, RestApiException.class);
-      return Response.<O>internalServerError(e).traceId(traceId.get());
-    }
-  }
-
-  protected abstract Response<O> applyImpl(
-      BatchUpdate.Factory updateFactory, P parentResource, I input) throws Exception;
-}
diff --git a/java/com/google/gerrit/server/update/RetryingRestModifyView.java b/java/com/google/gerrit/server/update/RetryingRestModifyView.java
deleted file mode 100644
index 275dc55..0000000
--- a/java/com/google/gerrit/server/update/RetryingRestModifyView.java
+++ /dev/null
@@ -1,53 +0,0 @@
-// Copyright (C) 2017 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package com.google.gerrit.server.update;
-
-import com.google.common.base.Throwables;
-import com.google.gerrit.extensions.restapi.Response;
-import com.google.gerrit.extensions.restapi.RestApiException;
-import com.google.gerrit.extensions.restapi.RestModifyView;
-import com.google.gerrit.extensions.restapi.RestResource;
-import java.util.concurrent.atomic.AtomicReference;
-
-public abstract class RetryingRestModifyView<R extends RestResource, I, O>
-    implements RestModifyView<R, I> {
-  private final RetryHelper retryHelper;
-
-  protected RetryingRestModifyView(RetryHelper retryHelper) {
-    this.retryHelper = retryHelper;
-  }
-
-  @Override
-  public final Response<O> apply(R resource, I input) throws RestApiException {
-    AtomicReference<String> traceId = new AtomicReference<>(null);
-    try {
-      RetryHelper.Options retryOptions =
-          RetryHelper.options()
-              .caller(getClass())
-              .retryWithTrace(t -> !(t instanceof RestApiException))
-              .onAutoTrace(traceId::set)
-              .build();
-      return retryHelper
-          .execute((updateFactory) -> applyImpl(updateFactory, resource, input), retryOptions)
-          .traceId(traceId.get());
-    } catch (Exception e) {
-      Throwables.throwIfInstanceOf(e, RestApiException.class);
-      return Response.<O>internalServerError(e).traceId(traceId.get());
-    }
-  }
-
-  protected abstract Response<O> applyImpl(BatchUpdate.Factory updateFactory, R resource, I input)
-      throws Exception;
-}
diff --git a/java/com/google/gerrit/sshd/BUILD b/java/com/google/gerrit/sshd/BUILD
index bc9a0ee..f567a3a 100644
--- a/java/com/google/gerrit/sshd/BUILD
+++ b/java/com/google/gerrit/sshd/BUILD
@@ -32,7 +32,6 @@
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
         "//lib/bouncycastle:bcprov-neverlink",
-        "//lib/commons:codec",
         "//lib/dropwizard:dropwizard-core",
         "//lib/flogger:api",
         "//lib/guice",
diff --git a/java/com/google/gerrit/sshd/DatabasePubKeyAuth.java b/java/com/google/gerrit/sshd/DatabasePubKeyAuth.java
index 6c0f3af..916775d 100644
--- a/java/com/google/gerrit/sshd/DatabasePubKeyAuth.java
+++ b/java/com/google/gerrit/sshd/DatabasePubKeyAuth.java
@@ -19,6 +19,7 @@
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.flogger.FluentLogger;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.common.FileUtil;
 import com.google.gerrit.server.IdentifiedUser;
 import com.google.gerrit.server.PeerDaemonUser;
@@ -39,7 +40,6 @@
 import java.util.HashSet;
 import java.util.Locale;
 import java.util.Set;
-import org.apache.commons.codec.binary.Base64;
 import org.apache.sshd.common.SshException;
 import org.apache.sshd.common.keyprovider.KeyPairProvider;
 import org.apache.sshd.common.util.buffer.ByteArrayBuffer;
@@ -198,7 +198,8 @@
           }
 
           try {
-            byte[] bin = Base64.decodeBase64(line.getBytes(ISO_8859_1));
+            byte[] bin =
+                BaseEncoding.base64().decode(new String(line.getBytes(ISO_8859_1), ISO_8859_1));
             keys.add(new ByteArrayBuffer(bin).getRawPublicKey());
           } catch (RuntimeException | SshException e) {
             logBadKey(path, line, e);
diff --git a/java/com/google/gerrit/sshd/SshUtil.java b/java/com/google/gerrit/sshd/SshUtil.java
index 39366f0..eac9737 100644
--- a/java/com/google/gerrit/sshd/SshUtil.java
+++ b/java/com/google/gerrit/sshd/SshUtil.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.sshd;
 
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.CurrentUser;
 import com.google.gerrit.server.IdentifiedUser;
@@ -28,12 +29,10 @@
 import java.security.interfaces.DSAPublicKey;
 import java.security.interfaces.RSAPublicKey;
 import java.security.spec.InvalidKeySpecException;
-import org.apache.commons.codec.binary.Base64;
 import org.apache.sshd.common.SshException;
 import org.apache.sshd.common.keyprovider.KeyPairProvider;
 import org.apache.sshd.common.util.buffer.ByteArrayBuffer;
 import org.apache.sshd.server.session.ServerSession;
-import org.eclipse.jgit.lib.Constants;
 
 /** Utilities to support SSH operations. */
 public class SshUtil {
@@ -53,7 +52,7 @@
       if (s == null) {
         throw new InvalidKeySpecException("No key string");
       }
-      final byte[] bin = Base64.decodeBase64(Constants.encodeASCII(s));
+      final byte[] bin = BaseEncoding.base64().decode(s);
       return new ByteArrayBuffer(bin).getRawPublicKey();
     } catch (RuntimeException | SshException e) {
       throw new InvalidKeySpecException("Cannot parse key", e);
@@ -91,8 +90,7 @@
       }
 
       final PublicKey key =
-          new ByteArrayBuffer(Base64.decodeBase64(Constants.encodeASCII(strBuf.toString())))
-              .getRawPublicKey();
+          new ByteArrayBuffer(BaseEncoding.base64().decode(strBuf.toString())).getRawPublicKey();
       if (key instanceof RSAPublicKey) {
         strBuf.insert(0, KeyPairProvider.SSH_RSA + " ");
 
diff --git a/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java b/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
index 9f420ed..17f80c0 100644
--- a/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
+++ b/java/com/google/gerrit/sshd/commands/CreateGroupCommand.java
@@ -119,7 +119,8 @@
     }
   }
 
-  private GroupResource createGroup() throws Exception {
+  private GroupResource createGroup()
+      throws RestApiException, IOException, ConfigInvalidException, PermissionBackendException {
     GroupInput input = new GroupInput();
     input.description = groupDescription;
     input.visibleToAll = visibleToAll;
diff --git a/java/com/google/gerrit/sshd/commands/SequenceCommandsModule.java b/java/com/google/gerrit/sshd/commands/SequenceCommandsModule.java
new file mode 100644
index 0000000..e716240
--- /dev/null
+++ b/java/com/google/gerrit/sshd/commands/SequenceCommandsModule.java
@@ -0,0 +1,32 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.sshd.commands;
+
+import com.google.gerrit.sshd.CommandModule;
+import com.google.gerrit.sshd.CommandName;
+import com.google.gerrit.sshd.Commands;
+import com.google.gerrit.sshd.DispatchCommandProvider;
+
+public class SequenceCommandsModule extends CommandModule {
+
+  @Override
+  protected void configure() {
+    CommandName gerrit = Commands.named("gerrit");
+    CommandName sequence = Commands.named(gerrit, "sequence");
+    command(sequence).toProvider(new DispatchCommandProvider(sequence));
+    command(sequence, SequenceSetCommand.class);
+    command(sequence, SequenceShowCommand.class);
+  }
+}
diff --git a/java/com/google/gerrit/sshd/commands/SequenceSetCommand.java b/java/com/google/gerrit/sshd/commands/SequenceSetCommand.java
new file mode 100644
index 0000000..197d61c
--- /dev/null
+++ b/java/com/google/gerrit/sshd/commands/SequenceSetCommand.java
@@ -0,0 +1,56 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.sshd.commands;
+
+import com.google.gerrit.common.data.GlobalCapability;
+import com.google.gerrit.extensions.annotations.RequiresCapability;
+import com.google.gerrit.server.notedb.Sequences;
+import com.google.gerrit.sshd.CommandMetaData;
+import com.google.gerrit.sshd.SshCommand;
+import com.google.inject.Inject;
+import org.kohsuke.args4j.Argument;
+
+/** Set sequence value. */
+@RequiresCapability(GlobalCapability.ADMINISTRATE_SERVER)
+@CommandMetaData(name = "set", description = "Set the sequence value")
+final class SequenceSetCommand extends SshCommand {
+  @Argument(index = 0, metaVar = "NAME", required = true, usage = "sequence name")
+  private String name;
+
+  @Argument(index = 1, metaVar = "VALUE", required = true, usage = "sequence value")
+  private int value;
+
+  @Inject Sequences sequences;
+
+  @Override
+  public void run() throws Exception {
+    switch (name) {
+      case "changes":
+        sequences.setChangeIdValue(value);
+        break;
+      case "accounts":
+        sequences.setAccountIdValue(value);
+        break;
+      case "groups":
+        sequences.setGroupIdValue(value);
+        break;
+      default:
+        throw die("Unknown sequence name: " + name);
+    }
+    stdout.print("The value for the " + name + " sequence was set to " + value + ".");
+    stdout.print('\n');
+    stdout.flush();
+  }
+}
diff --git a/java/com/google/gerrit/sshd/commands/SequenceShowCommand.java b/java/com/google/gerrit/sshd/commands/SequenceShowCommand.java
new file mode 100644
index 0000000..490c7ca
--- /dev/null
+++ b/java/com/google/gerrit/sshd/commands/SequenceShowCommand.java
@@ -0,0 +1,54 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.sshd.commands;
+
+import com.google.gerrit.common.data.GlobalCapability;
+import com.google.gerrit.extensions.annotations.RequiresCapability;
+import com.google.gerrit.server.notedb.Sequences;
+import com.google.gerrit.sshd.CommandMetaData;
+import com.google.gerrit.sshd.SshCommand;
+import com.google.inject.Inject;
+import org.kohsuke.args4j.Argument;
+
+/** Display sequence value. */
+@RequiresCapability(GlobalCapability.ADMINISTRATE_SERVER)
+@CommandMetaData(name = "show", description = "Display the sequence value")
+final class SequenceShowCommand extends SshCommand {
+  @Argument(index = 0, metaVar = "NAME", required = true, usage = "sequence name")
+  private String name;
+
+  @Inject Sequences sequences;
+
+  @Override
+  public void run() throws Exception {
+    int current;
+    switch (name) {
+      case "changes":
+        current = sequences.currentChangeId();
+        break;
+      case "accounts":
+        current = sequences.currentAccountId();
+        break;
+      case "groups":
+        current = sequences.currentGroupId();
+        break;
+      default:
+        throw die("Unknown sequence name: " + name);
+    }
+    stdout.print(current);
+    stdout.print('\n');
+    stdout.flush();
+  }
+}
diff --git a/java/com/google/gerrit/sshd/commands/ShowCaches.java b/java/com/google/gerrit/sshd/commands/ShowCaches.java
index db0a481..7e0439f 100644
--- a/java/com/google/gerrit/sshd/commands/ShowCaches.java
+++ b/java/com/google/gerrit/sshd/commands/ShowCaches.java
@@ -197,7 +197,7 @@
     stdout.flush();
   }
 
-  private Collection<CacheInfo> getCaches() throws Exception {
+  private Collection<CacheInfo> getCaches() {
     @SuppressWarnings("unchecked")
     Map<String, CacheInfo> caches =
         (Map<String, CacheInfo>) listCaches.apply(new ConfigResource()).value();
diff --git a/java/com/google/gerrit/testing/BUILD b/java/com/google/gerrit/testing/BUILD
index 5e2fbea..a76275b 100644
--- a/java/com/google/gerrit/testing/BUILD
+++ b/java/com/google/gerrit/testing/BUILD
@@ -13,6 +13,7 @@
         "//lib/mockito",
     ],
     deps = [
+        "//java/com/google/gerrit/acceptance/config",
         "//java/com/google/gerrit/acceptance/testsuite/project",
         "//java/com/google/gerrit/common:annotations",
         "//java/com/google/gerrit/entities",
diff --git a/java/com/google/gerrit/testing/GerritServerTests.java b/java/com/google/gerrit/testing/GerritServerTests.java
index ad985b6..363a07d 100644
--- a/java/com/google/gerrit/testing/GerritServerTests.java
+++ b/java/com/google/gerrit/testing/GerritServerTests.java
@@ -14,6 +14,9 @@
 
 package com.google.gerrit.testing;
 
+import com.google.gerrit.acceptance.config.ConfigAnnotationParser;
+import com.google.gerrit.acceptance.config.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfigs;
 import org.eclipse.jgit.lib.Config;
 import org.junit.Rule;
 import org.junit.rules.TestRule;
@@ -23,16 +26,24 @@
 @RunWith(ConfigSuite.class)
 public class GerritServerTests {
   @ConfigSuite.Parameter public Config config;
-
   @ConfigSuite.Name private String configName;
 
   @Rule
   public TestRule testRunner =
-      (base, description) ->
-          new Statement() {
-            @Override
-            public void evaluate() throws Throwable {
-              base.evaluate();
-            }
-          };
+      (base, description) -> {
+        GerritConfig gerritConfig = description.getAnnotation(GerritConfig.class);
+        if (gerritConfig != null) {
+          config = ConfigAnnotationParser.parse(config, gerritConfig);
+        }
+        GerritConfigs gerritConfigs = description.getAnnotation(GerritConfigs.class);
+        if (gerritConfigs != null) {
+          config = ConfigAnnotationParser.parse(config, gerritConfigs);
+        }
+        return new Statement() {
+          @Override
+          public void evaluate() throws Throwable {
+            base.evaluate();
+          }
+        };
+      };
 }
diff --git a/java/com/google/gerrit/testing/IndexConfig.java b/java/com/google/gerrit/testing/IndexConfig.java
index 21c49dd..fb6c926 100644
--- a/java/com/google/gerrit/testing/IndexConfig.java
+++ b/java/com/google/gerrit/testing/IndexConfig.java
@@ -23,7 +23,9 @@
 
   public static Config createFromExistingConfig(Config cfg) {
     cfg.setInt("index", null, "maxPages", 10);
-    cfg.setBoolean("index", null, "reindexAfterRefUpdate", false);
+    // To avoid this flakiness indexMergeable is switched off for the tests as it incurs background
+    // reindex calls.
+    cfg.setBoolean("index", "change", "indexMergeable", false);
     cfg.setString("trackingid", "query-bug", "footer", "Bug:");
     cfg.setString("trackingid", "query-bug", "match", "QUERY\\d{2,8}");
     cfg.setString("trackingid", "query-bug", "system", "querytests");
diff --git a/java/org/apache/commons/net/BUILD b/java/org/apache/commons/net/BUILD
index c322ecd..d83d8ec 100644
--- a/java/org/apache/commons/net/BUILD
+++ b/java/org/apache/commons/net/BUILD
@@ -6,7 +6,7 @@
     visibility = ["//visibility:public"],
     deps = [
         "//java/com/google/gerrit/util/ssl",
-        "//lib/commons:codec",
+        "//lib:guava",
         "//lib/commons:net",
     ],
 )
diff --git a/java/org/apache/commons/net/smtp/AuthSMTPClient.java b/java/org/apache/commons/net/smtp/AuthSMTPClient.java
index 33dd609..85e4dbf 100644
--- a/java/org/apache/commons/net/smtp/AuthSMTPClient.java
+++ b/java/org/apache/commons/net/smtp/AuthSMTPClient.java
@@ -16,6 +16,7 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.util.ssl.BlindSSLSocketFactory;
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
@@ -33,7 +34,6 @@
 import javax.net.ssl.SSLParameters;
 import javax.net.ssl.SSLSocket;
 import javax.net.ssl.SSLSocketFactory;
-import org.apache.commons.codec.binary.Base64;
 
 public class AuthSMTPClient extends SMTPClient {
   private String authTypes;
@@ -134,7 +134,7 @@
     }
 
     final String enc = getReplyStrings()[0].split(" ", 2)[1];
-    final byte[] nonce = Base64.decodeBase64(enc.getBytes(UTF_8));
+    final byte[] nonce = BaseEncoding.base64().decode(enc);
     final String sec;
     try {
       Mac mac = Mac.getInstance(macName);
@@ -187,6 +187,6 @@
   }
 
   private static String encodeBase64(byte[] data) {
-    return new String(Base64.encodeBase64(data), UTF_8);
+    return BaseEncoding.base64().encode(data);
   }
 }
diff --git a/javatests/com/google/gerrit/acceptance/api/accounts/AccountIT.java b/javatests/com/google/gerrit/acceptance/api/accounts/AccountIT.java
index ba12a12..b375f22 100644
--- a/javatests/com/google/gerrit/acceptance/api/accounts/AccountIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/accounts/AccountIT.java
@@ -59,12 +59,12 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.Sandboxed;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.acceptance.UseClockStep;
 import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.account.TestSshKeys;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
@@ -3010,7 +3010,7 @@
     // Newly created account is not stale.
     AccountInfo accountInfo = gApi.accounts().create(name("foo")).get();
     Account.Id accountId = Account.id(accountInfo._accountId);
-    assertThat(stalenessChecker.isStale(accountId)).isFalse();
+    assertThat(stalenessChecker.check(accountId).isStale()).isFalse();
 
     // Manually updating the user ref makes the index document stale.
     String userRef = RefNames.refsUsers(accountId);
@@ -3078,11 +3078,11 @@
     // has to happen directly on the accounts cache because AccountCacheImpl triggers a reindex for
     // the account.
     accountsCache.invalidate(accountId);
-    assertThat(stalenessChecker.isStale(accountId)).isTrue();
+    assertThat(stalenessChecker.check(accountId).isStale()).isTrue();
 
     // Reindex fixes staleness
     accountIndexer.index(accountId);
-    assertThat(stalenessChecker.isStale(accountId)).isFalse();
+    assertThat(stalenessChecker.check(accountId).isStale()).isFalse();
   }
 
   @Test
diff --git a/javatests/com/google/gerrit/acceptance/api/accounts/AccountManagerIT.java b/javatests/com/google/gerrit/acceptance/api/accounts/AccountManagerIT.java
index 25617d4..a09284e 100644
--- a/javatests/com/google/gerrit/acceptance/api/accounts/AccountManagerIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/accounts/AccountManagerIT.java
@@ -23,7 +23,7 @@
 
 import com.google.common.collect.ImmutableSet;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.server.ServerInitiated;
diff --git a/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java b/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
index 5550d98..3bb0338 100644
--- a/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/accounts/AgreementsIT.java
@@ -21,9 +21,9 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.RawInputUtil;
@@ -239,6 +239,28 @@
   }
 
   @Test
+  public void revertSubmissionWithoutCLA() throws Exception {
+    assume().that(isContributorAgreementsEnabled()).isTrue();
+
+    // Create a change succeeds when agreement is not required
+    setUseContributorAgreements(InheritableBoolean.FALSE);
+    ChangeInfo change = gApi.changes().create(newChangeInput()).get();
+
+    // Approve and submit it
+    requestScopeOperations.setApiUser(admin.id());
+    gApi.changes().id(change.changeId).current().review(ReviewInput.approve());
+    gApi.changes().id(change.changeId).current().submit(new SubmitInput());
+
+    // Revert Submission is not allowed when CLA is required but not signed
+    requestScopeOperations.setApiUser(user.id());
+    setUseContributorAgreements(InheritableBoolean.TRUE);
+    AuthException thrown =
+        assertThrows(
+            AuthException.class, () -> gApi.changes().id(change.changeId).revertSubmission());
+    assertThat(thrown).hasMessageThat().contains("Contributor Agreement");
+  }
+
+  @Test
   public void revertExcludedProjectChangeWithoutCLA() throws Exception {
     // Contributor agreements configured with excludeProjects = ExcludedProject
     // in AbstractDaemonTest.configureContributorAgreement(...)
diff --git a/javatests/com/google/gerrit/acceptance/api/change/AbandonIT.java b/javatests/com/google/gerrit/acceptance/api/change/AbandonIT.java
index 8aebc69..0090ed1 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/AbandonIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/AbandonIT.java
@@ -25,9 +25,9 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.Permission;
diff --git a/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java b/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
index f176663..74f753d 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
@@ -74,13 +74,13 @@
 import com.google.gerrit.acceptance.ChangeIndexedCounter;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.TestProjectInput;
 import com.google.gerrit.acceptance.UseClockStep;
 import com.google.gerrit.acceptance.UseTimezone;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
@@ -249,6 +249,7 @@
     assertThat(c.owner.email).isNull();
     assertThat(c.owner.username).isNull();
     assertThat(c.owner.avatars).isNull();
+    assertThat(c.submissionId).isNull();
   }
 
   @Test
@@ -314,6 +315,15 @@
   }
 
   @Test
+  public void getSubmissionId() throws Exception {
+    PushOneCommit.Result changeResult = createChange();
+    String changeId = changeResult.getChangeId();
+
+    merge(changeResult);
+    assertThat(gApi.changes().id(changeId).get().submissionId).isNotNull();
+  }
+
+  @Test
   public void setWorkInProgressNotAllowedWithoutPermission() throws Exception {
     PushOneCommit.Result rwip = createChange();
     String changeId = rwip.getChangeId();
@@ -2194,7 +2204,7 @@
         gApi.changes().id(r.getChangeId()).reviewer(admin.id().toString()).votes();
 
     assertThat(m).hasSize(1);
-    assertThat(m).containsEntry("Code-Review", Short.valueOf((short) 2));
+    assertThat(m).containsExactly("Code-Review", Short.valueOf((short) 2));
 
     requestScopeOperations.setApiUser(user.id());
     gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).review(ReviewInput.dislike());
@@ -2202,7 +2212,26 @@
     m = gApi.changes().id(r.getChangeId()).reviewer(user.id().toString()).votes();
 
     assertThat(m).hasSize(1);
-    assertThat(m).containsEntry("Code-Review", Short.valueOf((short) -1));
+    assertThat(m).containsExactly("Code-Review", Short.valueOf((short) -1));
+  }
+
+  @Test
+  @GerritConfig(name = "accounts.visibility", value = "NONE")
+  public void listVotesEvenWhenAccountsAreNotVisible() throws Exception {
+    PushOneCommit.Result r = createChange();
+    gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).review(ReviewInput.approve());
+
+    requestScopeOperations.setApiUser(user.id());
+
+    // check finding by address works
+    Map<String, Short> m = gApi.changes().id(r.getChangeId()).reviewer(admin.email()).votes();
+    assertThat(m).hasSize(1);
+    assertThat(m).containsEntry("Code-Review", Short.valueOf((short) 2));
+
+    // check finding by id works
+    m = gApi.changes().id(r.getChangeId()).reviewer(admin.id().toString()).votes();
+    assertThat(m).hasSize(1);
+    assertThat(m).containsEntry("Code-Review", Short.valueOf((short) 2));
   }
 
   @Test
@@ -3380,6 +3409,7 @@
 
     ChangeInfo change = gApi.changes().id(r.getChangeId()).get();
     assertThat(change.status).isEqualTo(ChangeStatus.MERGED);
+    assertThat(change.submissionId).isNotNull();
     assertThat(change.labels.keySet()).containsExactly("Code-Review");
     assertThat(change.permittedLabels.keySet()).containsExactly("Code-Review");
     assertPermitted(change, "Code-Review", 2);
@@ -3540,6 +3570,7 @@
 
     ChangeInfo change = gApi.changes().id(r.getChangeId()).get();
     assertThat(change.status).isEqualTo(ChangeStatus.MERGED);
+    assertThat(change.submissionId).isNotNull();
     assertThat(change.labels.keySet()).containsExactly("Code-Review", "Non-Author-Code-Review");
     assertThat(change.permittedLabels.keySet()).containsExactly("Code-Review");
     assertPermitted(change, "Code-Review", 0, 1, 2);
@@ -3555,11 +3586,34 @@
 
     ChangeInfo change = gApi.changes().id(r.getChangeId()).get();
     assertThat(change.status).isEqualTo(ChangeStatus.MERGED);
+    assertThat(change.submissionId).isNotNull();
     assertThat(change.labels.keySet()).containsExactly("Code-Review");
     assertPermitted(change, "Code-Review", 0, 1, 2);
   }
 
   @Test
+  public void checkSubmissionIdForAutoClosedChange() throws Exception {
+    PushOneCommit.Result first = createChange();
+    PushOneCommit.Result second = createChange();
+
+    PushOneCommit push = pushFactory.create(admin.newIdent(), testRepo);
+
+    PushOneCommit.Result result = push.to("refs/heads/master");
+    result.assertOkStatus();
+
+    ChangeInfo firstChange = gApi.changes().id(first.getChangeId()).get();
+    assertThat(firstChange.status).isEqualTo(ChangeStatus.MERGED);
+    assertThat(firstChange.submissionId).isNotNull();
+
+    ChangeInfo secondChange = gApi.changes().id(second.getChangeId()).get();
+    assertThat(secondChange.status).isEqualTo(ChangeStatus.MERGED);
+    assertThat(secondChange.submissionId).isNotNull();
+
+    assertThat(secondChange.submissionId).isEqualTo(firstChange.submissionId);
+    assertThat(gApi.changes().id(second.getChangeId()).submittedTogether()).hasSize(2);
+  }
+
+  @Test
   public void maxPermittedValueAllowed() throws Exception {
     final int minPermittedValue = -2;
     final int maxPermittedValue = +2;
@@ -4383,6 +4437,20 @@
     }
   }
 
+  @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "true")
+  public void changeQueryReturnsMergeableWhenGerritIndexMergeable() throws Exception {
+    String changeId = createChange().getChangeId();
+    assertThat(gApi.changes().query(changeId).get().get(0).mergeable).isTrue();
+  }
+
+  @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "false")
+  public void changeQueryDoesNotReturnMergeableWhenGerritDoesNotIndexMergeable() throws Exception {
+    String changeId = createChange().getChangeId();
+    assertThat(gApi.changes().query(changeId).get().get(0).mergeable).isNull();
+  }
+
   private PushOneCommit.Result createWorkInProgressChange() throws Exception {
     return pushTo("refs/for/master%wip");
   }
diff --git a/javatests/com/google/gerrit/acceptance/api/change/ChangeIdIT.java b/javatests/com/google/gerrit/acceptance/api/change/ChangeIdIT.java
index b8a4871..a0a88f8 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/ChangeIdIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/ChangeIdIT.java
@@ -18,8 +18,8 @@
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.api.changes.ChangeApi;
diff --git a/javatests/com/google/gerrit/acceptance/api/change/DisablePrivateChangesIT.java b/javatests/com/google/gerrit/acceptance/api/change/DisablePrivateChangesIT.java
index 42d62bd..eee25b8 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/DisablePrivateChangesIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/DisablePrivateChangesIT.java
@@ -18,8 +18,8 @@
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.extensions.common.ChangeInput;
 import com.google.gerrit.extensions.restapi.MethodNotAllowedException;
 import org.junit.Test;
diff --git a/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java b/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java
index 92f914b..b5d673c 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java
@@ -15,21 +15,32 @@
 package com.google.gerrit.acceptance.api.change;
 
 import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.block;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static java.util.stream.Collectors.toList;
+import static javax.servlet.http.HttpServletResponse.SC_OK;
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.server.restapi.change.QueryChanges;
 import com.google.inject.Inject;
 import com.google.inject.Provider;
 import java.util.List;
+import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
+import org.eclipse.jgit.junit.TestRepository;
 import org.junit.Test;
 
 @NoHttpd
 public class QueryChangeIT extends AbstractDaemonTest {
-
+  @Inject private ProjectOperations projectOperations;
   @Inject private Provider<QueryChanges> queryChangesProvider;
 
   @Test
@@ -97,6 +108,93 @@
     assertThat(result2.get(1).get(0)._moreChanges).isTrue();
   }
 
+  @Test
+  @SuppressWarnings("unchecked")
+  @GerritConfig(name = "operator-alias.change.numberaliastest", value = "change")
+  public void aliasQuery() throws Exception {
+    String cId1 = createChange().getChangeId();
+    String cId2 = createChange().getChangeId();
+    int numericId1 = gApi.changes().id(cId1).get()._number;
+    int numericId2 = gApi.changes().id(cId2).get()._number;
+
+    QueryChanges queryChanges = queryChangesProvider.get();
+    queryChanges.addQuery("numberaliastest:12345");
+    queryChanges.addQuery("numberaliastest:" + numericId1);
+    queryChanges.addQuery("numberaliastest:" + numericId2);
+
+    List<List<ChangeInfo>> result =
+        (List<List<ChangeInfo>>) queryChanges.apply(TopLevelResource.INSTANCE).value();
+    assertThat(result).hasSize(3);
+    assertThat(result.get(0)).hasSize(0);
+    assertThat(result.get(1)).hasSize(1);
+    assertThat(result.get(2)).hasSize(1);
+
+    assertThat(result.get(1).get(0)._number).isEqualTo(numericId1);
+    assertThat(result.get(2).get(0)._number).isEqualTo(numericId2);
+  }
+
+  @Test
+  @UseClockStep
+  @SuppressWarnings("unchecked")
+  public void withPagedResults() throws Exception {
+    // Create 4 visible changes.
+    createChange(testRepo).getChange().getId().get();
+    createChange(testRepo).getChange().getId().get();
+    int changeId3 = createChange(testRepo).getChange().getId().get();
+    int changeId4 = createChange(testRepo).getChange().getId().get();
+
+    // Create hidden project.
+    Project.NameKey hiddenProject = projectOperations.newProject().create();
+    projectOperations
+        .project(hiddenProject)
+        .forUpdate()
+        .add(block(Permission.READ).ref("refs/*").group(REGISTERED_USERS))
+        .update();
+    TestRepository<InMemoryRepository> hiddenRepo = cloneProject(hiddenProject, admin);
+
+    // Create 2 hidden changes.
+    createChange(hiddenRepo);
+    createChange(hiddenRepo);
+
+    // Create a change query that matches all changes (visible and hidden changes).
+    // The index returns the changes ordered by last updated timestamp:
+    // hiddenChange2, hiddenChange1, change4, change3, change2, change1
+    QueryChanges queryChanges = queryChangesProvider.get();
+    queryChanges.addQuery("branch:master");
+
+    // Set a limit on the query so that we need to paginate over the results from the index.
+    queryChanges.setLimit(2);
+
+    // Execute the query and verify the results.
+    // Since the limit is set to 2, at most 2 changes are returned to user, but the index query is
+    // executed with limit 3 (+1 so that we can populate the _more_changes field on the last
+    // result).
+    // This means the index query with limit 3 returns these changes:
+    // hiddenChange2, hiddenChange1, change4
+    // The 2 hidden changes are filtered out because they are not visible to the caller.
+    // This means we have only one matching result (change4) but the limit (3) is not exhausted
+    // yet. Hence the next page is loaded from the index (startIndex is 3 to skip the results
+    // that we already processed, limit is again 3). The results for the next page are:
+    // change3, change2, change1
+    // change2 and change1 are dropped because they are over the limit.
+    List<ChangeInfo> result =
+        (List<ChangeInfo>) queryChanges.apply(TopLevelResource.INSTANCE).value();
+    assertThat(result.stream().map(i -> i._number).collect(toList()))
+        .containsExactly(changeId3, changeId4);
+  }
+
+  @Test
+  public void usingOutOfRangeLabelValuesDoesNotCauseError() throws Exception {
+    for (String operator : ImmutableList.of("=", ">", ">=", "<", "<=")) {
+      QueryChanges queryChanges = queryChangesProvider.get();
+      queryChanges.addQuery("label:Code-Review" + operator + "10");
+      queryChanges.addQuery("label:Code-Review" + operator + "-10");
+      queryChanges.addQuery("Code-Review" + operator + "10");
+      queryChanges.addQuery("Code-Review" + operator + "-10");
+      assertThat(queryChanges.apply(TopLevelResource.INSTANCE).statusCode()).isEqualTo(SC_OK);
+    }
+  }
+
   private static void assertNoChangeHasMoreChangesSet(List<ChangeInfo> results) {
     for (ChangeInfo info : results) {
       assertThat(info._moreChanges).isNull();
diff --git a/javatests/com/google/gerrit/acceptance/api/change/RevertIT.java b/javatests/com/google/gerrit/acceptance/api/change/RevertIT.java
index 0607a3c..ec4a3a3 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/RevertIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/RevertIT.java
@@ -23,10 +23,14 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.TestProjectInput;
+import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.Project;
 import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.api.changes.ChangeApi;
 import com.google.gerrit.extensions.api.changes.NotifyHandling;
 import com.google.gerrit.extensions.api.changes.RevertInput;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
@@ -36,6 +40,8 @@
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.ChangeMessageInfo;
 import com.google.gerrit.extensions.common.PureRevertInfo;
+import com.google.gerrit.extensions.common.RevertSubmissionInfo;
+import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
@@ -45,8 +51,10 @@
 import com.google.inject.Inject;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.Repository;
 import org.junit.Test;
@@ -361,17 +369,20 @@
 
   @Test
   public void cantCreateRevertWithoutProjectWritePermission() throws Exception {
-    PushOneCommit.Result r = createChange();
-    gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).review(ReviewInput.approve());
-    gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).submit();
+    PushOneCommit.Result result = createChange();
+    gApi.changes()
+        .id(result.getChangeId())
+        .revision(result.getCommit().name())
+        .review(ReviewInput.approve());
+    gApi.changes().id(result.getChangeId()).revision(result.getCommit().name()).submit();
     projectCache.checkedGet(project).getProject().setState(ProjectState.READ_ONLY);
 
+    String expected = "project state " + ProjectState.READ_ONLY + " does not permit write";
     ResourceConflictException thrown =
         assertThrows(
-            ResourceConflictException.class, () -> gApi.changes().id(r.getChangeId()).revert());
-    assertThat(thrown)
-        .hasMessageThat()
-        .contains("project state " + ProjectState.READ_ONLY + " does not permit write");
+            ResourceConflictException.class,
+            () -> gApi.changes().id(result.getChangeId()).revert());
+    assertThat(thrown).hasMessageThat().contains(expected);
   }
 
   @Test
@@ -412,6 +423,339 @@
     assertThat(thrown).hasMessageThat().contains("Not found: " + r.getChangeId());
   }
 
+  @Test
+  @GerritConfig(name = "change.submitWholeTopic", value = "true")
+  public void cantCreateRevertSubmissionWithoutProjectWritePermission() throws Exception {
+    String secondProject = "secondProject";
+    projectOperations.newProject().name(secondProject).create();
+    TestRepository<InMemoryRepository> secondRepo =
+        cloneProject(Project.nameKey("secondProject"), admin);
+    String topic = "topic";
+    PushOneCommit.Result result1 =
+        createChange(testRepo, "master", "first change", "a.txt", "message", topic);
+    PushOneCommit.Result result2 =
+        createChange(secondRepo, "master", "second change", "b.txt", "message", topic);
+    gApi.changes().id(result1.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result2.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result1.getChangeId()).revision(result1.getCommit().name()).submit();
+
+    // revoke write permissions for the first repository.
+    projectCache.checkedGet(project).getProject().setState(ProjectState.READ_ONLY);
+
+    String expected = "project state " + ProjectState.READ_ONLY + " does not permit write";
+
+    // assert that if first repository has no write permissions, it will fail.
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.changes().id(result1.getChangeId()).revertSubmission());
+    assertThat(thrown).hasMessageThat().contains(expected);
+
+    // assert that if the first repository has no write permissions and a change from another
+    // repository is trying to revert the submission, it will fail.
+    thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.changes().id(result2.getChangeId()).revertSubmission());
+    assertThat(thrown).hasMessageThat().contains(expected);
+  }
+
+  @Test
+  @GerritConfig(name = "change.submitWholeTopic", value = "true")
+  public void cantCreateRevertSubmissionWithoutCreateChangePermission() throws Exception {
+    String secondProject = "secondProject";
+    projectOperations.newProject().name(secondProject).create();
+    TestRepository<InMemoryRepository> secondRepo =
+        cloneProject(Project.nameKey("secondProject"), admin);
+    String topic = "topic";
+    PushOneCommit.Result result1 =
+        createChange(testRepo, "master", "first change", "a.txt", "message", topic);
+    PushOneCommit.Result result2 =
+        createChange(secondRepo, "master", "second change", "b.txt", "message", topic);
+    gApi.changes().id(result1.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result2.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result1.getChangeId()).revision(result1.getCommit().name()).submit();
+
+    // revoke create change permissions for the first repository.
+    projectOperations
+        .project(project)
+        .forUpdate()
+        .add(block(Permission.PUSH).ref("refs/for/*").group(REGISTERED_USERS))
+        .update();
+
+    // assert that if first repository has no write create change, it will fail.
+    PermissionDeniedException thrown =
+        assertThrows(
+            PermissionDeniedException.class,
+            () -> gApi.changes().id(result1.getChangeId()).revertSubmission());
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("not permitted: create change on refs/heads/master");
+
+    // assert that if the first repository has no create change permissions and a change from
+    // another repository is trying to revert the submission, it will fail.
+    thrown =
+        assertThrows(
+            PermissionDeniedException.class,
+            () -> gApi.changes().id(result2.getChangeId()).revertSubmission());
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("not permitted: create change on refs/heads/master");
+  }
+
+  @Test
+  @GerritConfig(name = "change.submitWholeTopic", value = "true")
+  public void cantCreateRevertSubmissionWithoutReadPermission() throws Exception {
+    String secondProject = "secondProject";
+    projectOperations.newProject().name(secondProject).create();
+    TestRepository<InMemoryRepository> secondRepo =
+        cloneProject(Project.nameKey("secondProject"), admin);
+    String topic = "topic";
+    PushOneCommit.Result result1 =
+        createChange(testRepo, "master", "first change", "a.txt", "message", topic);
+    PushOneCommit.Result result2 =
+        createChange(secondRepo, "master", "second change", "b.txt", "message", topic);
+    gApi.changes().id(result1.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result2.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result1.getChangeId()).revision(result1.getCommit().name()).submit();
+
+    // revoke read permissions for the first repository.
+    projectOperations
+        .project(project)
+        .forUpdate()
+        .add(block(Permission.READ).ref("refs/heads/master").group(REGISTERED_USERS))
+        .update();
+
+    // assert that if first repository has no read permissions, it will fail.
+    ResourceNotFoundException resourceNotFoundException =
+        assertThrows(
+            ResourceNotFoundException.class,
+            () -> gApi.changes().id(result1.getChangeId()).revertSubmission());
+    assertThat(resourceNotFoundException)
+        .hasMessageThat()
+        .isEqualTo("Not found: " + result1.getChangeId());
+
+    // assert that if the first repository has no READ permissions and a change from another
+    // repository is trying to revert the submission, it will fail.
+    AuthException authException =
+        assertThrows(
+            AuthException.class, () -> gApi.changes().id(result2.getChangeId()).revertSubmission());
+    assertThat(authException).hasMessageThat().isEqualTo("read not permitted");
+  }
+
+  @Test
+  public void revertSubmissionPreservesReviewersAndCcs() throws Exception {
+    PushOneCommit.Result r = createChange("first change", "a.txt", "message");
+
+    ReviewInput in = ReviewInput.approve();
+    in.reviewer(user.email());
+    in.reviewer(accountCreator.user2().email(), ReviewerState.CC, true);
+    // Add user as reviewer that will create the revert
+    in.reviewer(accountCreator.admin2().email());
+
+    gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).review(in);
+    gApi.changes().id(r.getChangeId()).revision(r.getCommit().name()).submit();
+
+    // expect both the original reviewers and CCs to be preserved
+    // original owner should be added as reviewer, user requesting the revert (new owner) removed
+    requestScopeOperations.setApiUser(accountCreator.admin2().id());
+    Map<ReviewerState, Collection<AccountInfo>> result =
+        getChangeApis(gApi.changes().id(r.getChangeId()).revertSubmission()).get(0).get().reviewers;
+    assertThat(result).containsKey(ReviewerState.REVIEWER);
+
+    List<Integer> reviewers =
+        result.get(ReviewerState.REVIEWER).stream().map(a -> a._accountId).collect(toList());
+    assertThat(result).containsKey(ReviewerState.CC);
+    List<Integer> ccs =
+        result.get(ReviewerState.CC).stream().map(a -> a._accountId).collect(toList());
+    assertThat(ccs).containsExactly(accountCreator.user2().id().get());
+    assertThat(reviewers).containsExactly(user.id().get(), admin.id().get());
+  }
+
+  @Test
+  public void revertSubmissionNotifications() throws Exception {
+    PushOneCommit.Result firstResult = createChange("first change", "a.txt", "message");
+    approve(firstResult.getChangeId());
+    gApi.changes().id(firstResult.getChangeId()).addReviewer(user.email());
+    PushOneCommit.Result secondResult = createChange("second change", "b.txt", "other");
+    approve(secondResult.getChangeId());
+    gApi.changes().id(secondResult.getChangeId()).addReviewer(user.email());
+
+    gApi.changes()
+        .id(secondResult.getChangeId())
+        .revision(secondResult.getCommit().name())
+        .submit();
+
+    sender.clear();
+    RevertInput revertInput = new RevertInput();
+    revertInput.notify = NotifyHandling.ALL;
+
+    RevertSubmissionInfo revertChanges =
+        gApi.changes().id(secondResult.getChangeId()).revertSubmission(revertInput);
+
+    List<Message> messages = sender.getMessages();
+
+    assertThat(messages).hasSize(4);
+    assertThat(sender.getMessages(revertChanges.revertChanges.get(0).changeId, "newchange"))
+        .hasSize(1);
+    assertThat(sender.getMessages(firstResult.getChangeId(), "revert")).hasSize(1);
+    assertThat(sender.getMessages(revertChanges.revertChanges.get(1).changeId, "newchange"))
+        .hasSize(1);
+    assertThat(sender.getMessages(secondResult.getChangeId(), "revert")).hasSize(1);
+  }
+
+  @Test
+  public void suppressRevertSubmissionNotifications() throws Exception {
+    PushOneCommit.Result firstResult = createChange("first change", "a.txt", "message");
+    approve(firstResult.getChangeId());
+    gApi.changes().id(firstResult.getChangeId()).addReviewer(user.email());
+    PushOneCommit.Result secondResult = createChange("second change", "b.txt", "other");
+    approve(secondResult.getChangeId());
+    gApi.changes().id(secondResult.getChangeId()).addReviewer(user.email());
+
+    gApi.changes()
+        .id(secondResult.getChangeId())
+        .revision(secondResult.getCommit().name())
+        .submit();
+
+    RevertInput revertInput = new RevertInput();
+    revertInput.notify = NotifyHandling.NONE;
+
+    sender.clear();
+    gApi.changes().id(secondResult.getChangeId()).revertSubmission(revertInput);
+    assertThat(sender.getMessages()).isEmpty();
+  }
+
+  @Test
+  public void revertSubmissionOfSingleChange() throws Exception {
+    PushOneCommit.Result result = createChange("Change", "a.txt", "message");
+    approve(result.getChangeId());
+    gApi.changes().id(result.getChangeId()).current().submit();
+    List<ChangeApi> revertChanges =
+        getChangeApis(gApi.changes().id(result.getChangeId()).revertSubmission());
+
+    String sha1Commit = result.getCommit().getName();
+
+    assertThat(revertChanges.get(0).current().commit(false).parents.get(0).commit)
+        .isEqualTo(sha1Commit);
+
+    assertThat(revertChanges.get(0).current().files().get("a.txt").linesDeleted).isEqualTo(1);
+
+    assertThat(revertChanges.get(0).get().revertOf)
+        .isEqualTo(result.getChange().change().getChangeId());
+    assertThat(revertChanges.get(0).get().topic)
+        .startsWith("revert-" + result.getChange().change().getSubmissionId() + "-");
+  }
+
+  @Test
+  public void revertSubmissionWithSetTopic() throws Exception {
+    PushOneCommit.Result result = createChange();
+    gApi.changes().id(result.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result.getChangeId()).topic("topic");
+    gApi.changes().id(result.getChangeId()).revision(result.getCommit().name()).submit();
+    RevertInput revertInput = new RevertInput();
+    revertInput.topic = "reverted-not-default";
+    assertThat(
+            gApi.changes()
+                .id(result.getChangeId())
+                .revertSubmission(revertInput)
+                .revertChanges
+                .get(0)
+                .topic)
+        .isEqualTo(revertInput.topic);
+  }
+
+  @Test
+  public void revertSubmissionWithSetMessage() throws Exception {
+    PushOneCommit.Result result = createChange();
+    gApi.changes().id(result.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(result.getChangeId()).revision(result.getCommit().name()).submit();
+    RevertInput revertInput = new RevertInput();
+    revertInput.message = "Message from input";
+    assertThat(
+            gApi.changes()
+                .id(result.getChangeId())
+                .revertSubmission(revertInput)
+                .revertChanges
+                .get(0)
+                .subject)
+        .isEqualTo(revertInput.message);
+  }
+
+  @Test
+  @GerritConfig(name = "change.submitWholeTopic", value = "true")
+  @UseClockStep
+  public void revertSubmissionDifferentRepositoriesWithDependantChange() throws Exception {
+    projectOperations.newProject().name("secondProject").create();
+    TestRepository<InMemoryRepository> secondRepo =
+        cloneProject(Project.nameKey("secondProject"), admin);
+    List<PushOneCommit.Result> resultCommits = new ArrayList<>();
+    String topic = "topic";
+    resultCommits.add(createChange(testRepo, "master", "first change", "a.txt", "message", topic));
+    resultCommits.add(
+        createChange(secondRepo, "master", "first change", "a.txt", "message", topic));
+    resultCommits.add(
+        createChange(secondRepo, "master", "second change", "b.txt", "Other message", topic));
+    for (PushOneCommit.Result result : resultCommits) {
+      approve(result.getChangeId());
+    }
+    // submit all changes
+    gApi.changes().id(resultCommits.get(1).getChangeId()).current().submit();
+    List<ChangeApi> revertChanges =
+        getChangeApis(gApi.changes().id(resultCommits.get(1).getChangeId()).revertSubmission());
+
+    // The reverts are by update time, so the reversal ensures that
+    // revertChanges[i] is the revert of resultCommits[i]
+    Collections.reverse(revertChanges);
+
+    assertThat(revertChanges.get(0).current().files().get("a.txt").linesDeleted).isEqualTo(1);
+    assertThat(revertChanges.get(1).current().files().get("a.txt").linesDeleted).isEqualTo(1);
+    assertThat(revertChanges.get(2).current().files().get("b.txt").linesDeleted).isEqualTo(1);
+    // has size 3 because of the same topic, and submitWholeTopic is true.
+    assertThat(gApi.changes().id(revertChanges.get(0).get()._number).submittedTogether())
+        .hasSize(3);
+
+    // expected messages on source change:
+    // 1. Uploaded patch set 1.
+    // 2. Patch Set 1: Code-Review+2
+    // 3. Change has been successfully merged by Administrator
+    // 4. Created a revert of this change as %s
+
+    for (int i = 0; i < resultCommits.size(); i++) {
+      assertThat(revertChanges.get(i).current().commit(false).parents.get(0).commit)
+          .isEqualTo(resultCommits.get(i).getCommit().getName());
+      assertThat(revertChanges.get(i).get().revertOf)
+          .isEqualTo(resultCommits.get(i).getChange().change().getChangeId());
+      List<ChangeMessageInfo> sourceMessages =
+          new ArrayList<>(gApi.changes().id(resultCommits.get(i).getChangeId()).get().messages);
+      assertThat(sourceMessages).hasSize(4);
+      String expectedMessage =
+          String.format(
+              "Created a revert of this change as %s", revertChanges.get(i).get().changeId);
+      assertThat(sourceMessages.get(3).message).isEqualTo(expectedMessage);
+      // Expected message on the created change: "Uploaded patch set 1."
+      List<ChangeMessageInfo> messages =
+          revertChanges.get(i).get().messages.stream().collect(toList());
+      assertThat(messages).hasSize(1);
+      assertThat(messages.get(0).message).isEqualTo("Uploaded patch set 1.");
+      assertThat(revertChanges.get(i).get().revertOf)
+          .isEqualTo(gApi.changes().id(resultCommits.get(i).getChangeId()).get()._number);
+      assertThat(revertChanges.get(i).get().topic)
+          .startsWith("revert-" + resultCommits.get(0).getChange().change().getSubmissionId());
+    }
+  }
+
+  @Test
+  public void cantRevertSubmissionWithAnOpenChange() throws Exception {
+    PushOneCommit.Result result = createChange("first change", "a.txt", "message");
+    approve(result.getChangeId());
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.changes().id(result.getChangeId()).revertSubmission());
+    assertThat(thrown).hasMessageThat().isEqualTo("change is new.");
+  }
+
   @Override
   protected PushOneCommit.Result createChange() throws Exception {
     return createChange("refs/for/master");
@@ -451,4 +795,13 @@
           .create();
     }
   }
+
+  private List<ChangeApi> getChangeApis(RevertSubmissionInfo revertSubmissionInfo)
+      throws Exception {
+    List<ChangeApi> results = new ArrayList<>();
+    for (ChangeInfo changeInfo : revertSubmissionInfo.revertChanges) {
+      results.add(gApi.changes().id(changeInfo._number));
+    }
+    return results;
+  }
 }
diff --git a/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java b/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
index 07fb577..988580e 100644
--- a/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/group/GroupsIT.java
@@ -40,7 +40,6 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.ProjectResetter;
@@ -48,6 +47,7 @@
 import com.google.gerrit.acceptance.Sandboxed;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
@@ -187,6 +187,24 @@
   }
 
   @Test
+  public void removeMember_nullInMemberInputDoesNotCauseFailure() throws Exception {
+    AccountGroup.UUID group =
+        groupOperations.newGroup().addMember(admin.id()).addMember(user.id()).create();
+    gApi.groups().id(group.get()).removeMembers(user.id().toString(), null);
+    ImmutableSet<Account.Id> members = groupOperations.group(group).get().members();
+    assertThat(members).containsExactly(admin.id());
+  }
+
+  @Test
+  public void removeMember_emptyStringInMemberInputDoesNotCauseFailure() throws Exception {
+    AccountGroup.UUID group =
+        groupOperations.newGroup().addMember(admin.id()).addMember(user.id()).create();
+    gApi.groups().id(group.get()).removeMembers(user.id().toString(), "");
+    ImmutableSet<Account.Id> members = groupOperations.group(group).get().members();
+    assertThat(members).containsExactly(admin.id());
+  }
+
+  @Test
   public void cachedGroupsForMemberAreUpdatedOnMemberAdditionAndRemoval() throws Exception {
     String username = name("user");
     Account.Id accountId = accountOperations.newAccount().username(username).create();
@@ -1265,7 +1283,7 @@
     // Newly created group is not stale
     GroupInfo groupInfo = gApi.groups().create(name("foo")).get();
     AccountGroup.UUID groupUuid = AccountGroup.uuid(groupInfo.id);
-    assertThat(stalenessChecker.isStale(groupUuid)).isFalse();
+    assertThat(stalenessChecker.check(groupUuid).isStale()).isFalse();
 
     // Manual update makes index document stale
     String groupRef = RefNames.refsGroups(groupUuid);
@@ -1406,11 +1424,11 @@
   private void assertStaleGroupAndReindex(AccountGroup.UUID groupUuid) throws IOException {
     // Evict group from cache to be sure that we use the index state for staleness checks.
     groupCache.evict(groupUuid);
-    assertThat(stalenessChecker.isStale(groupUuid)).isTrue();
+    assertThat(stalenessChecker.check(groupUuid).isStale()).isTrue();
 
     // Reindex fixes staleness
     groupIndexer.index(groupUuid);
-    assertThat(stalenessChecker.isStale(groupUuid)).isFalse();
+    assertThat(stalenessChecker.check(groupUuid).isStale()).isFalse();
   }
 
   private void pushToGroupBranchForReviewAndSubmit(
diff --git a/javatests/com/google/gerrit/acceptance/api/plugin/PluginIT.java b/javatests/com/google/gerrit/acceptance/api/plugin/PluginIT.java
index a120eac..ff873dd 100644
--- a/javatests/com/google/gerrit/acceptance/api/plugin/PluginIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/plugin/PluginIT.java
@@ -21,8 +21,8 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.RawInputUtil;
 import com.google.gerrit.extensions.api.plugins.InstallPluginInput;
diff --git a/javatests/com/google/gerrit/acceptance/api/plugin/PluginLoaderIT.java b/javatests/com/google/gerrit/acceptance/api/plugin/PluginLoaderIT.java
index 7eb3680..744cc2a 100644
--- a/javatests/com/google/gerrit/acceptance/api/plugin/PluginLoaderIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/plugin/PluginLoaderIT.java
@@ -15,8 +15,8 @@
 package com.google.gerrit.acceptance.api.plugin;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.server.plugins.MissingMandatoryPluginsException;
 import org.junit.Test;
 import org.junit.runner.Description;
diff --git a/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java b/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
index eebcc5b..2801b36 100644
--- a/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/project/ProjectIT.java
@@ -35,10 +35,10 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.Nullable;
@@ -49,6 +49,7 @@
 import com.google.gerrit.extensions.annotations.Exports;
 import com.google.gerrit.extensions.api.projects.BranchInput;
 import com.google.gerrit.extensions.api.projects.CommentLinkInfo;
+import com.google.gerrit.extensions.api.projects.CommentLinkInput;
 import com.google.gerrit.extensions.api.projects.ConfigInfo;
 import com.google.gerrit.extensions.api.projects.ConfigInput;
 import com.google.gerrit.extensions.api.projects.ConfigValue;
@@ -68,11 +69,16 @@
 import com.google.gerrit.server.group.SystemGroupBackend;
 import com.google.gerrit.server.index.IndexExecutor;
 import com.google.gerrit.server.project.CommentLinkInfoImpl;
+import com.google.gerrit.server.project.ProjectConfig;
 import com.google.inject.AbstractModule;
 import com.google.inject.Inject;
 import com.google.inject.Module;
 import java.util.HashMap;
 import java.util.Map;
+import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
+import org.eclipse.jgit.junit.TestRepository;
+import org.eclipse.jgit.lib.Config;
+import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.transport.PushResult;
 import org.eclipse.jgit.transport.RemoteRefUpdate.Status;
@@ -717,6 +723,191 @@
     assertCommentLinks(getConfig(), expected);
   }
 
+  @Test
+  public void projectConfigUsesLocallySetCommentlinks() throws Exception {
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK);
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(info, expected);
+    assertCommentLinks(getConfig(), expected);
+  }
+
+  @Test
+  @GerritConfig(name = "commentlink.bugzilla.match", value = BUGZILLA_MATCH)
+  @GerritConfig(name = "commentlink.bugzilla.link", value = BUGZILLA_LINK)
+  public void projectConfigUsesCommentLinksFromGlobalAndLocal() throws Exception {
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    assertCommentLinks(getConfig(), expected);
+
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+
+    assertCommentLinks(info, expected);
+    assertCommentLinks(getConfig(), expected);
+  }
+
+  @Test
+  @GerritConfig(name = "commentlink.bugzilla.match", value = BUGZILLA_MATCH)
+  @GerritConfig(name = "commentlink.bugzilla.link", value = BUGZILLA_LINK)
+  public void localCommentLinkOverridesGlobalConfig() throws Exception {
+    String otherLink = "https://other.example.com";
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, otherLink);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, otherLink));
+
+    ConfigInfo info = setConfig(project, input);
+    assertCommentLinks(info, expected);
+    assertCommentLinks(getConfig(), expected);
+  }
+
+  @Test
+  public void localCommentLinksAreInheritedFromParent() throws Exception {
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK);
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(info, expected);
+
+    Project.NameKey child = projectOperations.newProject().parent(project).create();
+    assertCommentLinks(getConfig(child), expected);
+  }
+
+  @Test
+  public void localCommentLinkOverridesParentCommentLink() throws Exception {
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK);
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(info, expected);
+
+    Project.NameKey child = projectOperations.newProject().parent(project).create();
+
+    String otherLink = "https://other.example.com";
+    input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, otherLink);
+    info = setConfig(child, input);
+
+    expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, otherLink));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+
+    assertCommentLinks(getConfig(child), expected);
+  }
+
+  @Test
+  public void updateExistingCommentLink() throws Exception {
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK);
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(info, expected);
+
+    String otherLink = "https://other.example.com";
+    input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, otherLink);
+    info = setConfig(project, input);
+
+    expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, otherLink));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(getConfig(project), expected);
+  }
+
+  @Test
+  public void removeCommentLink() throws Exception {
+    ConfigInput input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK);
+    addCommentLink(input, JIRA, JIRA_MATCH, JIRA_LINK);
+    ConfigInfo info = setConfig(project, input);
+
+    Map<String, CommentLinkInfo> expected = new HashMap<>();
+    expected.put(BUGZILLA, commentLinkInfo(BUGZILLA, BUGZILLA_MATCH, BUGZILLA_LINK));
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(info, expected);
+
+    input = new ConfigInput();
+    addCommentLink(input, BUGZILLA, null);
+    info = setConfig(project, input);
+
+    expected = new HashMap<>();
+    expected.put(JIRA, commentLinkInfo(JIRA, JIRA_MATCH, JIRA_LINK));
+    assertCommentLinks(getConfig(project), expected);
+  }
+
+  @Test
+  public void cannotPushLabelDefinitionWithDuplicateValues() throws Exception {
+    Config cfg = new Config();
+    cfg.fromText(projectOperations.project(allProjects).getConfig().toText());
+    cfg.setStringList(
+        "label",
+        "Code-Review",
+        "value",
+        ImmutableList.of("+1 LGTM", "1 LGTM", "0 No Value", "-1 Looks Bad"));
+
+    TestRepository<InMemoryRepository> repo = cloneProject(allProjects);
+    GitUtil.fetch(repo, RefNames.REFS_CONFIG + ":" + RefNames.REFS_CONFIG);
+    repo.reset(RefNames.REFS_CONFIG);
+    PushOneCommit.Result r =
+        pushFactory
+            .create(admin.newIdent(), repo, "Subject", "project.config", cfg.toText())
+            .to(RefNames.REFS_CONFIG);
+    r.assertErrorStatus("invalid project configuration");
+    r.assertMessage("project.config: duplicate value \"1 lgtm\" for label \"code-review\"");
+  }
+
+  @Test
+  public void getProjectThatHasLabelDefinitionWithDuplicateValues() throws Exception {
+    // Update the definition of the Code-Review label so that it has the value "+1 LGTM" twice.
+    // This update bypasses all validation checks so that the duplicate label value doesn't get
+    // rejected.
+    Config cfg = new Config();
+    cfg.fromText(projectOperations.project(allProjects).getConfig().toText());
+    cfg.setStringList(
+        "label",
+        "Code-Review",
+        "value",
+        ImmutableList.of("+1 LGTM", "1 LGTM", "0 No Value", "-1 Looks Bad"));
+
+    try (TestRepository<Repository> repo =
+        new TestRepository<>(repoManager.openRepository(allProjects))) {
+      repo.update(
+          RefNames.REFS_CONFIG,
+          repo.commit()
+              .message("Set label with duplicate value")
+              .parent(getHead(repo.getRepository(), RefNames.REFS_CONFIG))
+              .add(ProjectConfig.PROJECT_CONFIG, cfg.toText()));
+    }
+
+    // Verify that project info can be retrieved and that the label value "+1 LGTM" appears only
+    // once.
+    ProjectInfo projectInfo = gApi.projects().name(allProjects.get()).get();
+    assertThat(projectInfo.labels.keySet()).containsExactly("Code-Review");
+    assertThat(projectInfo.labels.get("Code-Review").values)
+        .containsExactly("+1", "LGTM", " 0", "No Value", "-1", "Looks Bad");
+  }
+
   private CommentLinkInfo commentLinkInfo(String name, String match, String link) {
     return new CommentLinkInfoImpl(name, match, link, null /*html*/, null /*enabled*/);
   }
@@ -725,6 +916,21 @@
     assertThat(actual.commentlinks).containsExactlyEntriesIn(expected);
   }
 
+  private void addCommentLink(ConfigInput configInput, String name, String match, String link) {
+    CommentLinkInput commentLinkInput = new CommentLinkInput();
+    commentLinkInput.match = match;
+    commentLinkInput.link = link;
+    addCommentLink(configInput, name, commentLinkInput);
+  }
+
+  private void addCommentLink(
+      ConfigInput configInput, String name, CommentLinkInput commentLinkInput) {
+    if (configInput.commentLinks == null) {
+      configInput.commentLinks = new HashMap<>();
+    }
+    configInput.commentLinks.put(name, commentLinkInput);
+  }
+
   private ConfigInfo setConfig(Project.NameKey name, ConfigInput input) throws Exception {
     return gApi.projects().name(name.get()).config(input);
   }
diff --git a/javatests/com/google/gerrit/acceptance/api/project/ProjectIndexerIT.java b/javatests/com/google/gerrit/acceptance/api/project/ProjectIndexerIT.java
index 019df0e..023f43e 100644
--- a/javatests/com/google/gerrit/acceptance/api/project/ProjectIndexerIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/project/ProjectIndexerIT.java
@@ -83,19 +83,19 @@
 
   @Test
   public void stalenessChecker_currentProject_notStale() throws Exception {
-    assertThat(stalenessChecker.isStale(project)).isFalse();
+    assertThat(stalenessChecker.check(project).isStale()).isFalse();
   }
 
   @Test
   public void stalenessChecker_currentProjectUpdates_isStale() throws Exception {
     updateProjectConfigWithoutIndexUpdate(project);
-    assertThat(stalenessChecker.isStale(project)).isTrue();
+    assertThat(stalenessChecker.check(project).isStale()).isTrue();
   }
 
   @Test
   public void stalenessChecker_parentProjectUpdates_isStale() throws Exception {
     updateProjectConfigWithoutIndexUpdate(allProjects);
-    assertThat(stalenessChecker.isStale(project)).isTrue();
+    assertThat(stalenessChecker.check(project).isStale()).isTrue();
   }
 
   @Test
@@ -106,10 +106,10 @@
       u.getConfig().getProject().setParentName(p1);
       u.save();
     }
-    assertThat(stalenessChecker.isStale(project)).isFalse();
+    assertThat(stalenessChecker.check(project).isStale()).isFalse();
 
     updateProjectConfigWithoutIndexUpdate(p1, c -> c.getProject().setParentName(p2));
-    assertThat(stalenessChecker.isStale(project)).isTrue();
+    assertThat(stalenessChecker.check(project).isStale()).isTrue();
   }
 
   private void updateProjectConfigWithoutIndexUpdate(Project.NameKey project) throws Exception {
diff --git a/javatests/com/google/gerrit/acceptance/api/project/SetParentIT.java b/javatests/com/google/gerrit/acceptance/api/project/SetParentIT.java
index cf7aab4..1539334 100644
--- a/javatests/com/google/gerrit/acceptance/api/project/SetParentIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/project/SetParentIT.java
@@ -19,8 +19,8 @@
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.Permission;
diff --git a/javatests/com/google/gerrit/acceptance/api/revision/RevisionIT.java b/javatests/com/google/gerrit/acceptance/api/revision/RevisionIT.java
index 32941ff..61d0fd5 100644
--- a/javatests/com/google/gerrit/acceptance/api/revision/RevisionIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/revision/RevisionIT.java
@@ -46,6 +46,7 @@
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.acceptance.TestProjectInput;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.Permission;
@@ -1062,6 +1063,7 @@
   }
 
   @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "true")
   public void mergeable() throws Exception {
     ObjectId initial = repo().exactRef(HEAD).getLeaf().getObjectId();
 
@@ -1328,6 +1330,23 @@
   }
 
   @Test
+  public void cannotGetContentOfDirectory() throws Exception {
+    Map<String, String> files = ImmutableMap.of("dir/file1.txt", "content 1");
+    PushOneCommit.Result result =
+        pushFactory.create(admin.newIdent(), testRepo, SUBJECT, files).to("refs/for/master");
+    result.assertOkStatus();
+
+    assertThrows(
+        BadRequestException.class,
+        () ->
+            gApi.changes()
+                .id(result.getChangeId())
+                .revision(result.getCommit().name())
+                .file("dir")
+                .content());
+  }
+
+  @Test
   public void contentType() throws Exception {
     PushOneCommit.Result r = createChange();
 
diff --git a/javatests/com/google/gerrit/acceptance/api/revision/RobotCommentsIT.java b/javatests/com/google/gerrit/acceptance/api/revision/RobotCommentsIT.java
index 62a7037..e3b7456 100644
--- a/javatests/com/google/gerrit/acceptance/api/revision/RobotCommentsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/revision/RobotCommentsIT.java
@@ -25,8 +25,8 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
 import com.google.gerrit.extensions.api.changes.ReviewInput.RobotCommentInput;
 import com.google.gerrit.extensions.client.Comment;
diff --git a/javatests/com/google/gerrit/acceptance/config/BUILD b/javatests/com/google/gerrit/acceptance/config/BUILD
new file mode 100644
index 0000000..350f2e6
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/config/BUILD
@@ -0,0 +1,7 @@
+load("//javatests/com/google/gerrit/acceptance:tests.bzl", "acceptance_tests")
+
+acceptance_tests(
+    srcs = glob(["*.java"]),
+    group = "config",
+    labels = ["config"],
+)
diff --git a/javatests/com/google/gerrit/acceptance/annotation/UseGerritConfigAnnotationTest.java b/javatests/com/google/gerrit/acceptance/config/UseGerritConfigAnnotationTest.java
similarity index 96%
rename from javatests/com/google/gerrit/acceptance/annotation/UseGerritConfigAnnotationTest.java
rename to javatests/com/google/gerrit/acceptance/config/UseGerritConfigAnnotationTest.java
index d5ac2f7..f72aa74 100644
--- a/javatests/com/google/gerrit/acceptance/annotation/UseGerritConfigAnnotationTest.java
+++ b/javatests/com/google/gerrit/acceptance/config/UseGerritConfigAnnotationTest.java
@@ -12,12 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance.annotation;
+package com.google.gerrit.acceptance.config;
 
 import static com.google.common.truth.Truth.assertThat;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import org.junit.Test;
 
 public class UseGerritConfigAnnotationTest extends AbstractDaemonTest {
diff --git a/javatests/com/google/gerrit/acceptance/annotation/UseGlobalPluginConfigAnnotationTest.java b/javatests/com/google/gerrit/acceptance/config/UseGlobalPluginConfigAnnotationTest.java
similarity index 96%
rename from javatests/com/google/gerrit/acceptance/annotation/UseGlobalPluginConfigAnnotationTest.java
rename to javatests/com/google/gerrit/acceptance/config/UseGlobalPluginConfigAnnotationTest.java
index 44d9e46..cfad6f2 100644
--- a/javatests/com/google/gerrit/acceptance/annotation/UseGlobalPluginConfigAnnotationTest.java
+++ b/javatests/com/google/gerrit/acceptance/config/UseGlobalPluginConfigAnnotationTest.java
@@ -12,12 +12,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.gerrit.acceptance.annotation;
+package com.google.gerrit.acceptance.config;
 
 import static com.google.common.truth.Truth.assertThat;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GlobalPluginConfig;
 import com.google.gerrit.acceptance.UseLocalDisk;
 import org.eclipse.jgit.lib.Config;
 import org.junit.Test;
diff --git a/javatests/com/google/gerrit/acceptance/filter/BUILD b/javatests/com/google/gerrit/acceptance/filter/BUILD
new file mode 100644
index 0000000..22aead3
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/filter/BUILD
@@ -0,0 +1,22 @@
+load("//javatests/com/google/gerrit/acceptance:tests.bzl", "acceptance_tests")
+
+acceptance_tests(
+    srcs = glob([
+        "*IT.java",
+    ]),
+    group = "filter",
+    labels = ["filter"],
+    deps = [
+        ":util",
+    ],
+)
+
+java_library(
+    name = "util",
+    testonly = True,
+    srcs = [
+        "FakeMustInitParamsFilter.java",
+        "FakeNoInitParamsFilter.java",
+    ],
+    deps = ["//java/com/google/gerrit/acceptance:lib"],
+)
diff --git a/javatests/com/google/gerrit/acceptance/filter/FakeMustInitParamsFilter.java b/javatests/com/google/gerrit/acceptance/filter/FakeMustInitParamsFilter.java
new file mode 100644
index 0000000..89d268e
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/filter/FakeMustInitParamsFilter.java
@@ -0,0 +1,56 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.filter;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+public class FakeMustInitParamsFilter implements Filter {
+
+  // `PARAM_X` and `PARAM_Y` are init param keys
+  private static final String INIT_PARAM_1 = "PARAM-1";
+  private static final String INIT_PARAM_2 = "PARAM-2";
+  // the map is used for testing
+  private static final Map<String, String> initParams = new HashMap<>();
+
+  @Override
+  public void init(FilterConfig filterConfig) throws ServletException {
+    initParams.put(INIT_PARAM_1, filterConfig.getInitParameter(INIT_PARAM_1));
+    initParams.put(INIT_PARAM_2, filterConfig.getInitParameter(INIT_PARAM_2));
+  }
+
+  @Override
+  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
+      throws IOException, ServletException {
+    chain.doFilter(request, response);
+  }
+
+  @Override
+  public void destroy() {
+    // do nothing.
+  }
+
+  // the function is used for testing
+  Map<String, String> getInitParams() {
+    return initParams;
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/filter/FakeNoInitParamsFilter.java b/javatests/com/google/gerrit/acceptance/filter/FakeNoInitParamsFilter.java
new file mode 100644
index 0000000..6fd6366
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/filter/FakeNoInitParamsFilter.java
@@ -0,0 +1,42 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.filter;
+
+import java.io.IOException;
+import javax.servlet.Filter;
+import javax.servlet.FilterChain;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+
+public class FakeNoInitParamsFilter implements Filter {
+  @Override
+  public void init(FilterConfig filterConfig) throws ServletException {
+    // no init params in this filter.
+    // do nothing.
+  }
+
+  @Override
+  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
+      throws IOException, ServletException {
+    chain.doFilter(request, response);
+  }
+
+  @Override
+  public void destroy() {
+    // do nothing.
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/filter/FilterClassIT.java b/javatests/com/google/gerrit/acceptance/filter/FilterClassIT.java
new file mode 100644
index 0000000..a23c5ce
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/filter/FilterClassIT.java
@@ -0,0 +1,57 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.filter;
+
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.testing.ConfigSuite;
+import org.eclipse.jgit.errors.ConfigInvalidException;
+import org.eclipse.jgit.lib.Config;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class FilterClassIT extends AbstractDaemonTest {
+  @ConfigSuite.Default
+  public static Config enableFilter() throws ConfigInvalidException {
+    Config cfg = new Config();
+    cfg.fromText(
+        ""
+            + "[httpd]\n"
+            + "    filterClass = com.google.gerrit.acceptance.filter.FakeNoInitParamsFilter\n"
+            + "    filterClass = com.google.gerrit.acceptance.filter.FakeMustInitParamsFilter\n"
+            + "[filterClass \"com.google.gerrit.acceptance.filter.FakeMustInitParamsFilter\"]\n"
+            + "    PARAM-1 = hello\n"
+            + "    PARAM-2 = world\n");
+    return cfg;
+  }
+
+  @Test
+  public void filterLoad() {
+    FakeNoInitParamsFilter fakeNoInitParamsFilter =
+        server.getTestInjector().getBinding(FakeNoInitParamsFilter.class).getProvider().get();
+    Assert.assertNotNull(fakeNoInitParamsFilter);
+    FakeMustInitParamsFilter fakeMustInitParamsFilter =
+        server.getTestInjector().getBinding(FakeMustInitParamsFilter.class).getProvider().get();
+    Assert.assertNotNull(fakeMustInitParamsFilter);
+  }
+
+  @Test
+  public void filterInitParams() {
+    FakeMustInitParamsFilter fakeMustInitParamsFilter =
+        server.getTestInjector().getBinding(FakeMustInitParamsFilter.class).getProvider().get();
+    Assert.assertEquals(2, fakeMustInitParamsFilter.getInitParams().size());
+    Assert.assertEquals("hello", fakeMustInitParamsFilter.getInitParams().get("PARAM-1"));
+    Assert.assertEquals("world", fakeMustInitParamsFilter.getInitParams().get("PARAM-2"));
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java b/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
index cab12b3..60cf4f1 100644
--- a/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
+++ b/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
@@ -52,13 +52,13 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.SkipProjectClone;
 import com.google.gerrit.acceptance.TestAccount;
 import com.google.gerrit.acceptance.TestProjectInput;
 import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.GlobalCapability;
diff --git a/javatests/com/google/gerrit/acceptance/git/RefAdvertisementIT.java b/javatests/com/google/gerrit/acceptance/git/RefAdvertisementIT.java
index 0ac40a0..d1d197b 100644
--- a/javatests/com/google/gerrit/acceptance/git/RefAdvertisementIT.java
+++ b/javatests/com/google/gerrit/acceptance/git/RefAdvertisementIT.java
@@ -29,10 +29,10 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.TestAccount;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.Nullable;
@@ -1446,7 +1446,7 @@
   private TestRefAdvertiser.Result getReceivePackRefs() throws Exception {
     try (Repository repo = repoManager.openRepository(project)) {
       AdvertiseRefsHook adv =
-          ReceiveCommitsAdvertiseRefsHookChain.createForTest(queryProvider, project);
+          ReceiveCommitsAdvertiseRefsHookChain.createForTest(queryProvider, project, admin.id());
       ReceivePack rp = new ReceivePack(repo);
       rp.setAdvertiseRefsHook(adv);
       TestRefAdvertiser advertiser = new TestRefAdvertiser(repo);
diff --git a/javatests/com/google/gerrit/acceptance/git/SubmoduleSubscriptionsIT.java b/javatests/com/google/gerrit/acceptance/git/SubmoduleSubscriptionsIT.java
index 09da628..329723b7 100644
--- a/javatests/com/google/gerrit/acceptance/git/SubmoduleSubscriptionsIT.java
+++ b/javatests/com/google/gerrit/acceptance/git/SubmoduleSubscriptionsIT.java
@@ -18,10 +18,10 @@
 import static com.google.common.truth.TruthJUnit.assume;
 
 import com.google.common.collect.Iterables;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.UseClockStep;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.testing.ConfigSuite;
diff --git a/javatests/com/google/gerrit/acceptance/rest/TraceIT.java b/javatests/com/google/gerrit/acceptance/rest/TraceIT.java
index 52de5ad..d09aad8 100644
--- a/javatests/com/google/gerrit/acceptance/rest/TraceIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/TraceIT.java
@@ -28,9 +28,9 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.RestResponse;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.common.data.SubmitRecord;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
 import com.google.gerrit.extensions.events.ChangeIndexedListener;
diff --git a/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java b/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
index faaba06..a3c0295 100644
--- a/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
@@ -29,11 +29,11 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.RestSession;
 import com.google.gerrit.acceptance.TestAccount;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.GlobalCapability;
diff --git a/javatests/com/google/gerrit/acceptance/rest/binding/AccountsRestApiBindingsIT.java b/javatests/com/google/gerrit/acceptance/rest/binding/AccountsRestApiBindingsIT.java
index 8e5eaa4..eb125a0 100644
--- a/javatests/com/google/gerrit/acceptance/rest/binding/AccountsRestApiBindingsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/binding/AccountsRestApiBindingsIT.java
@@ -21,8 +21,8 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.rest.util.RestCall;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.extensions.common.ChangeInput;
diff --git a/javatests/com/google/gerrit/acceptance/rest/binding/ChangesRestApiBindingsIT.java b/javatests/com/google/gerrit/acceptance/rest/binding/ChangesRestApiBindingsIT.java
index 8a284d9..83bc3eb 100644
--- a/javatests/com/google/gerrit/acceptance/rest/binding/ChangesRestApiBindingsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/binding/ChangesRestApiBindingsIT.java
@@ -84,6 +84,7 @@
           RestCall.post("/changes/%s/rebase"),
           RestCall.post("/changes/%s/restore"),
           RestCall.post("/changes/%s/revert"),
+          RestCall.post("/changes/%s/revert_submission"),
           RestCall.get("/changes/%s/pure_revert"),
           RestCall.post("/changes/%s/submit"),
           RestCall.get("/changes/%s/submitted_together"),
diff --git a/javatests/com/google/gerrit/acceptance/rest/binding/PluginsRemoteAdminRestApiBindingsIT.java b/javatests/com/google/gerrit/acceptance/rest/binding/PluginsRemoteAdminRestApiBindingsIT.java
index d60148e..dd6eb7a 100644
--- a/javatests/com/google/gerrit/acceptance/rest/binding/PluginsRemoteAdminRestApiBindingsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/binding/PluginsRemoteAdminRestApiBindingsIT.java
@@ -18,7 +18,7 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.rest.util.RestApiCallHelper;
 import com.google.gerrit.acceptance.rest.util.RestCall;
 import com.google.gerrit.common.RawInputUtil;
diff --git a/javatests/com/google/gerrit/acceptance/rest/binding/ProjectsRestApiBindingsIT.java b/javatests/com/google/gerrit/acceptance/rest/binding/ProjectsRestApiBindingsIT.java
index f48a603..55eeaf4 100644
--- a/javatests/com/google/gerrit/acceptance/rest/binding/ProjectsRestApiBindingsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/binding/ProjectsRestApiBindingsIT.java
@@ -29,6 +29,7 @@
 import com.google.gerrit.acceptance.rest.util.RestApiCallHelper;
 import com.google.gerrit.acceptance.rest.util.RestCall;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.common.data.LabelFunction;
 import com.google.gerrit.common.data.Permission;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
@@ -73,6 +74,7 @@
           RestCall.get("/projects/%s/branches"),
           RestCall.post("/projects/%s/branches:delete"),
           RestCall.put("/projects/%s/branches/new-branch"),
+          RestCall.get("/projects/%s/labels"),
           RestCall.get("/projects/%s/tags"),
           RestCall.post("/projects/%s/tags:delete"),
           RestCall.put("/projects/%s/tags/new-tag"),
@@ -80,7 +82,9 @@
               // GET /projects/<project>/branches/<branch>/commits is not implemented
               .expectedResponseCode(SC_NOT_FOUND)
               .build(),
-          RestCall.get("/projects/%s/dashboards"));
+          RestCall.get("/projects/%s/dashboards"),
+          RestCall.put("/projects/%s/labels/new-label"),
+          RestCall.post("/projects/%s/labels/"));
 
   /**
    * Child project REST endpoints to be tested, each URL contains placeholders for the parent
@@ -158,6 +162,18 @@
   private static final ImmutableList<RestCall> COMMIT_FILE_ENDPOINTS =
       ImmutableList.of(RestCall.get("/projects/%s/commits/%s/files/%s/content"));
 
+  /**
+   * Label REST endpoints to be tested, each URL contains placeholders for the project identifier
+   * and the label name.
+   */
+  private static final ImmutableList<RestCall> LABEL_ENDPOINTS =
+      ImmutableList.of(
+          RestCall.get("/projects/%s/labels/%s"),
+          RestCall.put("/projects/%s/labels/%s"),
+
+          // Label deletion must be tested last
+          RestCall.delete("/projects/%s/labels/%s"));
+
   private static final String FILENAME = "test.txt";
   @Inject private ProjectOperations projectOperations;
 
@@ -212,6 +228,13 @@
         adminRestSession, COMMIT_FILE_ENDPOINTS, project.get(), commit, FILENAME);
   }
 
+  @Test
+  public void labelEndpoints() throws Exception {
+    String label = "Foo-Review";
+    configLabel(label, LabelFunction.NO_OP);
+    RestApiCallHelper.execute(adminRestSession, LABEL_ENDPOINTS, project.get(), label);
+  }
+
   private String createAndSubmitChange(String filename) throws Exception {
     RevCommit c =
         testRepo
diff --git a/javatests/com/google/gerrit/acceptance/rest/binding/RootCollectionsRestApiBindingsIT.java b/javatests/com/google/gerrit/acceptance/rest/binding/RootCollectionsRestApiBindingsIT.java
index 6d140c6..5573ad7 100644
--- a/javatests/com/google/gerrit/acceptance/rest/binding/RootCollectionsRestApiBindingsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/binding/RootCollectionsRestApiBindingsIT.java
@@ -20,7 +20,7 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.rest.util.RestCall;
 import org.junit.Test;
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java b/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
index 12fe263..eff98b3 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/AbstractSubmit.java
@@ -44,7 +44,6 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
@@ -52,6 +51,7 @@
 import com.google.gerrit.acceptance.TestProjectInput;
 import com.google.gerrit.acceptance.UseClockStep;
 import com.google.gerrit.acceptance.UseTimezone;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.Nullable;
@@ -1205,7 +1205,7 @@
   }
 
   @Test
-  @GerritConfig(name = "index.reindexAfterRefUpdate", value = "true")
+  @GerritConfig(name = "index.change.indexMergeable", value = "true")
   public void submitSchedulesOpenChangesOfSameBranchForReindexing() throws Throwable {
     // Create a merged change.
     PushOneCommit push =
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/ActionsIT.java b/javatests/com/google/gerrit/acceptance/rest/change/ActionsIT.java
index dda7bbd..911a04d 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/ActionsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/ActionsIT.java
@@ -63,11 +63,40 @@
     return gApi.changes().id(id).revision(1).actions();
   }
 
+  protected Map<String, ActionInfo> getChangeActions(String id) throws Exception {
+    return gApi.changes().id(id).get().actions;
+  }
+
   protected String getETag(String id) throws Exception {
     return gApi.changes().id(id).current().etag();
   }
 
   @Test
+  public void changeActionOneMergedChangeHasOnlyNormalRevert() throws Exception {
+    String changeId = createChangeWithTopic().getChangeId();
+    gApi.changes().id(changeId).current().review(ReviewInput.approve());
+    gApi.changes().id(changeId).current().submit();
+    Map<String, ActionInfo> actions = getChangeActions(changeId);
+    assertThat(actions).containsKey("revert");
+    assertThat(actions).doesNotContainKey("revert_submission");
+  }
+
+  @Test
+  public void changeActionTwoMergedChangesHaveReverts() throws Exception {
+    String changeId1 = createChangeWithTopic().getChangeId();
+    String changeId2 = createChangeWithTopic().getChangeId();
+    gApi.changes().id(changeId1).current().review(ReviewInput.approve());
+    gApi.changes().id(changeId2).current().review(ReviewInput.approve());
+    gApi.changes().id(changeId2).current().submit();
+    Map<String, ActionInfo> actions1 = getChangeActions(changeId1);
+    assertThat(actions1).containsKey("revert");
+    assertThat(actions1).containsKey("revert_submission");
+    Map<String, ActionInfo> actions2 = getChangeActions(changeId2);
+    assertThat(actions2).containsKey("revert");
+    assertThat(actions2).containsKey("revert_submission");
+  }
+
+  @Test
   public void revisionActionsOneChangePerTopicUnapproved() throws Exception {
     String changeId = createChangeWithTopic().getChangeId();
     Map<String, ActionInfo> actions = getActions(changeId);
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/CreateChangeIT.java b/javatests/com/google/gerrit/acceptance/rest/change/CreateChangeIT.java
index a1167ed..10bae39 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/CreateChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/CreateChangeIT.java
@@ -39,6 +39,7 @@
 import com.google.gerrit.extensions.api.changes.CherryPickInput;
 import com.google.gerrit.extensions.api.changes.NotifyHandling;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
+import com.google.gerrit.extensions.api.projects.BranchInput;
 import com.google.gerrit.extensions.client.ChangeStatus;
 import com.google.gerrit.extensions.client.GeneralPreferencesInfo;
 import com.google.gerrit.extensions.common.ChangeInfo;
@@ -606,6 +607,67 @@
     }
   }
 
+  @Test
+  public void createChangeWithSubmittedMergeSource() throws Exception {
+    // Provide coverage for a performance optimization in CommitsCollection#canRead.
+    BranchInput branchInput = new BranchInput();
+    String mergeTarget = "refs/heads/new-branch";
+    RevCommit startCommit = projectOperations.project(project).getHead("master");
+
+    branchInput.revision = startCommit.name();
+    branchInput.ref = mergeTarget;
+
+    gApi.projects().name(project.get()).branch(mergeTarget).create(branchInput);
+
+    PushOneCommit.Result result1 =
+        pushFactory
+            .create(
+                admin.newIdent(), testRepo, "subject1", ImmutableMap.of("file1.txt", "content 1"))
+            .to("refs/for/master");
+    result1.assertOkStatus();
+
+    testRepo.branch("HEAD").update(startCommit);
+    PushOneCommit.Result result2 =
+        pushFactory
+            .create(
+                admin.newIdent(), testRepo, "subject2", ImmutableMap.of("file2.txt", "content 2"))
+            .to("refs/for/master");
+    result2.assertOkStatus();
+
+    ReviewInput reviewInput = ReviewInput.approve().label("Code-Review", 2);
+
+    gApi.changes().id(result1.getChangeId()).revision("current").review(reviewInput);
+    gApi.changes().id(result1.getChangeId()).revision("current").submit();
+
+    gApi.changes().id(result2.getChangeId()).revision("current").review(reviewInput);
+    gApi.changes().id(result2.getChangeId()).revision("current").submit();
+
+    String mergeRev = gApi.projects().name(project.get()).branch("master").get().revision;
+    RevCommit mergeCommit = projectOperations.project(project).getHead("master");
+    assertThat(mergeCommit.getParents().length).isEqualTo(2);
+
+    testRepo.git().fetch().call();
+    testRepo.branch("HEAD").update(mergeCommit);
+    PushOneCommit.Result result3 =
+        pushFactory
+            .create(
+                admin.newIdent(), testRepo, "subject3", ImmutableMap.of("file1.txt", "content 3"))
+            .to("refs/for/master");
+    result2.assertOkStatus();
+    gApi.changes().id(result3.getChangeId()).revision("current").review(reviewInput);
+    gApi.changes().id(result3.getChangeId()).revision("current").submit();
+
+    // Now master doesn't point directly to mergeRev
+    ChangeInput in = new ChangeInput();
+    in.branch = mergeTarget;
+    in.merge = new MergeInput();
+    in.project = project.get();
+    in.merge.source = mergeRev;
+    in.subject = "propagate merge";
+
+    gApi.changes().create(in);
+  }
+
   private ChangeInput newChangeInput(ChangeStatus status) {
     ChangeInput in = new ChangeInput();
     in.project = project.get();
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/IndexChangeIT.java b/javatests/com/google/gerrit/acceptance/rest/change/IndexChangeIT.java
index 3030b02..ea3a6a0 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/IndexChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/IndexChangeIT.java
@@ -22,6 +22,7 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.TestAccount;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
@@ -58,6 +59,7 @@
   }
 
   @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "true")
   public void indexChangeAfterOwnerLosesVisibility() throws Exception {
     // Create a test group with 2 users as members
     TestAccount user2 = accountCreator.user2();
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java b/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
index 063f1a0..37b1713 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
@@ -22,10 +22,10 @@
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.GitUtil;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.LabelFunction;
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/PrivateByDefaultIT.java b/javatests/com/google/gerrit/acceptance/rest/change/PrivateByDefaultIT.java
index 1a3c10f..f5cca1b 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/PrivateByDefaultIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/PrivateByDefaultIT.java
@@ -18,8 +18,8 @@
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.extensions.api.projects.ConfigInput;
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/SuggestReviewersIT.java b/javatests/com/google/gerrit/acceptance/rest/change/SuggestReviewersIT.java
index 8e0042c..568c63b 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/SuggestReviewersIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/SuggestReviewersIT.java
@@ -27,8 +27,8 @@
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.TestAccount;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java b/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
index ae17be0..8baeffc 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/ListCachesIT.java
@@ -18,6 +18,7 @@
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.common.collect.Ordering;
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.server.restapi.config.ListCaches.CacheInfo;
@@ -26,7 +27,6 @@
 import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
-import org.eclipse.jgit.util.Base64;
 import org.junit.Test;
 
 public class ListCachesIT extends AbstractDaemonTest {
@@ -78,7 +78,7 @@
   public void listCacheNamesTextList() throws Exception {
     RestResponse r = adminRestSession.get("/config/server/caches/?format=TEXT_LIST");
     r.assertOK();
-    String result = new String(Base64.decode(r.getEntityContent()), UTF_8.name());
+    String result = new String(BaseEncoding.base64().decode(r.getEntityContent()), UTF_8);
     List<String> list = Arrays.asList(result.split("\n"));
     assertThat(list).contains("accounts");
     assertThat(list).contains("projects");
diff --git a/javatests/com/google/gerrit/acceptance/rest/config/ServerInfoIT.java b/javatests/com/google/gerrit/acceptance/rest/config/ServerInfoIT.java
index 1d87ca1..996119d 100644
--- a/javatests/com/google/gerrit/acceptance/rest/config/ServerInfoIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/config/ServerInfoIT.java
@@ -18,9 +18,9 @@
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.common.RawInputUtil;
 import com.google.gerrit.extensions.api.plugins.InstallPluginInput;
 import com.google.gerrit.extensions.client.AccountFieldName;
diff --git a/javatests/com/google/gerrit/acceptance/rest/group/GroupsIT.java b/javatests/com/google/gerrit/acceptance/rest/group/GroupsIT.java
deleted file mode 100644
index e153e561..0000000
--- a/javatests/com/google/gerrit/acceptance/rest/group/GroupsIT.java
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright (C) 2017 The Android Open Source Project
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License
-
-package com.google.gerrit.acceptance.rest.group;
-
-import static com.google.common.truth.Truth.assertThat;
-
-import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.RestResponse;
-import org.junit.Test;
-
-public class GroupsIT extends AbstractDaemonTest {
-  @Test
-  public void invalidQueryOptions() throws Exception {
-    RestResponse r = adminRestSession.put("/groups/?query=foo&query2=bar");
-    r.assertBadRequest();
-    assertThat(r.getEntityContent())
-        .isEqualTo("\"query\" and \"query2\" options are mutually exclusive");
-  }
-}
diff --git a/javatests/com/google/gerrit/acceptance/rest/group/ListGroupsIT.java b/javatests/com/google/gerrit/acceptance/rest/group/ListGroupsIT.java
new file mode 100644
index 0000000..d8132b7
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/group/ListGroupsIT.java
@@ -0,0 +1,37 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.group;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.RestResponse;
+import com.google.gerrit.extensions.common.GroupInfo;
+import com.google.gson.reflect.TypeToken;
+import java.util.Map;
+import org.junit.Test;
+
+public class ListGroupsIT extends AbstractDaemonTest {
+  @Test
+  public void listAllGroups() throws Exception {
+    RestResponse response = adminRestSession.get("/groups/");
+    response.assertOK();
+
+    Map<String, GroupInfo> groupMap =
+        newGson()
+            .fromJson(response.getReader(), new TypeToken<Map<String, GroupInfo>>() {}.getType());
+    assertThat(groupMap.keySet()).containsExactly("Administrators", "Non-Interactive Users");
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java b/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
index 91a10ca..3e9b1f6 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/AccessIT.java
@@ -604,7 +604,7 @@
   }
 
   @Test
-  public void syncCreateGroupPermission() throws Exception {
+  public void syncCreateGroupPermission_addAndRemoveCreateGroupCapability() throws Exception {
     // Grant CREATE_GROUP to Registered Users
     ProjectAccessInput accessInput = newProjectAccessInput();
     AccessSectionInfo accessSection = newAccessSectionInfo();
@@ -642,6 +642,44 @@
   }
 
   @Test
+  public void syncCreateGroupPermission_addCreateGroupCapabilityToMultipleGroups()
+      throws Exception {
+    PermissionRuleInfo pri = new PermissionRuleInfo(PermissionRuleInfo.Action.ALLOW, false);
+
+    // Grant CREATE_GROUP to Registered Users
+    ProjectAccessInput accessInput = newProjectAccessInput();
+    AccessSectionInfo accessSection = newAccessSectionInfo();
+    PermissionInfo createGroup = newPermissionInfo();
+    createGroup.rules.put(SystemGroupBackend.REGISTERED_USERS.get(), pri);
+    accessSection.permissions.put(GlobalCapability.CREATE_GROUP, createGroup);
+    accessInput.add.put(AccessSection.GLOBAL_CAPABILITIES, accessSection);
+    gApi.projects().name(allProjects.get()).access(accessInput);
+
+    // Grant CREATE_GROUP to Administrators
+    accessInput = newProjectAccessInput();
+    accessSection = newAccessSectionInfo();
+    createGroup = newPermissionInfo();
+    createGroup.rules.put(adminGroupUuid().get(), pri);
+    accessSection.permissions.put(GlobalCapability.CREATE_GROUP, createGroup);
+    accessInput.add.put(AccessSection.GLOBAL_CAPABILITIES, accessSection);
+    gApi.projects().name(allProjects.get()).access(accessInput);
+
+    // Assert that the permissions were synced from All-Projects (global) to All-Users (ref)
+    Map<String, AccessSectionInfo> local = gApi.projects().name("All-Users").access().local;
+    assertThat(local).isNotNull();
+    assertThat(local).containsKey(RefNames.REFS_GROUPS + "*");
+    Map<String, PermissionInfo> permissions = local.get(RefNames.REFS_GROUPS + "*").permissions;
+    assertThat(permissions).hasSize(2);
+    // READ is the default permission and should be preserved by the syncer
+    assertThat(permissions.keySet()).containsExactly(Permission.READ, Permission.CREATE);
+    Map<String, PermissionRuleInfo> rules = permissions.get(Permission.CREATE).rules;
+    assertThat(rules.keySet())
+        .containsExactly(SystemGroupBackend.REGISTERED_USERS.get(), adminGroupUuid().get());
+    assertThat(rules.get(SystemGroupBackend.REGISTERED_USERS.get())).isEqualTo(pri);
+    assertThat(rules.get(adminGroupUuid().get())).isEqualTo(pri);
+  }
+
+  @Test
   public void addAccessSectionForInvalidRef() throws Exception {
     ProjectAccessInput accessInput = newProjectAccessInput();
     AccessSectionInfo accessSectionInfo = createDefaultAccessSectionInfo();
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/BUILD b/javatests/com/google/gerrit/acceptance/rest/project/BUILD
index e082559..b50a12b 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/BUILD
+++ b/javatests/com/google/gerrit/acceptance/rest/project/BUILD
@@ -6,6 +6,7 @@
     group = f[:f.index(".")],
     labels = ["rest"],
     deps = [
+        ":labelassert",
         ":project",
         ":push_tag_util",
         ":refassert",
@@ -14,6 +15,19 @@
 ) for f in glob(["*IT.java"])]
 
 java_library(
+    name = "labelassert",
+    srcs = [
+        "LabelAssert.java",
+    ],
+    deps = [
+        "//java/com/google/gerrit/common:server",
+        "//java/com/google/gerrit/extensions:api",
+        "//java/com/google/gerrit/server",
+        "//lib/truth",
+    ],
+)
+
+java_library(
     name = "refassert",
     srcs = [
         "RefAssert.java",
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/CreateLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/CreateLabelIT.java
new file mode 100644
index 0000000..57a1e56
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/CreateLabelIT.java
@@ -0,0 +1,611 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allow;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.inject.Inject;
+import org.junit.Test;
+
+@NoHttpd
+public class CreateLabelIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject private ProjectOperations projectOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () ->
+                gApi.projects()
+                    .name(project.get())
+                    .label("Foo-Review")
+                    .create(new LabelDefinitionInput()));
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    projectOperations
+        .project(project)
+        .forUpdate()
+        .add(allow(Permission.READ).ref(RefNames.REFS_CONFIG).group(REGISTERED_USERS))
+        .update();
+
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () ->
+                gApi.projects()
+                    .name(project.get())
+                    .label("Foo-Review")
+                    .create(new LabelDefinitionInput()));
+    assertThat(thrown).hasMessageThat().contains("write refs/meta/config not permitted");
+  }
+
+  @Test
+  public void cannotCreateLabelIfNameDoesntMatch() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "Foo";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Bar").create(input));
+    assertThat(thrown).hasMessageThat().contains("name in input must match name in URL");
+  }
+
+  @Test
+  public void cannotCreateLabelWithNameThatIsAlreadyInUse() throws Exception {
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () ->
+                gApi.projects()
+                    .name(allProjects.get())
+                    .label("Code-Review")
+                    .create(new LabelDefinitionInput()));
+    assertThat(thrown).hasMessageThat().contains("label Code-Review already exists");
+  }
+
+  @Test
+  public void cannotCreateLabelWithNameThatConflicts() throws Exception {
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () ->
+                gApi.projects()
+                    .name(allProjects.get())
+                    .label("code-review")
+                    .create(new LabelDefinitionInput()));
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("label code-review conflicts with existing label Code-Review");
+  }
+
+  @Test
+  public void cannotCreateLabelWithInvalidName() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("INVALID_NAME").create(input));
+    assertThat(thrown).hasMessageThat().contains("invalid name: INVALID_NAME");
+  }
+
+  @Test
+  public void cannotCreateLabelWithoutValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("values are required");
+
+    input.values = ImmutableMap.of();
+    thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("values are required");
+  }
+
+  @Test
+  public void cannotCreateLabelWithInvalidValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("invalidValue", "description");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("invalid value: invalidValue");
+  }
+
+  @Test
+  public void cannotCreateLabelWithValuesThatHaveEmptyDescription() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("description for value '+1' cannot be empty");
+  }
+
+  @Test
+  public void cannotCreateLabelWithDuplicateValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Positive values can be specified as '<value>' or '+<value>'.
+    input.values =
+        ImmutableMap.of(
+            "+1", "Looks Good", "1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("duplicate value: 1");
+  }
+
+  @Test
+  public void cannotCreateLabelWithInvalidDefaultValue() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+    input.defaultValue = 5;
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("invalid default value: " + input.defaultValue);
+  }
+
+  @Test
+  public void cannotCreateLabelWithUnknownFunction() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+    input.function = "UnknownFuction";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("unknown function: " + input.function);
+  }
+
+  @Test
+  public void cannotCreateLabelWithInvalidBranch() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+    input.branches = ImmutableList.of("refs heads master");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(project.get()).label("Foo").create(input));
+    assertThat(thrown).hasMessageThat().contains("invalid branch: refs heads master");
+  }
+
+  @Test
+  public void createWithNameAndValuesOnly() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+
+    assertThat(createdLabel.name).isEqualTo("Foo");
+    assertThat(createdLabel.projectName).isEqualTo(project.get());
+    assertThat(createdLabel.function).isEqualTo(LabelFunction.MAX_WITH_BLOCK.getFunctionName());
+    assertThat(createdLabel.values).containsExactlyEntriesIn(input.values);
+    assertThat(createdLabel.defaultValue).isEqualTo(0);
+    assertThat(createdLabel.branches).isNull();
+    assertThat(createdLabel.canOverride).isTrue();
+    assertThat(createdLabel.copyAnyScore).isNull();
+    assertThat(createdLabel.copyMinScore).isNull();
+    assertThat(createdLabel.copyMaxScore).isNull();
+    assertThat(createdLabel.copyAllScoresIfNoChange).isTrue();
+    assertThat(createdLabel.copyAllScoresIfNoCodeChange).isNull();
+    assertThat(createdLabel.copyAllScoresOnTrivialRebase).isNull();
+    assertThat(createdLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+    assertThat(createdLabel.allowPostSubmit).isTrue();
+    assertThat(createdLabel.ignoreSelfApproval).isNull();
+  }
+
+  @Test
+  public void createWithFunction() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.function = LabelFunction.NO_OP.getFunctionName();
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+
+    assertThat(createdLabel.function).isEqualTo(LabelFunction.NO_OP.getFunctionName());
+  }
+
+  @Test
+  public void functionEmptyAfterTrim() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.function = " ";
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+
+    assertThat(createdLabel.function).isEqualTo(LabelFunction.MAX_WITH_BLOCK.getFunctionName());
+  }
+
+  @Test
+  public void valuesAndDescriptionsAreTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Positive values can be specified as '<value>' or '+<value>'.
+    input.values =
+        ImmutableMap.of(
+            " 2 ",
+            " Looks Very Good ",
+            " +1 ",
+            " Looks Good ",
+            " 0 ",
+            " Don't Know ",
+            " -1 ",
+            " Looks Bad ",
+            " -2 ",
+            " Looks Very Bad ");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+    assertThat(createdLabel.values)
+        .containsExactly(
+            "+2", "Looks Very Good",
+            "+1", "Looks Good",
+            " 0", "Don't Know",
+            "-1", "Looks Bad",
+            "-2", "Looks Very Bad");
+  }
+
+  @Test
+  public void createWithDefaultValue() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.defaultValue = 1;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+
+    assertThat(createdLabel.defaultValue).isEqualTo(input.defaultValue);
+  }
+
+  @Test
+  public void createWithBranches() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    // Branches can be full ref, ref pattern or regular expression.
+    input.branches =
+        ImmutableList.of("refs/heads/master", "refs/heads/foo/*", "^refs/heads/stable-.*");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+    assertThat(createdLabel.branches).containsExactlyElementsIn(input.branches);
+  }
+
+  @Test
+  public void branchesAreTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.branches =
+        ImmutableList.of(" refs/heads/master ", " refs/heads/foo/* ", " ^refs/heads/stable-.* ");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+    assertThat(createdLabel.branches)
+        .containsExactly("refs/heads/master", "refs/heads/foo/*", "^refs/heads/stable-.*");
+  }
+
+  @Test
+  public void emptyBranchesAreIgnored() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.branches = ImmutableList.of("refs/heads/master", "", " ");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+    assertThat(createdLabel.branches).containsExactly("refs/heads/master");
+  }
+
+  @Test
+  public void branchesAreAutomaticallyPrefixedWithRefsHeads() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.branches = ImmutableList.of("master", "refs/meta/config");
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("Foo").create(input).get();
+    assertThat(createdLabel.branches).containsExactly("refs/heads/master", "refs/meta/config");
+  }
+
+  @Test
+  public void createWithCanOverride() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.canOverride = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.canOverride).isTrue();
+  }
+
+  @Test
+  public void createWithoutCanOverride() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.canOverride = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.canOverride).isNull();
+  }
+
+  @Test
+  public void createWithCopyAnyScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAnyScore = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAnyScore).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyAnyScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAnyScore = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAnyScore).isNull();
+  }
+
+  @Test
+  public void createWithCopyMinScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyMinScore = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyMinScore).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyMinScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyMinScore = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyMinScore).isNull();
+  }
+
+  @Test
+  public void createWithCopyMaxScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyMaxScore = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyMaxScore).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyMaxScore() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyMaxScore = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyMaxScore).isNull();
+  }
+
+  @Test
+  public void createWithCopyAllScoresIfNoChange() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresIfNoChange = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresIfNoChange).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyAllScoresIfNoChange() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresIfNoChange = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresIfNoChange).isNull();
+  }
+
+  @Test
+  public void createWithCopyAllScoresIfNoCodeChange() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresIfNoCodeChange = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresIfNoCodeChange).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyAllScoresIfNoCodeChange() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresIfNoCodeChange = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresIfNoCodeChange).isNull();
+  }
+
+  @Test
+  public void createWithCopyAllScoresOnTrivialRebase() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresOnTrivialRebase = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresOnTrivialRebase).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyAllScoresOnTrivialRebase() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresOnTrivialRebase = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresOnTrivialRebase).isNull();
+  }
+
+  @Test
+  public void createWithCopyAllScoresOnMergeFirstParentUpdate() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresOnMergeFirstParentUpdate = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresOnMergeFirstParentUpdate).isTrue();
+  }
+
+  @Test
+  public void createWithoutCopyAllScoresOnMergeFirstParentUpdate() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.copyAllScoresOnMergeFirstParentUpdate = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+  }
+
+  @Test
+  public void createWithAllowPostSubmit() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.allowPostSubmit = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.allowPostSubmit).isTrue();
+  }
+
+  @Test
+  public void createWithoutAllowPostSubmit() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.allowPostSubmit = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.allowPostSubmit).isNull();
+  }
+
+  @Test
+  public void createWithIgnoreSelfApproval() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.ignoreSelfApproval = true;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.ignoreSelfApproval).isTrue();
+  }
+
+  @Test
+  public void createWithoutIgnoreSelfApproval() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.ignoreSelfApproval = false;
+
+    LabelDefinitionInfo createdLabel =
+        gApi.projects().name(project.get()).label("foo").create(input).get();
+    assertThat(createdLabel.ignoreSelfApproval).isNull();
+  }
+
+  @Test
+  public void defaultCommitMessage() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    gApi.projects().name(project.get()).label("Foo").create(input);
+    assertThat(projectOperations.project(project).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Update label");
+  }
+
+  @Test
+  public void withCommitMessage() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.commitMessage = "Add Foo Label";
+    gApi.projects().name(project.get()).label("Foo").create(input);
+    assertThat(projectOperations.project(project).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo(input.commitMessage);
+  }
+
+  @Test
+  public void commitMessageIsTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+    input.commitMessage = " Add Foo Label ";
+    gApi.projects().name(project.get()).label("Foo").create(input);
+    assertThat(projectOperations.project(project).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Add Foo Label");
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/CreateProjectIT.java b/javatests/com/google/gerrit/acceptance/rest/project/CreateProjectIT.java
index 6b2baa7..0ba4f16 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/CreateProjectIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/CreateProjectIT.java
@@ -30,9 +30,9 @@
 import com.google.common.collect.Sets;
 import com.google.common.net.HttpHeaders;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.acceptance.UseLocalDisk;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.GlobalCapability;
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/DeleteLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/DeleteLabelIT.java
new file mode 100644
index 0000000..c916285
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/DeleteLabelIT.java
@@ -0,0 +1,108 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allow;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.inject.Inject;
+import org.junit.Test;
+
+public class DeleteLabelIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject private ProjectOperations projectOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").delete());
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    projectOperations
+        .project(allProjects)
+        .forUpdate()
+        .add(allow(Permission.READ).ref(RefNames.REFS_CONFIG).group(REGISTERED_USERS))
+        .update();
+
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").delete());
+    assertThat(thrown).hasMessageThat().contains("write refs/meta/config not permitted");
+  }
+
+  @Test
+  public void nonExisting() throws Exception {
+    ResourceNotFoundException thrown =
+        assertThrows(
+            ResourceNotFoundException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Non-Existing-Review").delete());
+    assertThat(thrown).hasMessageThat().contains("Not found: Non-Existing-Review");
+  }
+
+  @Test
+  public void delete() throws Exception {
+    gApi.projects().name(allProjects.get()).label("Code-Review").delete();
+
+    ResourceNotFoundException thrown =
+        assertThrows(
+            ResourceNotFoundException.class,
+            () -> gApi.projects().name(project.get()).label("Code-Review").get());
+    assertThat(thrown).hasMessageThat().contains("Not found: Code-Review");
+  }
+
+  @Test
+  public void defaultCommitMessage() throws Exception {
+    gApi.projects().name(allProjects.get()).label("Code-Review").delete();
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Delete label");
+  }
+
+  @Test
+  public void withCommitMessage() throws Exception {
+    gApi.projects().name(allProjects.get()).label("Code-Review").delete("Delete Code-Review label");
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Delete Code-Review label");
+  }
+
+  @Test
+  public void commitMessageIsTrimmed() throws Exception {
+    gApi.projects()
+        .name(allProjects.get())
+        .label("Code-Review")
+        .delete(" Delete Code-Review label ");
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Delete Code-Review label");
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java
new file mode 100644
index 0000000..9f98490
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java
@@ -0,0 +1,154 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.inject.Inject;
+import org.junit.Test;
+
+@NoHttpd
+public class GetLabelIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").get());
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").get());
+    assertThat(thrown).hasMessageThat().contains("read refs/meta/config not permitted");
+  }
+
+  @Test
+  public void notFound() throws Exception {
+    ResourceNotFoundException thrown =
+        assertThrows(
+            ResourceNotFoundException.class,
+            () -> gApi.projects().name(project.get()).label("Foo-Review").get());
+    assertThat(thrown).hasMessageThat().contains("Not found: Foo-Review");
+  }
+
+  @Test
+  public void allProjectsCodeReviewLabel() throws Exception {
+    LabelDefinitionInfo codeReviewLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").get();
+    LabelAssert.assertCodeReviewLabel(codeReviewLabel);
+  }
+
+  @Test
+  public void labelWithDefaultValue() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // set default value
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setDefaultValue((short) 1);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("foo").get();
+    assertThat(fooLabel.defaultValue).isEqualTo(1);
+  }
+
+  @Test
+  public void labelLimitedToBranches() throws Exception {
+    configLabel(
+        "foo", LabelFunction.NO_OP, ImmutableList.of("refs/heads/master", "^refs/heads/stable-.*"));
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("foo").get();
+    assertThat(fooLabel.branches).containsExactly("refs/heads/master", "^refs/heads/stable-.*");
+  }
+
+  @Test
+  public void labelWithoutRules() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // unset rules which are enabled by default
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCanOverride(false);
+      labelType.setCopyAllScoresIfNoChange(false);
+      labelType.setAllowPostSubmit(false);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("foo").get();
+    assertThat(fooLabel.canOverride).isNull();
+    assertThat(fooLabel.copyAnyScore).isNull();
+    assertThat(fooLabel.copyMinScore).isNull();
+    assertThat(fooLabel.copyMaxScore).isNull();
+    assertThat(fooLabel.copyAllScoresIfNoChange).isNull();
+    assertThat(fooLabel.copyAllScoresIfNoCodeChange).isNull();
+    assertThat(fooLabel.copyAllScoresOnTrivialRebase).isNull();
+    assertThat(fooLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+    assertThat(fooLabel.allowPostSubmit).isNull();
+    assertThat(fooLabel.ignoreSelfApproval).isNull();
+  }
+
+  @Test
+  public void labelWithAllRules() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // set rules which are not enabled by default
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAnyScore(true);
+      labelType.setCopyMinScore(true);
+      labelType.setCopyMaxScore(true);
+      labelType.setCopyAllScoresIfNoCodeChange(true);
+      labelType.setCopyAllScoresOnTrivialRebase(true);
+      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
+      labelType.setIgnoreSelfApproval(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("foo").get();
+    assertThat(fooLabel.canOverride).isTrue();
+    assertThat(fooLabel.copyAnyScore).isTrue();
+    assertThat(fooLabel.copyMinScore).isTrue();
+    assertThat(fooLabel.copyMaxScore).isTrue();
+    assertThat(fooLabel.copyAllScoresIfNoChange).isTrue();
+    assertThat(fooLabel.copyAllScoresIfNoCodeChange).isTrue();
+    assertThat(fooLabel.copyAllScoresOnTrivialRebase).isTrue();
+    assertThat(fooLabel.copyAllScoresOnMergeFirstParentUpdate).isTrue();
+    assertThat(fooLabel.allowPostSubmit).isTrue();
+    assertThat(fooLabel.ignoreSelfApproval).isTrue();
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/LabelAssert.java b/javatests/com/google/gerrit/acceptance/rest/project/LabelAssert.java
new file mode 100644
index 0000000..7998ecb
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/LabelAssert.java
@@ -0,0 +1,55 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.server.config.AllProjectsNameProvider;
+
+public class LabelAssert {
+  public static void assertCodeReviewLabel(LabelDefinitionInfo codeReviewLabel) {
+    assertThat(codeReviewLabel.name).isEqualTo("Code-Review");
+    assertThat(codeReviewLabel.projectName).isEqualTo(AllProjectsNameProvider.DEFAULT);
+    assertThat(codeReviewLabel.function).isEqualTo(LabelFunction.MAX_WITH_BLOCK.getFunctionName());
+    assertThat(codeReviewLabel.values)
+        .containsExactly(
+            "+2",
+            "Looks good to me, approved",
+            "+1",
+            "Looks good to me, but someone else must approve",
+            " 0",
+            "No score",
+            "-1",
+            "I would prefer this is not merged as is",
+            "-2",
+            "This shall not be merged");
+    assertThat(codeReviewLabel.defaultValue).isEqualTo(0);
+    assertThat(codeReviewLabel.branches).isNull();
+    assertThat(codeReviewLabel.canOverride).isTrue();
+    assertThat(codeReviewLabel.copyAnyScore).isNull();
+    assertThat(codeReviewLabel.copyMinScore).isTrue();
+    assertThat(codeReviewLabel.copyMaxScore).isNull();
+    assertThat(codeReviewLabel.copyAllScoresIfNoChange).isTrue();
+    assertThat(codeReviewLabel.copyAllScoresIfNoCodeChange).isNull();
+    assertThat(codeReviewLabel.copyAllScoresOnTrivialRebase).isTrue();
+    assertThat(codeReviewLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+    assertThat(codeReviewLabel.allowPostSubmit).isTrue();
+    assertThat(codeReviewLabel.ignoreSelfApproval).isNull();
+  }
+
+  private LabelAssert() {}
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java b/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java
new file mode 100644
index 0000000..d2539e5
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java
@@ -0,0 +1,268 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allow;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+import static java.util.stream.Collectors.toList;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Iterables;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.Project;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.inject.Inject;
+import java.util.List;
+import org.junit.Test;
+
+@NoHttpd
+public class ListLabelsIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject private ProjectOperations projectOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(AuthException.class, () -> gApi.projects().name(project.get()).labels().get());
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(AuthException.class, () -> gApi.projects().name(project.get()).labels().get());
+    assertThat(thrown).hasMessageThat().contains("read refs/meta/config not permitted");
+  }
+
+  @Test
+  public void noLabels() throws Exception {
+    assertThat(gApi.projects().name(project.get()).labels().get()).isEmpty();
+  }
+
+  @Test
+  public void allProjectsLabels() throws Exception {
+    List<LabelDefinitionInfo> labels = gApi.projects().name(allProjects.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("Code-Review");
+
+    LabelDefinitionInfo codeReviewLabel = Iterables.getOnlyElement(labels);
+    LabelAssert.assertCodeReviewLabel(codeReviewLabel);
+  }
+
+  @Test
+  public void labelsAreSortedByName() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    configLabel("bar", LabelFunction.NO_OP);
+    configLabel("baz", LabelFunction.NO_OP);
+
+    List<LabelDefinitionInfo> labels = gApi.projects().name(project.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("bar", "baz", "foo").inOrder();
+  }
+
+  @Test
+  public void labelWithDefaultValue() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // set default value
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setDefaultValue((short) 1);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    List<LabelDefinitionInfo> labels = gApi.projects().name(project.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("foo");
+
+    LabelDefinitionInfo fooLabel = Iterables.getOnlyElement(labels);
+    assertThat(fooLabel.defaultValue).isEqualTo(1);
+  }
+
+  @Test
+  public void labelLimitedToBranches() throws Exception {
+    configLabel(
+        "foo", LabelFunction.NO_OP, ImmutableList.of("refs/heads/master", "^refs/heads/stable-.*"));
+
+    List<LabelDefinitionInfo> labels = gApi.projects().name(project.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("foo");
+
+    LabelDefinitionInfo fooLabel = Iterables.getOnlyElement(labels);
+    assertThat(fooLabel.branches).containsExactly("refs/heads/master", "^refs/heads/stable-.*");
+  }
+
+  @Test
+  public void labelWithoutRules() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // unset rules which are enabled by default
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCanOverride(false);
+      labelType.setCopyAllScoresIfNoChange(false);
+      labelType.setAllowPostSubmit(false);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    List<LabelDefinitionInfo> labels = gApi.projects().name(project.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("foo");
+
+    LabelDefinitionInfo fooLabel = Iterables.getOnlyElement(labels);
+    assertThat(fooLabel.canOverride).isNull();
+    assertThat(fooLabel.copyAnyScore).isNull();
+    assertThat(fooLabel.copyMinScore).isNull();
+    assertThat(fooLabel.copyMaxScore).isNull();
+    assertThat(fooLabel.copyAllScoresIfNoChange).isNull();
+    assertThat(fooLabel.copyAllScoresIfNoCodeChange).isNull();
+    assertThat(fooLabel.copyAllScoresOnTrivialRebase).isNull();
+    assertThat(fooLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+    assertThat(fooLabel.allowPostSubmit).isNull();
+    assertThat(fooLabel.ignoreSelfApproval).isNull();
+  }
+
+  @Test
+  public void labelWithAllRules() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+
+    // set rules which are not enabled by default
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAnyScore(true);
+      labelType.setCopyMinScore(true);
+      labelType.setCopyMaxScore(true);
+      labelType.setCopyAllScoresIfNoCodeChange(true);
+      labelType.setCopyAllScoresOnTrivialRebase(true);
+      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
+      labelType.setIgnoreSelfApproval(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+
+    List<LabelDefinitionInfo> labels = gApi.projects().name(project.get()).labels().get();
+    assertThat(labelNames(labels)).containsExactly("foo");
+
+    LabelDefinitionInfo fooLabel = Iterables.getOnlyElement(labels);
+    assertThat(fooLabel.canOverride).isTrue();
+    assertThat(fooLabel.copyAnyScore).isTrue();
+    assertThat(fooLabel.copyMinScore).isTrue();
+    assertThat(fooLabel.copyMaxScore).isTrue();
+    assertThat(fooLabel.copyAllScoresIfNoChange).isTrue();
+    assertThat(fooLabel.copyAllScoresIfNoCodeChange).isTrue();
+    assertThat(fooLabel.copyAllScoresOnTrivialRebase).isTrue();
+    assertThat(fooLabel.copyAllScoresOnMergeFirstParentUpdate).isTrue();
+    assertThat(fooLabel.allowPostSubmit).isTrue();
+    assertThat(fooLabel.ignoreSelfApproval).isTrue();
+  }
+
+  @Test
+  public void withInheritedLabelsNotAllowed() throws Exception {
+    projectOperations
+        .project(project)
+        .forUpdate()
+        .add(allow(Permission.READ).ref(RefNames.REFS_CONFIG).group(REGISTERED_USERS))
+        .update();
+
+    requestScopeOperations.setApiUser(user.id());
+
+    // can list labels without inheritance
+    gApi.projects().name(project.get()).labels().get();
+
+    // cannot list labels with inheritance
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(project.get()).labels().withInherited(true).get());
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("All-Projects: read refs/meta/config not permitted");
+  }
+
+  @Test
+  public void inheritedLabelsOnly() throws Exception {
+    List<LabelDefinitionInfo> labels =
+        gApi.projects().name(project.get()).labels().withInherited(true).get();
+    assertThat(labelNames(labels)).containsExactly("Code-Review");
+
+    LabelDefinitionInfo codeReviewLabel = Iterables.getOnlyElement(labels);
+    LabelAssert.assertCodeReviewLabel(codeReviewLabel);
+  }
+
+  @Test
+  public void withInheritedLabels() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    configLabel("bar", LabelFunction.NO_OP);
+    configLabel("baz", LabelFunction.NO_OP);
+
+    List<LabelDefinitionInfo> labels =
+        gApi.projects().name(project.get()).labels().withInherited(true).get();
+    assertThat(labelNames(labels)).containsExactly("Code-Review", "bar", "baz", "foo").inOrder();
+
+    LabelAssert.assertCodeReviewLabel(labels.get(0));
+    assertThat(labels.get(1).name).isEqualTo("bar");
+    assertThat(labels.get(1).projectName).isEqualTo(project.get());
+    assertThat(labels.get(2).name).isEqualTo("baz");
+    assertThat(labels.get(2).projectName).isEqualTo(project.get());
+    assertThat(labels.get(3).name).isEqualTo("foo");
+    assertThat(labels.get(3).projectName).isEqualTo(project.get());
+  }
+
+  @Test
+  public void withInheritedLabelsAndOverriddenLabel() throws Exception {
+    configLabel("Code-Review", LabelFunction.NO_OP);
+
+    List<LabelDefinitionInfo> labels =
+        gApi.projects().name(project.get()).labels().withInherited(true).get();
+    assertThat(labelNames(labels)).containsExactly("Code-Review", "Code-Review");
+
+    LabelAssert.assertCodeReviewLabel(labels.get(0));
+    assertThat(labels.get(1).name).isEqualTo("Code-Review");
+    assertThat(labels.get(1).projectName).isEqualTo(project.get());
+    assertThat(labels.get(1).function).isEqualTo(LabelFunction.NO_OP.getFunctionName());
+  }
+
+  @Test
+  public void withInheritedLabelsFromMultipleParents() throws Exception {
+    configLabel(project, "foo", LabelFunction.NO_OP);
+
+    Project.NameKey childProject =
+        projectOperations.newProject().name("child").parent(project).create();
+    configLabel(childProject, "bar", LabelFunction.NO_OP);
+
+    List<LabelDefinitionInfo> labels =
+        gApi.projects().name(childProject.get()).labels().withInherited(true).get();
+    assertThat(labelNames(labels)).containsExactly("Code-Review", "foo", "bar").inOrder();
+
+    LabelAssert.assertCodeReviewLabel(labels.get(0));
+    assertThat(labels.get(1).name).isEqualTo("foo");
+    assertThat(labels.get(1).projectName).isEqualTo(project.get());
+    assertThat(labels.get(2).name).isEqualTo("bar");
+    assertThat(labels.get(2).projectName).isEqualTo(childProject.get());
+  }
+
+  private static List<String> labelNames(List<LabelDefinitionInfo> labels) {
+    return labels.stream().map(l -> l.name).collect(toList());
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/ListProjectsIT.java b/javatests/com/google/gerrit/acceptance/rest/project/ListProjectsIT.java
index 29d3eb2..bb08267 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/ListProjectsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/ListProjectsIT.java
@@ -26,10 +26,10 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Iterables;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.Sandboxed;
 import com.google.gerrit.acceptance.TestProjectInput;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.Permission;
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/PostLabelsIT.java b/javatests/com/google/gerrit/acceptance/rest/project/PostLabelsIT.java
new file mode 100644
index 0000000..9e6b051
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/PostLabelsIT.java
@@ -0,0 +1,456 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allow;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.common.BatchLabelInput;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.gerrit.extensions.restapi.UnprocessableEntityException;
+import com.google.gerrit.server.restapi.project.PostLabels;
+import com.google.inject.Inject;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.junit.Test;
+
+/** Tests for the {@link PostLabels} REST endpoint. */
+public class PostLabelsIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject private ProjectOperations projectOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).labels(new BatchLabelInput()));
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    projectOperations
+        .project(allProjects)
+        .forUpdate()
+        .add(allow(Permission.READ).ref(RefNames.REFS_CONFIG).group(REGISTERED_USERS))
+        .update();
+
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () -> gApi.projects().name(allProjects.get()).labels(new BatchLabelInput()));
+    assertThat(thrown).hasMessageThat().contains("write refs/meta/config not permitted");
+  }
+
+  @Test
+  public void deleteNonExistingLabel() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo");
+
+    UnprocessableEntityException thrown =
+        assertThrows(
+            UnprocessableEntityException.class,
+            () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo not found");
+  }
+
+  @Test
+  public void deleteLabels() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+    configLabel("Bar", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).labels().get()).isNotEmpty();
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo", "Bar");
+    gApi.projects().name(project.get()).labels(input);
+    assertThat(gApi.projects().name(project.get()).labels().get()).isEmpty();
+  }
+
+  @Test
+  public void deleteLabels_labelNamesAreTrimmed() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+    configLabel("Bar", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).labels().get()).isNotEmpty();
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of(" Foo ", " Bar ");
+    gApi.projects().name(project.get()).labels(input);
+    assertThat(gApi.projects().name(project.get()).labels().get()).isEmpty();
+  }
+
+  @Test
+  public void cannotDeleteTheSameLabelTwice() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo", "Foo");
+
+    UnprocessableEntityException thrown =
+        assertThrows(
+            UnprocessableEntityException.class,
+            () -> gApi.projects().name(project.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo not found");
+  }
+
+  @Test
+  public void cannotCreateLabelWithNameThatIsAlreadyInUse() throws Exception {
+    LabelDefinitionInput labelInput = new LabelDefinitionInput();
+    labelInput.name = "Code-Review";
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(labelInput);
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Code-Review already exists");
+  }
+
+  @Test
+  public void cannotCreateTwoLabelsWithTheSameName() throws Exception {
+    LabelDefinitionInput fooInput = new LabelDefinitionInput();
+    fooInput.name = "Foo";
+    fooInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(fooInput, fooInput);
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(project.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo already exists");
+  }
+
+  @Test
+  public void cannotCreateTwoLabelsWithNamesThatAreTheSameAfterTrim() throws Exception {
+    LabelDefinitionInput foo1Input = new LabelDefinitionInput();
+    foo1Input.name = "Foo";
+    foo1Input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput foo2Input = new LabelDefinitionInput();
+    foo2Input.name = " Foo ";
+    foo2Input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(foo1Input, foo2Input);
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(project.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo already exists");
+  }
+
+  @Test
+  public void cannotCreateTwoLabelsWithConflictingNames() throws Exception {
+    LabelDefinitionInput foo1Input = new LabelDefinitionInput();
+    foo1Input.name = "Foo";
+    foo1Input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput foo2Input = new LabelDefinitionInput();
+    foo2Input.name = "foo";
+    foo2Input.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(foo1Input, foo2Input);
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(project.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label foo conflicts with existing label Foo");
+  }
+
+  @Test
+  public void createLabels() throws Exception {
+    LabelDefinitionInput fooInput = new LabelDefinitionInput();
+    fooInput.name = "Foo";
+    fooInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput barInput = new LabelDefinitionInput();
+    barInput.name = "Bar";
+    barInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(fooInput, barInput);
+
+    gApi.projects().name(allProjects.get()).labels(input);
+    assertThat(gApi.projects().name(allProjects.get()).label("Foo").get()).isNotNull();
+    assertThat(gApi.projects().name(allProjects.get()).label("Bar").get()).isNotNull();
+  }
+
+  @Test
+  public void createLabels_labelNamesAreTrimmed() throws Exception {
+    LabelDefinitionInput fooInput = new LabelDefinitionInput();
+    fooInput.name = " Foo ";
+    fooInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput barInput = new LabelDefinitionInput();
+    barInput.name = " Bar ";
+    barInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(fooInput, barInput);
+
+    gApi.projects().name(allProjects.get()).labels(input);
+    assertThat(gApi.projects().name(allProjects.get()).label("Foo").get()).isNotNull();
+    assertThat(gApi.projects().name(allProjects.get()).label("Bar").get()).isNotNull();
+  }
+
+  @Test
+  public void cannotCreateLabelWithoutName() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(new LabelDefinitionInput());
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class, () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label name is required for new label");
+  }
+
+  @Test
+  public void cannotSetCommitMessageOnLabelDefinitionInputForCreate() throws Exception {
+    LabelDefinitionInput labelInput = new LabelDefinitionInput();
+    labelInput.name = "Foo";
+    labelInput.commitMessage = "Create Label Foo";
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(labelInput);
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class, () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("commit message on label definition input not supported");
+  }
+
+  @Test
+  public void updateNonExistingLabel() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.update = ImmutableMap.of("Foo", new LabelDefinitionInput());
+
+    UnprocessableEntityException thrown =
+        assertThrows(
+            UnprocessableEntityException.class,
+            () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo not found");
+  }
+
+  @Test
+  public void updateLabels() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+    configLabel("Bar", LabelFunction.NO_OP);
+
+    LabelDefinitionInput fooUpdate = new LabelDefinitionInput();
+    fooUpdate.function = LabelFunction.MAX_WITH_BLOCK.getFunctionName();
+    LabelDefinitionInput barUpdate = new LabelDefinitionInput();
+    barUpdate.name = "Baz";
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.update = ImmutableMap.of("Foo", fooUpdate, "Bar", barUpdate);
+
+    gApi.projects().name(project.get()).labels(input);
+
+    assertThat(gApi.projects().name(project.get()).label("Foo").get().function)
+        .isEqualTo(fooUpdate.function);
+    assertThat(gApi.projects().name(project.get()).label("Baz").get()).isNotNull();
+    assertThrows(
+        ResourceNotFoundException.class,
+        () -> gApi.projects().name(project.get()).label("Bar").get());
+  }
+
+  @Test
+  public void updateLabels_labelNamesAreTrimmed() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+    configLabel("Bar", LabelFunction.NO_OP);
+
+    LabelDefinitionInput fooUpdate = new LabelDefinitionInput();
+    fooUpdate.function = LabelFunction.MAX_WITH_BLOCK.getFunctionName();
+    LabelDefinitionInput barUpdate = new LabelDefinitionInput();
+    barUpdate.name = "Baz";
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.update = ImmutableMap.of(" Foo ", fooUpdate, " Bar ", barUpdate);
+
+    gApi.projects().name(project.get()).labels(input);
+
+    assertThat(gApi.projects().name(project.get()).label("Foo").get().function)
+        .isEqualTo(fooUpdate.function);
+    assertThat(gApi.projects().name(project.get()).label("Baz").get()).isNotNull();
+    assertThrows(
+        ResourceNotFoundException.class,
+        () -> gApi.projects().name(project.get()).label("Bar").get());
+  }
+
+  @Test
+  public void cannotSetCommitMessageOnLabelDefinitionInputForUpdate() throws Exception {
+    LabelDefinitionInput labelInput = new LabelDefinitionInput();
+    labelInput.commitMessage = "Update label";
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.update = ImmutableMap.of("Code-Review", labelInput);
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class, () -> gApi.projects().name(allProjects.get()).labels(input));
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("commit message on label definition input not supported");
+  }
+
+  @Test
+  public void deleteAndRecreateLabel() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+
+    LabelDefinitionInput fooInput = new LabelDefinitionInput();
+    fooInput.name = "Foo";
+    fooInput.function = LabelFunction.MAX_NO_BLOCK.getFunctionName();
+    fooInput.values = ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo");
+    input.create = ImmutableList.of(fooInput);
+
+    gApi.projects().name(project.get()).labels(input);
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("Foo").get();
+    assertThat(fooLabel.function).isEqualTo(fooInput.function);
+  }
+
+  @Test
+  public void deleteRecreateAndUpdateLabel() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+
+    LabelDefinitionInput fooCreateInput = new LabelDefinitionInput();
+    fooCreateInput.name = "Foo";
+    fooCreateInput.function = LabelFunction.MAX_NO_BLOCK.getFunctionName();
+    fooCreateInput.values =
+        ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput fooUpdateInput = new LabelDefinitionInput();
+    fooUpdateInput.function = LabelFunction.ANY_WITH_BLOCK.getFunctionName();
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo");
+    input.create = ImmutableList.of(fooCreateInput);
+    input.update = ImmutableMap.of("Foo", fooUpdateInput);
+
+    gApi.projects().name(project.get()).labels(input);
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("Foo").get();
+    assertThat(fooLabel.function).isEqualTo(fooUpdateInput.function);
+  }
+
+  @Test
+  public void cannotDeleteAndUpdateLabel() throws Exception {
+    configLabel("Foo", LabelFunction.NO_OP);
+
+    LabelDefinitionInput fooInput = new LabelDefinitionInput();
+    fooInput.function = LabelFunction.MAX_NO_BLOCK.getFunctionName();
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Foo");
+    input.update = ImmutableMap.of("Foo", fooInput);
+
+    UnprocessableEntityException thrown =
+        assertThrows(
+            UnprocessableEntityException.class,
+            () -> gApi.projects().name(project.get()).labels(input));
+    assertThat(thrown).hasMessageThat().contains("label Foo not found");
+  }
+
+  @Test
+  public void createAndUpdateLabel() throws Exception {
+    LabelDefinitionInput fooCreateInput = new LabelDefinitionInput();
+    fooCreateInput.name = "Foo";
+    fooCreateInput.function = LabelFunction.MAX_NO_BLOCK.getFunctionName();
+    fooCreateInput.values =
+        ImmutableMap.of("+1", "Looks Good", " 0", "Don't Know", "-1", "Looks Bad");
+
+    LabelDefinitionInput fooUpdateInput = new LabelDefinitionInput();
+    fooUpdateInput.function = LabelFunction.ANY_WITH_BLOCK.getFunctionName();
+
+    BatchLabelInput input = new BatchLabelInput();
+    input.create = ImmutableList.of(fooCreateInput);
+    input.update = ImmutableMap.of("Foo", fooUpdateInput);
+
+    gApi.projects().name(project.get()).labels(input);
+
+    LabelDefinitionInfo fooLabel = gApi.projects().name(project.get()).label("Foo").get();
+    assertThat(fooLabel.function).isEqualTo(fooUpdateInput.function);
+  }
+
+  @Test
+  public void noOpUpdate() throws Exception {
+    RevCommit refsMetaConfigHead =
+        projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG);
+
+    gApi.projects().name(allProjects.get()).labels(new BatchLabelInput());
+
+    assertThat(projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG))
+        .isEqualTo(refsMetaConfigHead);
+  }
+
+  @Test
+  public void defaultCommitMessage() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.delete = ImmutableList.of("Code-Review");
+    gApi.projects().name(allProjects.get()).labels(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Update labels");
+  }
+
+  @Test
+  public void withCommitMessage() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.commitMessage = "Batch Update Labels";
+    input.delete = ImmutableList.of("Code-Review");
+    gApi.projects().name(allProjects.get()).labels(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo(input.commitMessage);
+  }
+
+  @Test
+  public void commitMessageIsTrimmed() throws Exception {
+    BatchLabelInput input = new BatchLabelInput();
+    input.commitMessage = " Batch Update Labels ";
+    input.delete = ImmutableList.of("Code-Review");
+    gApi.projects().name(allProjects.get()).labels(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Batch Update Labels");
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java
new file mode 100644
index 0000000..97b795f
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java
@@ -0,0 +1,895 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.acceptance.rest.project;
+
+import static com.google.common.truth.Truth.assertThat;
+import static com.google.gerrit.acceptance.testsuite.project.TestProjectUpdate.allow;
+import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
+import static com.google.gerrit.testing.GerritJUnit.assertThrows;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
+import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
+import com.google.gerrit.common.data.LabelFunction;
+import com.google.gerrit.common.data.LabelType;
+import com.google.gerrit.common.data.Permission;
+import com.google.gerrit.entities.RefNames;
+import com.google.gerrit.extensions.common.LabelDefinitionInfo;
+import com.google.gerrit.extensions.common.LabelDefinitionInput;
+import com.google.gerrit.extensions.restapi.AuthException;
+import com.google.gerrit.extensions.restapi.BadRequestException;
+import com.google.gerrit.extensions.restapi.ResourceConflictException;
+import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
+import com.google.inject.Inject;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.junit.Test;
+
+@NoHttpd
+public class SetLabelIT extends AbstractDaemonTest {
+  @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject private ProjectOperations projectOperations;
+
+  @Test
+  public void anonymous() throws Exception {
+    requestScopeOperations.setApiUserAnonymous();
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () ->
+                gApi.projects()
+                    .name(allProjects.get())
+                    .label("Code-Review")
+                    .update(new LabelDefinitionInput()));
+    assertThat(thrown).hasMessageThat().contains("Authentication required");
+  }
+
+  @Test
+  public void notAllowed() throws Exception {
+    projectOperations
+        .project(allProjects)
+        .forUpdate()
+        .add(allow(Permission.READ).ref(RefNames.REFS_CONFIG).group(REGISTERED_USERS))
+        .update();
+
+    requestScopeOperations.setApiUser(user.id());
+    AuthException thrown =
+        assertThrows(
+            AuthException.class,
+            () ->
+                gApi.projects()
+                    .name(allProjects.get())
+                    .label("Code-Review")
+                    .update(new LabelDefinitionInput()));
+    assertThat(thrown).hasMessageThat().contains("write refs/meta/config not permitted");
+  }
+
+  @Test
+  public void updateName() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "Foo-Review";
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.name).isEqualTo(input.name);
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Foo-Review").get()).isNotNull();
+    assertThrows(
+        ResourceNotFoundException.class,
+        () -> gApi.projects().name(allProjects.get()).label("Code-Review").get());
+  }
+
+  @Test
+  public void nameIsTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = " Foo-Review ";
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.name).isEqualTo("Foo-Review");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Foo-Review").get()).isNotNull();
+    assertThrows(
+        ResourceNotFoundException.class,
+        () -> gApi.projects().name(allProjects.get()).label("Code-Review").get());
+  }
+
+  @Test
+  public void cannotSetEmptyName() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("name cannot be empty");
+  }
+
+  @Test
+  public void cannotSetInvalidName() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "INVALID_NAME";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("invalid name: " + input.name);
+  }
+
+  @Test
+  public void cannotSetNameIfNameClashes() throws Exception {
+    configLabel("Foo-Review", LabelFunction.NO_OP);
+    configLabel("Bar-Review", LabelFunction.NO_OP);
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "Bar-Review";
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(project.get()).label("Foo-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("name " + input.name + " already in use");
+  }
+
+  @Test
+  public void cannotSetNameIfNameConflicts() throws Exception {
+    configLabel("Foo-Review", LabelFunction.NO_OP);
+    configLabel("Bar-Review", LabelFunction.NO_OP);
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.name = "bar-review";
+
+    ResourceConflictException thrown =
+        assertThrows(
+            ResourceConflictException.class,
+            () -> gApi.projects().name(project.get()).label("Foo-Review").update(input));
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("name bar-review conflicts with existing label Bar-Review");
+  }
+
+  @Test
+  public void updateFunction() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = LabelFunction.NO_OP.getFunctionName();
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.function).isEqualTo(input.function);
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().function)
+        .isEqualTo(input.function);
+  }
+
+  @Test
+  public void functionIsTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = " " + LabelFunction.NO_OP.getFunctionName() + " ";
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.function).isEqualTo(LabelFunction.NO_OP.getFunctionName());
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().function)
+        .isEqualTo(LabelFunction.NO_OP.getFunctionName());
+  }
+
+  @Test
+  public void cannotSetEmptyFunction() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = "";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("function cannot be empty");
+  }
+
+  @Test
+  public void cannotSetUnknownFunction() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = "UnknownFunction";
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("unknown function: " + input.function);
+  }
+
+  @Test
+  public void cannotSetEmptyValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of();
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("values cannot be empty");
+  }
+
+  @Test
+  public void updateValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Positive values can be specified as '<value>' or '+<value>'.
+    input.values =
+        ImmutableMap.of(
+            "2",
+            "Looks Very Good",
+            "+1",
+            "Looks Good",
+            "0",
+            "Don't Know",
+            "-1",
+            "Looks Bad",
+            "-2",
+            "Looks Very Bad");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.values)
+        .containsExactly(
+            "+2", "Looks Very Good",
+            "+1", "Looks Good",
+            " 0", "Don't Know",
+            "-1", "Looks Bad",
+            "-2", "Looks Very Bad");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().values)
+        .containsExactly(
+            "+2", "Looks Very Good",
+            "+1", "Looks Good",
+            " 0", "Don't Know",
+            "-1", "Looks Bad",
+            "-2", "Looks Very Bad");
+  }
+
+  @Test
+  public void valuesAndDescriptionsAreTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Positive values can be specified as '<value>' or '+<value>'.
+    input.values =
+        ImmutableMap.of(
+            " 2 ",
+            " Looks Very Good ",
+            " +1 ",
+            " Looks Good ",
+            " 0 ",
+            " Don't Know ",
+            " -1 ",
+            " Looks Bad ",
+            " -2 ",
+            " Looks Very Bad ");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.values)
+        .containsExactly(
+            "+2", "Looks Very Good",
+            "+1", "Looks Good",
+            " 0", "Don't Know",
+            "-1", "Looks Bad",
+            "-2", "Looks Very Bad");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().values)
+        .containsExactly(
+            "+2", "Looks Very Good",
+            "+1", "Looks Good",
+            " 0", "Don't Know",
+            "-1", "Looks Bad",
+            "-2", "Looks Very Bad");
+  }
+
+  @Test
+  public void cannotSetInvalidValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("invalidValue", "description");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("invalid value: invalidValue");
+  }
+
+  @Test
+  public void cannotSetValueWithEmptyDescription() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.values = ImmutableMap.of("+1", "");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("description for value '+1' cannot be empty");
+  }
+
+  @Test
+  public void cannotSetDuplicateValues() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Positive values can be specified as '<value>' or '+<value>'.
+    input.values =
+        ImmutableMap.of(
+            "+1", "Looks Good", "1", "Looks Good", "0", "Don't Know", "-1", "Looks Bad");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("duplicate value: 1");
+  }
+
+  @Test
+  public void updateDefaultValue() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.defaultValue = 1;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.defaultValue).isEqualTo(input.defaultValue);
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().defaultValue)
+        .isEqualTo(input.defaultValue);
+  }
+
+  @Test
+  public void cannotSetInvalidDefaultValue() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.defaultValue = 5;
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("invalid default value: " + input.defaultValue);
+  }
+
+  @Test
+  public void updateBranches() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    // Branches can be full ref, ref pattern or regular expression.
+    input.branches =
+        ImmutableList.of("refs/heads/master", "refs/heads/foo/*", "^refs/heads/stable-.*");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.branches).containsExactlyElementsIn(input.branches);
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .containsExactlyElementsIn(input.branches);
+  }
+
+  @Test
+  public void branchesAreTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.branches =
+        ImmutableList.of(" refs/heads/master ", " refs/heads/foo/* ", " ^refs/heads/stable-.* ");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.branches)
+        .containsExactly("refs/heads/master", "refs/heads/foo/*", "^refs/heads/stable-.*");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .containsExactly("refs/heads/master", "refs/heads/foo/*", "^refs/heads/stable-.*");
+  }
+
+  @Test
+  public void emptyBranchesAreIgnored() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.branches = ImmutableList.of("refs/heads/master", "", " ");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.branches).containsExactly("refs/heads/master");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .containsExactly("refs/heads/master");
+  }
+
+  @Test
+  public void branchesCanBeUnset() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.branches = ImmutableList.of("refs/heads/master");
+    gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .isNotNull();
+
+    input.branches = ImmutableList.of();
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.branches).isNull();
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .isNull();
+  }
+
+  @Test
+  public void cannotSetInvalidBranch() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.branches = ImmutableList.of("refs heads master");
+
+    BadRequestException thrown =
+        assertThrows(
+            BadRequestException.class,
+            () -> gApi.projects().name(allProjects.get()).label("Code-Review").update(input));
+    assertThat(thrown).hasMessageThat().contains("invalid branch: refs heads master");
+  }
+
+  @Test
+  public void branchesAreAutomaticallyPrefixedWithRefsHeads() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.branches = ImmutableList.of("master", "refs/meta/config");
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(updatedLabel.branches).containsExactly("refs/heads/master", "refs/meta/config");
+
+    assertThat(gApi.projects().name(allProjects.get()).label("Code-Review").get().branches)
+        .containsExactly("refs/heads/master", "refs/meta/config");
+  }
+
+  @Test
+  public void setCanOverride() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCanOverride(false);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().canOverride).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.canOverride = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.canOverride).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().canOverride).isTrue();
+  }
+
+  @Test
+  public void unsetCanOverride() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().canOverride).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.canOverride = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.canOverride).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().canOverride).isNull();
+  }
+
+  @Test
+  public void setCopyAnyScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAnyScore).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAnyScore = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAnyScore).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAnyScore).isTrue();
+  }
+
+  @Test
+  public void unsetCopyAnyScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAnyScore(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAnyScore).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAnyScore = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAnyScore).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAnyScore).isNull();
+  }
+
+  @Test
+  public void setCopyMinScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMinScore).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyMinScore = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyMinScore).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMinScore).isTrue();
+  }
+
+  @Test
+  public void unsetCopyMinScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyMinScore(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMinScore).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyMinScore = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyMinScore).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMinScore).isNull();
+  }
+
+  @Test
+  public void setCopyMaxScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMaxScore).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyMaxScore = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyMaxScore).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMaxScore).isTrue();
+  }
+
+  @Test
+  public void unsetCopyMaxScore() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyMaxScore(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMaxScore).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyMaxScore = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyMaxScore).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyMaxScore).isNull();
+  }
+
+  @Test
+  public void setCopyAllScoresIfNoChange() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAllScoresIfNoChange(false);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoChange)
+        .isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresIfNoChange = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresIfNoChange).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoChange)
+        .isTrue();
+  }
+
+  @Test
+  public void unsetCopyAllScoresIfNoChange() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoChange)
+        .isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresIfNoChange = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresIfNoChange).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoChange)
+        .isNull();
+  }
+
+  @Test
+  public void setCopyAllScoresIfNoCodeChange() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoCodeChange)
+        .isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresIfNoCodeChange = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresIfNoCodeChange).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoCodeChange)
+        .isTrue();
+  }
+
+  @Test
+  public void unsetCopyAllScoresIfNoCodeChange() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAllScoresIfNoCodeChange(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoCodeChange)
+        .isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresIfNoCodeChange = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresIfNoCodeChange).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoCodeChange)
+        .isNull();
+  }
+
+  @Test
+  public void setCopyAllScoresOnTrivialRebase() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresOnTrivialRebase)
+        .isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresOnTrivialRebase = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresOnTrivialRebase).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresOnTrivialRebase)
+        .isTrue();
+  }
+
+  @Test
+  public void unsetCopyAllScoresOnTrivialRebase() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAllScoresOnTrivialRebase(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresOnTrivialRebase)
+        .isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresOnTrivialRebase = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresOnTrivialRebase).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresOnTrivialRebase)
+        .isNull();
+  }
+
+  @Test
+  public void setCopyAllScoresOnMergeFirstParentUpdate() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(
+            gApi.projects()
+                .name(project.get())
+                .label("foo")
+                .get()
+                .copyAllScoresOnMergeFirstParentUpdate)
+        .isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresOnMergeFirstParentUpdate = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresOnMergeFirstParentUpdate).isTrue();
+
+    assertThat(
+            gApi.projects()
+                .name(project.get())
+                .label("foo")
+                .get()
+                .copyAllScoresOnMergeFirstParentUpdate)
+        .isTrue();
+  }
+
+  @Test
+  public void unsetCopyAllScoresOnMergeFirstParentUpdate() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(
+            gApi.projects()
+                .name(project.get())
+                .label("foo")
+                .get()
+                .copyAllScoresOnMergeFirstParentUpdate)
+        .isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.copyAllScoresOnMergeFirstParentUpdate = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.copyAllScoresOnMergeFirstParentUpdate).isNull();
+
+    assertThat(
+            gApi.projects()
+                .name(project.get())
+                .label("foo")
+                .get()
+                .copyAllScoresOnMergeFirstParentUpdate)
+        .isNull();
+  }
+
+  @Test
+  public void setAllowPostSubmit() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setAllowPostSubmit(false);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().allowPostSubmit).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.allowPostSubmit = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.allowPostSubmit).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().allowPostSubmit).isTrue();
+  }
+
+  @Test
+  public void unsetAllowPostSubmit() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().allowPostSubmit).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.allowPostSubmit = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.allowPostSubmit).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().allowPostSubmit).isNull();
+  }
+
+  @Test
+  public void setIgnoreSelfApproval() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    assertThat(gApi.projects().name(project.get()).label("foo").get().ignoreSelfApproval).isNull();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.ignoreSelfApproval = true;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.ignoreSelfApproval).isTrue();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().ignoreSelfApproval).isTrue();
+  }
+
+  @Test
+  public void unsetIgnoreSelfApproval() throws Exception {
+    configLabel("foo", LabelFunction.NO_OP);
+    try (ProjectConfigUpdate u = updateProject(project)) {
+      LabelType labelType = u.getConfig().getLabelSections().get("foo");
+      labelType.setIgnoreSelfApproval(true);
+      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.save();
+    }
+    assertThat(gApi.projects().name(project.get()).label("foo").get().ignoreSelfApproval).isTrue();
+
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.ignoreSelfApproval = false;
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects().name(project.get()).label("foo").update(input);
+    assertThat(updatedLabel.ignoreSelfApproval).isNull();
+
+    assertThat(gApi.projects().name(project.get()).label("foo").get().ignoreSelfApproval).isNull();
+  }
+
+  @Test
+  public void noOpUpdate() throws Exception {
+    RevCommit refsMetaConfigHead =
+        projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG);
+
+    LabelDefinitionInfo updatedLabel =
+        gApi.projects()
+            .name(allProjects.get())
+            .label("Code-Review")
+            .update(new LabelDefinitionInput());
+    LabelAssert.assertCodeReviewLabel(updatedLabel);
+
+    LabelAssert.assertCodeReviewLabel(
+        gApi.projects().name(allProjects.get()).label("Code-Review").get());
+
+    assertThat(projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG))
+        .isEqualTo(refsMetaConfigHead);
+  }
+
+  @Test
+  public void defaultCommitMessage() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = LabelFunction.NO_OP.getFunctionName();
+    gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Update label");
+  }
+
+  @Test
+  public void withCommitMessage() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = LabelFunction.NO_OP.getFunctionName();
+    input.commitMessage = "Set NoOp function";
+    gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo(input.commitMessage);
+  }
+
+  @Test
+  public void commitMessageIsTrimmed() throws Exception {
+    LabelDefinitionInput input = new LabelDefinitionInput();
+    input.function = LabelFunction.NO_OP.getFunctionName();
+    input.commitMessage = " Set NoOp function ";
+    gApi.projects().name(allProjects.get()).label("Code-Review").update(input);
+    assertThat(
+            projectOperations.project(allProjects).getHead(RefNames.REFS_CONFIG).getShortMessage())
+        .isEqualTo("Set NoOp function");
+  }
+}
diff --git a/javatests/com/google/gerrit/acceptance/rest/revision/RevisionIT.java b/javatests/com/google/gerrit/acceptance/rest/revision/RevisionIT.java
index 220254b..df6a264 100644
--- a/javatests/com/google/gerrit/acceptance/rest/revision/RevisionIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/revision/RevisionIT.java
@@ -19,13 +19,13 @@
 import static com.google.gerrit.acceptance.PushOneCommit.FILE_NAME;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
+import com.google.common.io.BaseEncoding;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.RestResponse;
 import com.google.gerrit.extensions.api.changes.ReviewInput;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.util.Base64;
 import org.junit.Test;
 
 public class RevisionIT extends AbstractDaemonTest {
@@ -50,7 +50,7 @@
                 + FILE_NAME
                 + "/content?parent=1");
     response.assertOK();
-    assertThat(new String(Base64.decode(response.getEntityContent()), UTF_8))
+    assertThat(new String(BaseEncoding.base64().decode(response.getEntityContent()), UTF_8))
         .isEqualTo(parentContent);
   }
 
diff --git a/javatests/com/google/gerrit/acceptance/server/change/BUILD b/javatests/com/google/gerrit/acceptance/server/change/BUILD
index 4d1634d..500ab06 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/BUILD
+++ b/javatests/com/google/gerrit/acceptance/server/change/BUILD
@@ -4,5 +4,8 @@
     srcs = glob(["*IT.java"]),
     group = "server_change",
     labels = ["server"],
-    deps = ["//java/com/google/gerrit/server/util/time"],
+    deps = [
+        "//java/com/google/gerrit/server/logging",
+        "//java/com/google/gerrit/server/util/time",
+    ],
 )
diff --git a/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java b/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
index b1194b1..ba41d7e 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/change/CommentsIT.java
@@ -29,6 +29,7 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
+import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.Patch;
@@ -83,6 +84,7 @@
   @Inject private Provider<ChangesCollection> changes;
   @Inject private Provider<PostReview> postReview;
   @Inject private RequestScopeOperations requestScopeOperations;
+  @Inject ProjectOperations projectOperations;
 
   private final Integer[] lines = {0, 1};
 
@@ -485,7 +487,7 @@
       ChangeResource changeRsrc =
           changes.get().parse(TopLevelResource.INSTANCE, IdString.fromDecoded(changeId));
       RevisionResource revRsrc = revisions.parse(changeRsrc, IdString.fromDecoded(revId));
-      postReview.get().apply(batchUpdateFactory, revRsrc, input, timestamp);
+      postReview.get().apply(revRsrc, input, timestamp);
       Map<String, List<CommentInfo>> result = getPublishedComments(changeId, revId);
       assertThat(result).isNotEmpty();
       CommentInfo actual = Iterables.getOnlyElement(result.get(comment.path));
diff --git a/javatests/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java b/javatests/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java
index 1e2d1ba..08719d3 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/change/ConsistencyCheckerIT.java
@@ -39,6 +39,7 @@
 import com.google.gerrit.server.change.ConsistencyChecker;
 import com.google.gerrit.server.change.NotifyResolver;
 import com.google.gerrit.server.change.PatchSetInserter;
+import com.google.gerrit.server.logging.RequestId;
 import com.google.gerrit.server.notedb.ChangeNoteUtil;
 import com.google.gerrit.server.notedb.ChangeNotes;
 import com.google.gerrit.server.notedb.Sequences;
@@ -313,7 +314,8 @@
             @Override
             public boolean updateChange(ChangeContext ctx) {
               ctx.getChange().setStatus(Change.Status.MERGED);
-              ctx.getUpdate(ctx.getChange().currentPatchSetId()).fixStatus(Change.Status.MERGED);
+              ctx.getUpdate(ctx.getChange().currentPatchSetId())
+                  .fixStatusToMerged(new RequestId(ctx.getChange().getId().toString()));
               return true;
             }
           });
@@ -862,7 +864,8 @@
             @Override
             public boolean updateChange(ChangeContext ctx) {
               ctx.getChange().setStatus(Change.Status.MERGED);
-              ctx.getUpdate(ctx.getChange().currentPatchSetId()).fixStatus(Change.Status.MERGED);
+              ctx.getUpdate(ctx.getChange().currentPatchSetId())
+                  .fixStatusToMerged(new RequestId(ctx.getChange().getId().toString()));
               return true;
             }
           });
diff --git a/javatests/com/google/gerrit/acceptance/server/change/GetRelatedIT.java b/javatests/com/google/gerrit/acceptance/server/change/GetRelatedIT.java
index e369d1b..b544f6e 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/GetRelatedIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/change/GetRelatedIT.java
@@ -25,11 +25,11 @@
 import com.google.common.collect.Iterables;
 import com.google.common.truth.Correspondence;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.UseClockStep;
 import com.google.gerrit.acceptance.UseTimezone;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.account.AccountOperations;
 import com.google.gerrit.acceptance.testsuite.group.GroupOperations;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
diff --git a/javatests/com/google/gerrit/acceptance/server/change/PatchListCacheIT.java b/javatests/com/google/gerrit/acceptance/server/change/PatchListCacheIT.java
index 7c78d61..b23f9a3 100644
--- a/javatests/com/google/gerrit/acceptance/server/change/PatchListCacheIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/change/PatchListCacheIT.java
@@ -39,7 +39,9 @@
 import com.google.gerrit.server.patch.Text;
 import com.google.inject.Inject;
 import com.google.inject.name.Named;
+import java.lang.reflect.Field;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Optional;
@@ -66,6 +68,25 @@
   private Cache<PatchListKey, PatchList> abstractPatchListCache;
 
   @Test
+  public void ensureLegacyBackendIsUsedForFileCacheBackend() throws Exception {
+    Field fileCacheField = patchListCache.getClass().getDeclaredField("fileCache");
+    fileCacheField.setAccessible(true);
+    // Use the reflection to access "localCache" field that is only present in Guava backend.
+    assertThat(
+            Arrays.stream(fileCacheField.get(patchListCache).getClass().getDeclaredFields())
+                .anyMatch(f -> f.getName().equals("localCache")))
+        .isTrue();
+
+    // intraCache (and all other cache backends) should use Caffeine backend.
+    Field intraCacheField = patchListCache.getClass().getDeclaredField("intraCache");
+    intraCacheField.setAccessible(true);
+    assertThat(
+            Arrays.stream(intraCacheField.get(patchListCache).getClass().getDeclaredFields())
+                .noneMatch(f -> f.getName().equals("localCache")))
+        .isTrue();
+  }
+
+  @Test
   public void listPatchesAgainstBase() throws Exception {
     commitBuilder().add(FILE_D, "4").message(SUBJECT_1).create();
     pushHead(testRepo, "refs/heads/master", false);
diff --git a/javatests/com/google/gerrit/acceptance/server/event/EventPayloadIT.java b/javatests/com/google/gerrit/acceptance/server/event/EventPayloadIT.java
index 8744cfad..d973934 100644
--- a/javatests/com/google/gerrit/acceptance/server/event/EventPayloadIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/event/EventPayloadIT.java
@@ -19,8 +19,8 @@
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.extensions.events.RevisionCreatedListener;
 import com.google.inject.Inject;
 import org.junit.Test;
diff --git a/javatests/com/google/gerrit/acceptance/server/mail/EmailValidatorIT.java b/javatests/com/google/gerrit/acceptance/server/mail/EmailValidatorIT.java
index d0b7f15d..cc61dfb 100644
--- a/javatests/com/google/gerrit/acceptance/server/mail/EmailValidatorIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/mail/EmailValidatorIT.java
@@ -19,7 +19,7 @@
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.server.mail.send.OutgoingEmailValidator;
 import com.google.inject.Inject;
 import java.io.BufferedReader;
diff --git a/javatests/com/google/gerrit/acceptance/server/mail/ListMailFilterIT.java b/javatests/com/google/gerrit/acceptance/server/mail/ListMailFilterIT.java
index 13f0416..e03f6fe 100644
--- a/javatests/com/google/gerrit/acceptance/server/mail/ListMailFilterIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/mail/ListMailFilterIT.java
@@ -16,8 +16,8 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.extensions.common.ChangeMessageInfo;
 import com.google.gerrit.extensions.common.CommentInfo;
diff --git a/javatests/com/google/gerrit/acceptance/server/mail/MailSenderIT.java b/javatests/com/google/gerrit/acceptance/server/mail/MailSenderIT.java
index c395c81..0ae9ad2 100644
--- a/javatests/com/google/gerrit/acceptance/server/mail/MailSenderIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/mail/MailSenderIT.java
@@ -16,7 +16,7 @@
 
 import static com.google.common.truth.Truth.assertThat;
 
-import com.google.gerrit.acceptance.GerritConfig;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.mail.EmailHeader;
 import java.net.URI;
 import java.util.Map;
diff --git a/javatests/com/google/gerrit/acceptance/ssh/AbstractIndexTests.java b/javatests/com/google/gerrit/acceptance/ssh/AbstractIndexTests.java
index 4fe0df4..f866fff 100644
--- a/javatests/com/google/gerrit/acceptance/ssh/AbstractIndexTests.java
+++ b/javatests/com/google/gerrit/acceptance/ssh/AbstractIndexTests.java
@@ -22,10 +22,10 @@
 import com.google.gerrit.acceptance.ChangeIndexedCounter;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.inject.Inject;
diff --git a/javatests/com/google/gerrit/acceptance/ssh/SshCommandsIT.java b/javatests/com/google/gerrit/acceptance/ssh/SshCommandsIT.java
index 4e9c4a4..9b8b19c 100644
--- a/javatests/com/google/gerrit/acceptance/ssh/SshCommandsIT.java
+++ b/javatests/com/google/gerrit/acceptance/ssh/SshCommandsIT.java
@@ -67,6 +67,7 @@
           "receive-pack",
           "rename-group",
           "review",
+          "sequence",
           "set-account",
           "set-head",
           "set-members",
@@ -96,6 +97,7 @@
               "gerrit plugin",
               ImmutableList.of("add", "enable", "install", "ls", "reload", "remove", "rm"))
           .put("gerrit test-submit", ImmutableList.of("rule", "type"))
+          .put("gerrit sequence", ImmutableList.of("set", "show"))
           .build();
 
   private static final ImmutableMap<String, List<String>> SLAVE_COMMANDS =
diff --git a/javatests/com/google/gerrit/acceptance/ssh/UploadArchiveIT.java b/javatests/com/google/gerrit/acceptance/ssh/UploadArchiveIT.java
index 34406e0..f1db016 100644
--- a/javatests/com/google/gerrit/acceptance/ssh/UploadArchiveIT.java
+++ b/javatests/com/google/gerrit/acceptance/ssh/UploadArchiveIT.java
@@ -19,11 +19,11 @@
 
 import com.google.common.base.Splitter;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
-import com.google.gerrit.acceptance.GerritConfig;
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.PushOneCommit;
 import com.google.gerrit.acceptance.PushOneCommit.Result;
 import com.google.gerrit.acceptance.UseSsh;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.git.ObjectIds;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
diff --git a/javatests/com/google/gerrit/index/query/RangeUtilTest.java b/javatests/com/google/gerrit/index/query/RangeUtilTest.java
new file mode 100644
index 0000000..681f9d99b
--- /dev/null
+++ b/javatests/com/google/gerrit/index/query/RangeUtilTest.java
@@ -0,0 +1,34 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.index.query;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gerrit.index.query.RangeUtil.Range;
+import org.junit.Test;
+
+public class RangeUtilTest {
+  @Test
+  public void getRangeForValueOutsideOfMinMaxRange_minNotGreaterThanMax() {
+    for (String operator : ImmutableList.of("=", ">", ">=", "<", "<=")) {
+      Range range = RangeUtil.getRange("foo", operator, 10, -4, 4);
+      assertThat(range.min).isAtMost(range.max);
+
+      range = RangeUtil.getRange("foo", operator, -10, -4, 4);
+      assertThat(range.min).isAtMost(range.max);
+    }
+  }
+}
diff --git a/javatests/com/google/gerrit/mail/BUILD b/javatests/com/google/gerrit/mail/BUILD
index bd2c478..3d63844 100644
--- a/javatests/com/google/gerrit/mail/BUILD
+++ b/javatests/com/google/gerrit/mail/BUILD
@@ -15,7 +15,6 @@
         "//lib:guava-retrying",
         "//lib:jgit",
         "//lib:jgit-junit",
-        "//lib/commons:codec",
         "//lib/guice",
         "//lib/truth",
         "//lib/truth:truth-java8-extension",
diff --git a/javatests/com/google/gerrit/server/BUILD b/javatests/com/google/gerrit/server/BUILD
index b94a709..59ed018 100644
--- a/javatests/com/google/gerrit/server/BUILD
+++ b/javatests/com/google/gerrit/server/BUILD
@@ -55,6 +55,7 @@
         "//java/com/google/gerrit/server/account/externalids/testing",
         "//java/com/google/gerrit/server/cache/serialize",
         "//java/com/google/gerrit/server/cache/testing",
+        "//java/com/google/gerrit/server/git/receive:ref_cache",
         "//java/com/google/gerrit/server/ioutil",
         "//java/com/google/gerrit/server/logging",
         "//java/com/google/gerrit/server/project/testing:project-test-util",
@@ -73,7 +74,6 @@
         "//lib:protobuf",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:codec",
         "//lib/flogger:api",
         "//lib/guice",
         "//lib/mockito",
diff --git a/javatests/com/google/gerrit/server/account/externalids/ExternalIDCacheLoaderTest.java b/javatests/com/google/gerrit/server/account/externalids/ExternalIDCacheLoaderTest.java
index 054b1aa..2f64ed0 100644
--- a/javatests/com/google/gerrit/server/account/externalids/ExternalIDCacheLoaderTest.java
+++ b/javatests/com/google/gerrit/server/account/externalids/ExternalIDCacheLoaderTest.java
@@ -18,9 +18,9 @@
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyZeroInteractions;
-import static org.mockito.Mockito.when;
 
 import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.entities.Account;
 import com.google.gerrit.entities.RefNames;
@@ -44,7 +44,6 @@
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Mock;
 import org.mockito.Mockito;
 import org.mockito.junit.MockitoJUnitRunner;
 
@@ -52,8 +51,7 @@
 public class ExternalIDCacheLoaderTest {
   private static AllUsersName ALL_USERS = new AllUsersName(AllUsersNameProvider.DEFAULT);
 
-  @Mock Cache<ObjectId, AllExternalIds> externalIdCache;
-
+  private Cache<ObjectId, AllExternalIds> externalIdCache;
   private ExternalIdCacheLoader loader;
   private GitRepositoryManager repoManager = new InMemoryRepositoryManager();
   private ExternalIdReader externalIdReader;
@@ -61,6 +59,7 @@
 
   @Before
   public void setUp() throws Exception {
+    externalIdCache = CacheBuilder.newBuilder().build();
     repoManager.createRepository(ALL_USERS).close();
     externalIdReader = new ExternalIdReader(repoManager, ALL_USERS, new DisabledMetricMaker());
     externalIdReaderSpy = Mockito.spy(externalIdReader);
@@ -78,8 +77,7 @@
   public void reloadsSingleUpdateUsingPartialReload() throws Exception {
     ObjectId firstState = insertExternalId(1, 1);
     ObjectId head = insertExternalId(2, 2);
-
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(allFromGit(firstState));
+    externalIdCache.put(firstState, allFromGit(firstState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -91,8 +89,7 @@
     insertExternalId(2, 2);
     insertExternalId(3, 3);
     ObjectId head = insertExternalId(4, 4);
-
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(allFromGit(firstState));
+    externalIdCache.put(firstState, allFromGit(firstState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -100,11 +97,9 @@
 
   @Test
   public void reloadsAllExternalIdsWhenNoOldStateIsCached() throws Exception {
-    ObjectId firstState = insertExternalId(1, 1);
+    insertExternalId(1, 1);
     ObjectId head = insertExternalId(2, 2);
 
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(null);
-
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verify(externalIdReaderSpy, times(1)).all(head);
   }
@@ -144,8 +139,7 @@
     ObjectId firstState = insertExternalId(1, 1);
     ObjectId head = deleteExternalId(1, 1);
     assertThat(allFromGit(head).byAccount().size()).isEqualTo(0);
-
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(allFromGit(firstState));
+    externalIdCache.put(firstState, allFromGit(firstState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -159,8 +153,7 @@
             externalId(1, 1),
             ExternalId.create("fooschema", "bar1", Account.id(1), "foo@bar.com", "password"));
     assertThat(allFromGit(head).byAccount().size()).isEqualTo(1);
-
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(allFromGit(firstState));
+    externalIdCache.put(firstState, allFromGit(firstState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -177,7 +170,7 @@
       head = repo.exactRef(RefNames.REFS_EXTERNAL_IDS).getObjectId();
     }
 
-    when(externalIdCache.getIfPresent(firstState)).thenReturn(allFromGit(firstState));
+    externalIdCache.put(firstState, allFromGit(firstState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -190,8 +183,7 @@
     ObjectId oldState = inserExternalIds(257);
     assertAllFilesHaveSlashesInPath();
     ObjectId head = insertExternalId(500, 500);
-
-    when(externalIdCache.getIfPresent(oldState)).thenReturn(allFromGit(oldState));
+    externalIdCache.put(oldState, allFromGit(oldState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
@@ -205,8 +197,7 @@
     // Create one more external ID and then have the Loader compute the new state
     ObjectId head = insertExternalId(500, 500);
     assertAllFilesHaveSlashesInPath(); // NoteMap resharded
-
-    when(externalIdCache.getIfPresent(oldState)).thenReturn(allFromGit(oldState));
+    externalIdCache.put(oldState, allFromGit(oldState));
 
     assertThat(loader.load(head)).isEqualTo(allFromGit(head));
     verifyZeroInteractions(externalIdReaderSpy);
diff --git a/javatests/com/google/gerrit/server/git/GroupCollectorTest.java b/javatests/com/google/gerrit/server/git/GroupCollectorTest.java
index 6175385..63f83b0 100644
--- a/javatests/com/google/gerrit/server/git/GroupCollectorTest.java
+++ b/javatests/com/google/gerrit/server/git/GroupCollectorTest.java
@@ -21,10 +21,13 @@
 import com.google.common.collect.SortedSetMultimap;
 import com.google.gerrit.entities.Change;
 import com.google.gerrit.entities.PatchSet;
+import com.google.gerrit.server.git.receive.ReceivePackRefCache;
+import java.io.IOException;
 import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
 import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.RefUpdate;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevSort;
 import org.eclipse.jgit.revwalk.RevWalk;
@@ -44,8 +47,7 @@
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(a, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(a, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
   }
@@ -56,8 +58,7 @@
     RevCommit a = tr.commit().parent(branchTip).create();
     RevCommit b = tr.commit().parent(a).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(b, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(b, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(b, a.name());
@@ -67,12 +68,12 @@
   public void commitWhoseParentIsExistingPatchSetGetsParentsGroup() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit b = tr.commit().parent(a).create();
 
     String group = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
     SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(
-            newWalk(b, branchTip), patchSets().put(a, psId(1, 1)), groups().put(psId(1, 1), group));
+        collectGroups(newWalk(b, branchTip), groups().put(psId(1, 1), group));
 
     assertThat(groups).containsEntry(a, group);
     assertThat(groups).containsEntry(b, group);
@@ -84,8 +85,7 @@
     RevCommit a = tr.commit().parent(branchTip).create();
     RevCommit b = tr.commit().parent(a).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(b, branchTip), patchSets().put(a, psId(1, 1)), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(b, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(b, a.name());
@@ -98,8 +98,7 @@
     RevCommit b = tr.commit().parent(branchTip).create();
     RevCommit m = tr.commit().parent(a).parent(b).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(m, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(m, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(b, a.name());
@@ -110,13 +109,13 @@
   public void mergeCommitWhereOneParentHasExistingGroup() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit b = tr.commit().parent(branchTip).create();
     RevCommit m = tr.commit().parent(a).parent(b).create();
 
     String group = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
     SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(
-            newWalk(m, branchTip), patchSets().put(b, psId(1, 1)), groups().put(psId(1, 1), group));
+        collectGroups(newWalk(m, branchTip), groups().put(psId(1, 1), group));
 
     // Merge commit and other parent get the existing group.
     assertThat(groups).containsEntry(a, group);
@@ -128,16 +127,16 @@
   public void mergeCommitWhereBothParentsHaveDifferentGroups() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit b = tr.commit().parent(branchTip).create();
+    createRef(psId(2, 1), b, tr);
     RevCommit m = tr.commit().parent(a).parent(b).create();
 
     String group1 = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
     String group2 = "1234567812345678123456781234567812345678";
     SortedSetMultimap<ObjectId, String> groups =
         collectGroups(
-            newWalk(m, branchTip),
-            patchSets().put(a, psId(1, 1)).put(b, psId(2, 1)),
-            groups().put(psId(1, 1), group1).put(psId(2, 1), group2));
+            newWalk(m, branchTip), groups().put(psId(1, 1), group1).put(psId(2, 1), group2));
 
     assertThat(groups).containsEntry(a, group1);
     assertThat(groups).containsEntry(b, group2);
@@ -149,7 +148,9 @@
   public void mergeCommitMergesGroupsFromParent() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit b = tr.commit().parent(branchTip).create();
+    createRef(psId(2, 1), b, tr);
     RevCommit m = tr.commit().parent(a).parent(b).create();
 
     String group1 = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
@@ -158,7 +159,6 @@
     SortedSetMultimap<ObjectId, String> groups =
         collectGroups(
             newWalk(m, branchTip),
-            patchSets().put(a, psId(1, 1)).put(b, psId(2, 1)),
             groups().put(psId(1, 1), group1).put(psId(2, 1), group2a).put(psId(2, 1), group2b));
 
     assertThat(groups).containsEntry(a, group1);
@@ -171,12 +171,12 @@
   public void mergeCommitWithOneUninterestingParentAndOtherParentIsExisting() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit m = tr.commit().parent(branchTip).parent(a).create();
 
     String group = "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef";
     SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(
-            newWalk(m, branchTip), patchSets().put(a, psId(1, 1)), groups().put(psId(1, 1), group));
+        collectGroups(newWalk(m, branchTip), groups().put(psId(1, 1), group));
 
     assertThat(groups).containsEntry(a, group);
     assertThat(groups).containsEntry(m, group);
@@ -188,8 +188,7 @@
     RevCommit a = tr.commit().parent(branchTip).create();
     RevCommit m = tr.commit().parent(branchTip).parent(a).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(m, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(m, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(m, a.name());
@@ -204,8 +203,7 @@
     RevCommit m1 = tr.commit().parent(b).parent(c).create();
     RevCommit m2 = tr.commit().parent(a).parent(m1).create();
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(m2, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(m2, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(b, a.name());
@@ -223,8 +221,7 @@
     assertThat(m.getParentCount()).isEqualTo(2);
     assertThat(m.getParent(0)).isEqualTo(m.getParent(1));
 
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(newWalk(m, branchTip), patchSets(), groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(newWalk(m, branchTip), groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(m, a.name());
@@ -234,7 +231,9 @@
   public void mergeCommitWithOneNewParentAndTwoExistingPatchSets() throws Exception {
     RevCommit branchTip = tr.commit().create();
     RevCommit a = tr.commit().parent(branchTip).create();
+    createRef(psId(1, 1), a, tr);
     RevCommit b = tr.commit().parent(branchTip).create();
+    createRef(psId(2, 1), b, tr);
     RevCommit c = tr.commit().parent(b).create();
     RevCommit m = tr.commit().parent(a).parent(c).create();
 
@@ -242,9 +241,7 @@
     String group2 = "1234567812345678123456781234567812345678";
     SortedSetMultimap<ObjectId, String> groups =
         collectGroups(
-            newWalk(m, branchTip),
-            patchSets().put(a, psId(1, 1)).put(b, psId(2, 1)),
-            groups().put(psId(1, 1), group1).put(psId(2, 1), group2));
+            newWalk(m, branchTip), groups().put(psId(1, 1), group1).put(psId(2, 1), group2));
 
     assertThat(groups).containsEntry(a, group1);
     assertThat(groups).containsEntry(b, group2);
@@ -264,16 +261,7 @@
     rw.markStart(rw.parseCommit(d));
     // Schema upgrade case: all commits are existing patch sets, but none have
     // groups assigned yet.
-    SortedSetMultimap<ObjectId, String> groups =
-        collectGroups(
-            rw,
-            patchSets()
-                .put(branchTip, psId(1, 1))
-                .put(a, psId(2, 1))
-                .put(b, psId(3, 1))
-                .put(c, psId(4, 1))
-                .put(d, psId(5, 1)),
-            groups());
+    SortedSetMultimap<ObjectId, String> groups = collectGroups(rw, groups());
 
     assertThat(groups).containsEntry(a, a.name());
     assertThat(groups).containsEntry(b, a.name());
@@ -287,6 +275,13 @@
     return PatchSet.id(Change.id(c), p);
   }
 
+  private static void createRef(PatchSet.Id psId, ObjectId id, TestRepository<?> tr)
+      throws IOException {
+    RefUpdate ru = tr.getRepository().updateRef(psId.toRefName());
+    ru.setNewObjectId(id);
+    assertThat(ru.update()).isEqualTo(RefUpdate.Result.NEW);
+  }
+
   private RevWalk newWalk(ObjectId start, ObjectId branchTip) throws Exception {
     // Match RevWalk conditions from ReceiveCommits.
     RevWalk rw = new RevWalk(tr.getRepository());
@@ -297,12 +292,12 @@
     return rw;
   }
 
-  private static SortedSetMultimap<ObjectId, String> collectGroups(
-      RevWalk rw,
-      ImmutableListMultimap.Builder<ObjectId, PatchSet.Id> patchSetsBySha,
-      ImmutableListMultimap.Builder<PatchSet.Id, String> groupLookup)
-      throws Exception {
-    GroupCollector gc = new GroupCollector(patchSetsBySha.build(), groupLookup.build());
+  private SortedSetMultimap<ObjectId, String> collectGroups(
+      RevWalk rw, ImmutableListMultimap.Builder<PatchSet.Id, String> groupLookup) throws Exception {
+    ImmutableListMultimap<PatchSet.Id, String> groups = groupLookup.build();
+    GroupCollector gc =
+        new GroupCollector(
+            ReceivePackRefCache.noCache(tr.getRepository().getRefDatabase()), (s) -> groups.get(s));
     RevCommit c;
     while ((c = rw.next()) != null) {
       gc.visit(c);
@@ -310,12 +305,6 @@
     return gc.getGroups();
   }
 
-  // Helper methods for constructing various map arguments, to avoid lots of
-  // type specifications.
-  private static ImmutableListMultimap.Builder<ObjectId, PatchSet.Id> patchSets() {
-    return ImmutableListMultimap.builder();
-  }
-
   private static ImmutableListMultimap.Builder<PatchSet.Id, String> groups() {
     return ImmutableListMultimap.builder();
   }
diff --git a/javatests/com/google/gerrit/server/git/receive/ReceivePackRefCacheTest.java b/javatests/com/google/gerrit/server/git/receive/ReceivePackRefCacheTest.java
new file mode 100644
index 0000000..698acd8
--- /dev/null
+++ b/javatests/com/google/gerrit/server/git/receive/ReceivePackRefCacheTest.java
@@ -0,0 +1,140 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.git.receive;
+
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoMoreInteractions;
+import static org.mockito.Mockito.when;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
+import com.google.gerrit.entities.Change;
+import com.google.gerrit.entities.RefNames;
+import java.util.Map;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectIdRef;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.RefDatabase;
+import org.junit.Test;
+
+/** Tests for {@link ReceivePackRefCache}. */
+public class ReceivePackRefCacheTest {
+
+  @Test
+  public void noCache_prefixDelegatesToRefDb() throws Exception {
+    Ref ref = newRef("refs/changes/01/1/1", "badc0feebadc0feebadc0feebadc0feebadc0fee");
+    RefDatabase mockRefDb = mock(RefDatabase.class);
+    ReceivePackRefCache cache = ReceivePackRefCache.noCache(mockRefDb);
+    when(mockRefDb.getRefsByPrefix(RefNames.REFS_HEADS)).thenReturn(ImmutableList.of(ref));
+
+    assertThat(cache.byPrefix(RefNames.REFS_HEADS)).containsExactly(ref);
+    verify(mockRefDb).getRefsByPrefix(RefNames.REFS_HEADS);
+    verifyNoMoreInteractions(mockRefDb);
+  }
+
+  @Test
+  public void noCache_exactRefDelegatesToRefDb() throws Exception {
+    Ref ref = newRef("refs/changes/01/1/1", "badc0feebadc0feebadc0feebadc0feebadc0fee");
+    RefDatabase mockRefDb = mock(RefDatabase.class);
+    ReceivePackRefCache cache = ReceivePackRefCache.noCache(mockRefDb);
+    when(mockRefDb.exactRef("refs/heads/master")).thenReturn(ref);
+
+    assertThat(cache.exactRef("refs/heads/master")).isEqualTo(ref);
+    verify(mockRefDb).exactRef("refs/heads/master");
+    verifyNoMoreInteractions(mockRefDb);
+  }
+
+  @Test
+  public void noCache_tipsFromObjectIdDelegatesToRefDbAndFiltersByPrefix() throws Exception {
+    Ref refBla = newRef("refs/bla", "badc0feebadc0feebadc0feebadc0feebadc0fee");
+    Ref refheads = newRef(RefNames.REFS_HEADS, "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef");
+
+    RefDatabase mockRefDb = mock(RefDatabase.class);
+    ReceivePackRefCache cache = ReceivePackRefCache.noCache(mockRefDb);
+    when(mockRefDb.getTipsWithSha1(ObjectId.zeroId()))
+        .thenReturn(ImmutableSet.of(refBla, refheads));
+
+    assertThat(cache.tipsFromObjectId(ObjectId.zeroId(), RefNames.REFS_HEADS))
+        .containsExactly(refheads);
+    verify(mockRefDb).getTipsWithSha1(ObjectId.zeroId());
+    verifyNoMoreInteractions(mockRefDb);
+  }
+
+  @Test
+  public void advertisedRefs_prefixScans() throws Exception {
+    Ref refBla =
+        new ObjectIdRef.Unpeeled(
+            Ref.Storage.NEW,
+            "refs/bla/1",
+            ObjectId.fromString("badc0feebadc0feebadc0feebadc0feebadc0fee"),
+            1);
+    ReceivePackRefCache cache =
+        ReceivePackRefCache.withAdvertisedRefs(() -> ImmutableMap.of(refBla.getName(), refBla));
+
+    assertThat(cache.byPrefix("refs/bla")).containsExactly(refBla);
+  }
+
+  @Test
+  public void advertisedRefs_prefixScansChangeId() throws Exception {
+    Map<String, Ref> refs = setupTwoChanges();
+    ReceivePackRefCache cache = ReceivePackRefCache.withAdvertisedRefs(() -> refs);
+
+    assertThat(cache.byPrefix(RefNames.changeRefPrefix(Change.id(1))))
+        .containsExactly(refs.get("refs/changes/01/1/1"));
+  }
+
+  @Test
+  public void advertisedRefs_exactRef() throws Exception {
+    Map<String, Ref> refs = setupTwoChanges();
+    ReceivePackRefCache cache = ReceivePackRefCache.withAdvertisedRefs(() -> refs);
+
+    assertThat(cache.exactRef("refs/changes/01/1/1")).isEqualTo(refs.get("refs/changes/01/1/1"));
+  }
+
+  @Test
+  public void advertisedRefs_tipsFromObjectIdWithNoPrefix() throws Exception {
+    Map<String, Ref> refs = setupTwoChanges();
+    ReceivePackRefCache cache = ReceivePackRefCache.withAdvertisedRefs(() -> refs);
+
+    assertThat(
+            cache.tipsFromObjectId(
+                ObjectId.fromString("badc0feebadc0feebadc0feebadc0feebadc0fee"), null))
+        .containsExactly(refs.get("refs/changes/01/1/1"));
+  }
+
+  @Test
+  public void advertisedRefs_tipsFromObjectIdWithPrefix() throws Exception {
+    Map<String, Ref> refs = setupTwoChanges();
+    ReceivePackRefCache cache = ReceivePackRefCache.withAdvertisedRefs(() -> refs);
+
+    assertThat(
+            cache.tipsFromObjectId(
+                ObjectId.fromString("badc0feebadc0feebadc0feebadc0feebadc0fee"), "/refs/some"))
+        .isEmpty();
+  }
+
+  private static Ref newRef(String name, String sha1) {
+    return new ObjectIdRef.Unpeeled(Ref.Storage.NEW, name, ObjectId.fromString(sha1), 1);
+  }
+
+  private Map<String, Ref> setupTwoChanges() {
+    Ref ref1 = newRef("refs/changes/01/1/1", "badc0feebadc0feebadc0feebadc0feebadc0fee");
+    Ref ref2 = newRef("refs/changes/02/2/1", "deadbeefdeadbeefdeadbeefdeadbeefdeadbeef");
+    return ImmutableMap.of(ref1.getName(), ref1, ref2.getName(), ref2);
+  }
+}
diff --git a/javatests/com/google/gerrit/server/index/change/FakeQueryBuilder.java b/javatests/com/google/gerrit/server/index/change/FakeQueryBuilder.java
index 0753127..3dfbefe 100644
--- a/javatests/com/google/gerrit/server/index/change/FakeQueryBuilder.java
+++ b/javatests/com/google/gerrit/server/index/change/FakeQueryBuilder.java
@@ -18,6 +18,7 @@
 import com.google.gerrit.index.query.Predicate;
 import com.google.gerrit.server.query.change.ChangeData;
 import com.google.gerrit.server.query.change.ChangeQueryBuilder;
+import org.eclipse.jgit.lib.Config;
 import org.junit.Ignore;
 
 @Ignore
@@ -26,8 +27,34 @@
     super(
         new ChangeQueryBuilder.Definition<>(FakeQueryBuilder.class),
         new ChangeQueryBuilder.Arguments(
-            null, null, null, null, null, null, null, null, null, null, null, null, null, null,
-            null, null, null, null, indexes, null, null, null, null, null, null, null));
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            indexes,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            null,
+            new Config()));
   }
 
   @Operator
diff --git a/javatests/com/google/gerrit/server/index/change/StalenessCheckerTest.java b/javatests/com/google/gerrit/server/index/change/StalenessCheckerTest.java
index c887875..6f40680 100644
--- a/javatests/com/google/gerrit/server/index/change/StalenessCheckerTest.java
+++ b/javatests/com/google/gerrit/server/index/change/StalenessCheckerTest.java
@@ -163,34 +163,37 @@
     // Not stale.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id1.name()),
-                    P2, RefState.create(ref2, id2.name())),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id1.name()),
+                        P2, RefState.create(ref2, id2.name())),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isFalse();
 
     // Wrong ref value.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, SHA1),
-                    P2, RefState.create(ref2, id2.name())),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, SHA1),
+                        P2, RefState.create(ref2, id2.name())),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isTrue();
 
     // Swapped repos.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id2.name()),
-                    P2, RefState.create(ref2, id1.name())),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id2.name()),
+                        P2, RefState.create(ref2, id1.name())),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isTrue();
 
     // Two refs in same repo, not stale.
@@ -199,32 +202,35 @@
     tr1.update(ref3, id3);
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id1.name()),
-                    P1, RefState.create(ref3, id3.name())),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id1.name()),
+                        P1, RefState.create(ref3, id3.name())),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isFalse();
 
     // Ignore ref not mentioned.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isFalse();
 
     // One ref wrong.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id1.name()),
-                    P1, RefState.create(ref3, SHA1)),
-                ImmutableListMultimap.of()))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id1.name()),
+                        P1, RefState.create(ref3, SHA1)),
+                    ImmutableListMultimap.of())
+                .isStale())
         .isTrue();
   }
 
@@ -236,10 +242,11 @@
     // ref1 is only ref matching pattern.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*")))
+                .isStale())
         .isFalse();
 
     // Now ref2 matches pattern, so stale unless ref2 is present in state map.
@@ -247,19 +254,21 @@
     ObjectId id2 = tr1.update(ref2, tr1.commit().message("commit 2"));
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*")))
+                .isStale())
         .isTrue();
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id1.name()),
-                    P1, RefState.create(ref2, id2.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id1.name()),
+                        P1, RefState.create(ref2, id2.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/heads/*")))
+                .isStale())
         .isFalse();
   }
 
@@ -272,10 +281,11 @@
     // ref1 is only ref matching pattern.
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo")))
+                .isStale())
         .isFalse();
 
     // Now ref2 matches pattern, so stale unless ref2 is present in state map.
@@ -283,19 +293,21 @@
     ObjectId id3 = tr1.update(ref3, tr1.commit().message("commit 3"));
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(P1, RefState.create(ref1, id1.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo")))
+                .isStale())
         .isTrue();
     assertThat(
             refsAreStale(
-                repoManager,
-                C,
-                ImmutableSetMultimap.of(
-                    P1, RefState.create(ref1, id1.name()),
-                    P1, RefState.create(ref3, id3.name())),
-                ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo"))))
+                    repoManager,
+                    C,
+                    ImmutableSetMultimap.of(
+                        P1, RefState.create(ref1, id1.name()),
+                        P1, RefState.create(ref3, id3.name())),
+                    ImmutableListMultimap.of(P1, RefStatePattern.create("refs/*/foo")))
+                .isStale())
         .isFalse();
   }
 
diff --git a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
index 2c5fcc4..962b691 100644
--- a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
@@ -41,6 +41,7 @@
 import com.google.common.collect.Lists;
 import com.google.common.collect.Streams;
 import com.google.common.truth.ThrowableSubject;
+import com.google.gerrit.acceptance.config.GerritConfig;
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.common.data.LabelType;
@@ -79,6 +80,7 @@
 import com.google.gerrit.index.IndexConfig;
 import com.google.gerrit.index.Schema;
 import com.google.gerrit.index.query.Predicate;
+import com.google.gerrit.index.query.QueryParseException;
 import com.google.gerrit.lifecycle.LifecycleManager;
 import com.google.gerrit.server.AnonymousUser;
 import com.google.gerrit.server.CurrentUser;
@@ -2023,6 +2025,7 @@
   }
 
   @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "true")
   public void mergeable() throws Exception {
     TestRepository<Repo> repo = createProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "contents1").create());
@@ -2040,7 +2043,7 @@
     // If a change gets submitted, the remaining open changes get reindexed asynchronously to update
     // their mergeability information. If the further assertions in this test are done before the
     // asynchronous reindex completed they fail because the mergeability information in the index
-    // was not updated yet. To avoid this flakiness reindexAfterRefUpdate is switched off for the
+    // was not updated yet. To avoid this flakiness indexMergeable is switched off for the
     // tests and we index change2 synchronously here.
     gApi.changes().id(change2.getChangeId()).index();
 
@@ -2502,6 +2505,19 @@
     assertQueryByIds("revertof:" + changeToRevert._number, Change.id(changeThatReverts._number));
   }
 
+  @Test
+  public void submissionId() throws Exception {
+    TestRepository<Repo> repo = createProject("repo");
+    Change change = insert(repo, newChange(repo));
+    // create irrelevant change
+    insert(repo, newChange(repo));
+    gApi.changes().id(change.getChangeId()).current().review(ReviewInput.approve());
+    gApi.changes().id(change.getChangeId()).current().submit();
+    String submissionId = gApi.changes().id(change.getChangeId()).get().submissionId;
+
+    assertQueryByIds("submissionid:" + submissionId, change.getId());
+  }
+
   /** Change builder for helping in tests for dashboard sections. */
   protected class DashboardChangeState {
     private final Account.Id ownerId;
@@ -3066,6 +3082,20 @@
     }
   }
 
+  @Test
+  @GerritConfig(name = "index.change.indexMergeable", value = "false")
+  public void mergeableFailsWhenNotIndexed() throws Exception {
+    TestRepository<Repo> repo = createProject("repo");
+    RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "contents1").create());
+    insert(repo, newChangeForCommit(repo, commit1));
+
+    Throwable thrown = assertThrows(Throwable.class, () -> assertQuery("status:open is:mergeable"));
+    assertThat(thrown.getCause()).isInstanceOf(QueryParseException.class);
+    assertThat(thrown)
+        .hasMessageThat()
+        .contains("server does not support 'mergeable'. check configs");
+  }
+
   protected ChangeInserter newChange(TestRepository<Repo> repo) throws Exception {
     return newChange(repo, null, null, null, null, false);
   }
diff --git a/javatests/com/google/gerrit/server/query/change/BUILD b/javatests/com/google/gerrit/server/query/change/BUILD
index d0162d3..e5b51e7 100644
--- a/javatests/com/google/gerrit/server/query/change/BUILD
+++ b/javatests/com/google/gerrit/server/query/change/BUILD
@@ -16,12 +16,14 @@
         "//prolog:gerrit-prolog-common",
     ],
     deps = [
+        "//java/com/google/gerrit/acceptance/config",
         "//java/com/google/gerrit/acceptance/testsuite/project",
         "//java/com/google/gerrit/common:annotations",
         "//java/com/google/gerrit/common:server",
         "//java/com/google/gerrit/entities",
         "//java/com/google/gerrit/extensions:api",
         "//java/com/google/gerrit/index",
+        "//java/com/google/gerrit/index:query_exception",
         "//java/com/google/gerrit/lifecycle",
         "//java/com/google/gerrit/server",
         "//java/com/google/gerrit/server/project/testing:project-test-util",
diff --git a/javatests/com/google/gerrit/server/util/git/BUILD b/javatests/com/google/gerrit/server/util/git/BUILD
index 883898f..b789dff 100644
--- a/javatests/com/google/gerrit/server/util/git/BUILD
+++ b/javatests/com/google/gerrit/server/util/git/BUILD
@@ -18,7 +18,6 @@
         "//lib:protobuf",
         "//lib/auto:auto-value",
         "//lib/auto:auto-value-annotations",
-        "//lib/commons:codec",
         "//lib/guice",
         "//lib/truth",
         "//lib/truth:truth-java8-extension",
diff --git a/lib/BUILD b/lib/BUILD
index 13580b1..39c622a 100644
--- a/lib/BUILD
+++ b/lib/BUILD
@@ -1,4 +1,4 @@
-load("@rules_java//java:defs.bzl", "java_library")
+load("@rules_java//java:defs.bzl", "java_import", "java_library")
 
 exports_files(glob([
     "LICENSE-*",
@@ -111,6 +111,29 @@
 )
 
 java_library(
+    name = "caffeine",
+    data = ["//lib:LICENSE-Apache2.0"],
+    visibility = [
+        "//java/com/google/gerrit/server/cache/mem:__pkg__",
+    ],
+    exports = ["@caffeine//jar"],
+)
+
+java_import(
+    name = "caffeine-guava-renamed",
+    jars = ["@caffeine-guava-renamed//file"],
+)
+
+java_library(
+    name = "caffeine-guava",
+    data = ["//lib:LICENSE-Apache2.0"],
+    visibility = [
+        "//java/com/google/gerrit/server/cache/mem:__pkg__",
+    ],
+    exports = [":caffeine-guava-renamed"],
+)
+
+java_library(
     name = "jsch",
     data = ["//lib:LICENSE-jsch"],
     visibility = ["//visibility:public"],
diff --git a/lib/jetty/BUILD b/lib/jetty/BUILD
index 6417385..fe07794 100644
--- a/lib/jetty/BUILD
+++ b/lib/jetty/BUILD
@@ -21,7 +21,6 @@
     data = ["//lib:LICENSE-Apache2.0"],
     visibility = ["//visibility:public"],
     exports = [
-        ":continuation",
         ":http",
         "@jetty-server//jar",
     ],
@@ -32,20 +31,12 @@
     data = ["//lib:LICENSE-Apache2.0"],
     visibility = ["//visibility:public"],
     exports = [
-        ":continuation",
         ":http",
         "@jetty-jmx//jar",
     ],
 )
 
 java_library(
-    name = "continuation",
-    data = ["//lib:LICENSE-Apache2.0"],
-    visibility = ["//visibility:public"],
-    exports = ["@jetty-continuation//jar"],
-)
-
-java_library(
     name = "http",
     data = ["//lib:LICENSE-Apache2.0"],
     visibility = ["//visibility:public"],
diff --git a/modules/jgit b/modules/jgit
index 63fc697..0356613 160000
--- a/modules/jgit
+++ b/modules/jgit
@@ -1 +1 @@
-Subproject commit 63fc6970cc51b712608d93e7cba0b85bb559ac52
+Subproject commit 0356613f48ebee2e3d2d65780e71d9e0b43a752e
diff --git a/package.json b/package.json
index 6b9a38d..5ed4671 100644
--- a/package.json
+++ b/package.json
@@ -4,11 +4,11 @@
   "description": "Gerrit Code Review",
   "dependencies": {},
   "devDependencies": {
-    "eslint": "^5.16.0",
+    "eslint": "^6.6.0",
     "eslint-config-google": "^0.13.0",
-    "eslint-plugin-html": "^5.0.5",
+    "eslint-plugin-html": "^6.0.0",
     "fried-twinkie": "^0.2.2",
-    "polylint": "^2.10.4",
+    "polymer-cli": "^1.9.11",
     "typescript": "^2.x.x",
     "web-component-tester": "^6.5.0"
   },
@@ -16,6 +16,7 @@
     "start": "polygerrit-ui/run-server.sh",
     "test": "WCT_HEADLESS_MODE=1 WCT_ARGS='--verbose -l chrome' ./polygerrit-ui/app/run_test.sh",
     "eslint": "./node_modules/eslint/bin/eslint.js --ignore-pattern 'bower_components/' --ignore-pattern 'gr-linked-text' --ignore-pattern 'scripts/vendor' --ext .html,.js polygerrit-ui/app || exit 0",
+    "eslintfix": "./node_modules/eslint/bin/eslint.js --fix --ignore-pattern 'bower_components/' --ignore-pattern 'gr-linked-text' --ignore-pattern 'scripts/vendor' --ext .html,.js polygerrit-ui/app || exit 0",
     "test-template": "./polygerrit-ui/app/run_template_test.sh",
     "polylint": "bazel test polygerrit-ui/app:polylint_test"
   },
diff --git a/plugins/codemirror-editor b/plugins/codemirror-editor
index 92ce310..9508693 160000
--- a/plugins/codemirror-editor
+++ b/plugins/codemirror-editor
@@ -1 +1 @@
-Subproject commit 92ce310ecf717133601b9e824c38bc5e5eafecba
+Subproject commit 9508693bd0a85560674143256314beac08f2d8ca
diff --git a/plugins/delete-project b/plugins/delete-project
index 881e409..38f4fde 160000
--- a/plugins/delete-project
+++ b/plugins/delete-project
@@ -1 +1 @@
-Subproject commit 881e409080a7a257175e736b952ab78dab51be9d
+Subproject commit 38f4fde24ce24cf1bf8d1e4d074f1d784ed983b8
diff --git a/plugins/hooks b/plugins/hooks
index 22d1dbb..6316be2 160000
--- a/plugins/hooks
+++ b/plugins/hooks
@@ -1 +1 @@
-Subproject commit 22d1dbbbd2b34dc066e20e6fb26a8623f1ae47fc
+Subproject commit 6316be2828808dafc546ecd11c055396d0b4951b
diff --git a/plugins/plugin-manager b/plugins/plugin-manager
index c921234..828d666 160000
--- a/plugins/plugin-manager
+++ b/plugins/plugin-manager
@@ -1 +1 @@
-Subproject commit c921234cec4c0d058b35a8d117f55fce4d4c5e65
+Subproject commit 828d666bbb4aae1a2c348a12d7855ec5db3be46f
diff --git a/plugins/replication b/plugins/replication
index 5e3cbc8..d7c09fb 160000
--- a/plugins/replication
+++ b/plugins/replication
@@ -1 +1 @@
-Subproject commit 5e3cbc8e7e45172790e777ec0576b08b65934b09
+Subproject commit d7c09fbb4c18b1743d6060d361171c2a5237f22b
diff --git a/polygerrit-ui/README.md b/polygerrit-ui/README.md
index a73f243..461e2b9 100644
--- a/polygerrit-ui/README.md
+++ b/polygerrit-ui/README.md
@@ -64,14 +64,16 @@
 The biggest draw back of this method is that you cannot log in, so cannot test
 scenarios that require it.
 
-#### MITM Proxy
+#### Chrome extension: Gerrit FE Dev Helper
 
-[MITM Proxy](https://mitmproxy.org/) is an open source product for proxying
-https servers. The
-[contrib/mitm-ui/](https://gerrit.googlesource.com/gerrit/+/master/contrib/mitm-ui/)
-directory contains scripts (and documentation) for using this technology
-(instead of the Go server). These scripts are somewhat experimental and
-unmaintained though.
+To be able to bypass the auth and also help improve the productivity of Gerrit FE developers,
+we created this chrome extension: [Gerrit FE Dev Helper](https://chrome.google.com/webstore/detail/gerrit-fe-dev-helper/jimgomcnodkialnpmienbomamgomglkd).
+
+It basically works as a proxy that will block / redirect requests from current sites to any given url base on certain rules.
+
+The source code is in [Gerrit - gerrit-fe-dev-helper](https://gerrit-review.googlesource.com/q/project:gerrit-fe-dev-helper), contributions are welcomed!
+
+To use this extension, just follow its [readme here](https://gerrit.googlesource.com/gerrit-fe-dev-helper/+/master/README.md).
 
 ## Running locally against a Gerrit test site
 
@@ -182,6 +184,11 @@
 ```
 
 ## Template Type Safety
+
+> **Warning**: This feature is temporary disabled, because it doesn't work with Polymer 2 and Polymer 3. 
+Some of the checks are made by polymer linter.
+
+
 Polymer elements are not type checked against the element definition, making it
 trivial to break the display when refactoring or moving code. We now run
 additional tests to help ensure that template types are checked.
diff --git a/polygerrit-ui/app/.eslintrc.json b/polygerrit-ui/app/.eslintrc.json
index 97151f2..8066d26 100644
--- a/polygerrit-ui/app/.eslintrc.json
+++ b/polygerrit-ui/app/.eslintrc.json
@@ -25,27 +25,36 @@
     "block-spacing": ["error", "always"],
     "brace-style": ["error", "1tbs", { "allowSingleLine": true }],
     "camelcase": "off",
-    "comma-dangle": ["error", "always-multiline"],
+    "comma-dangle": ["error", {
+      "arrays": "always-multiline",
+      "objects": "always-multiline",
+      "imports": "always-multiline",
+      "exports": "always-multiline",
+      "functions": "never"
+    }],
     "eol-last": "off",
-    "indent": "off",
-    "indent-legacy": ["error", 2, {
+    "indent": ["error", 2, {
       "MemberExpression": 2,
       "FunctionDeclaration": {"body": 1, "parameters": 2},
       "FunctionExpression": {"body": 1, "parameters": 2},
-      "CallExpression": {"arguments": 2},
+      "CallExpression": {"arguments": 2 },
       "ArrayExpression": 1,
       "ObjectExpression": 1,
       "SwitchCase": 1
     }],
     "keyword-spacing": ["error", { "after": true, "before": true }],
+    "lines-between-class-members": ["error", "always"],
     "max-len": [
       "error",
       80,
       2,
       {"ignoreComments": true}
     ],
-    "new-cap": ["error", { "capIsNewExceptions": ["Polymer"] }],
+    "new-cap": ["error", { "capIsNewExceptions": ["Polymer", "LegacyElementMixin", "GestureEventListeners", "LegacyDataMixin"] }],
     "no-console": "off",
+    "no-multiple-empty-lines": [ "error", { "max": 1 } ],
+    "no-prototype-builtins": "off",
+    "no-redeclare": "off",
     "no-restricted-syntax": [
       "error",
       {
@@ -61,6 +70,19 @@
     "no-useless-escape": "off",
     "no-var": "error",
     "object-shorthand": ["error", "always"],
+    "padding-line-between-statements": [
+      "error",
+      {
+        "blankLine": "always",
+        "prev": "class",
+        "next": "*"
+      },
+      {
+        "blankLine": "always",
+        "prev": "*",
+        "next": "class"
+      }
+    ],
     "prefer-arrow-callback": "error",
     "prefer-const": "error",
     "prefer-spread": "error",
diff --git a/polygerrit-ui/app/BUILD b/polygerrit-ui/app/BUILD
index 6d30a14..3a70ac53 100644
--- a/polygerrit-ui/app/BUILD
+++ b/polygerrit-ui/app/BUILD
@@ -46,6 +46,22 @@
 )
 
 filegroup(
+    name = "pg_code_without_test",
+    srcs = glob(
+        [
+            "**/*.html",
+            "**/*.js",
+        ],
+        exclude = [
+            "bower_components/**",
+            "**/*_test.html",
+            "test/**",
+            "samples/**",
+        ],
+    ),
+)
+
+filegroup(
     name = "bower_components",
     srcs = glob(
         [
@@ -108,7 +124,8 @@
     size = "large",
     srcs = ["polylint_test.sh"],
     data = [
-        ":pg_code",
+        "polymer.json",
+        ":pg_code_without_test",
         "//polygerrit-ui:polygerrit_components.bower_components.zip",
     ],
     # Should not run sandboxed.
@@ -148,33 +165,6 @@
     ],
 ) for directory in DIRECTORIES]
 
-# Embed bundle
-polygerrit_bundle(
-    name = "polygerrit_embed_ui",
-    srcs = glob(
-        [
-            "**/*.html",
-            "**/*.js",
-        ],
-        exclude = [
-            "bower_components/**",
-            "test/**",
-            "**/*_test.html",
-        ],
-    ),
-    outs = ["polygerrit_embed_ui.zip"],
-    app = "embed/embed.html",
-)
-
-filegroup(
-    name = "embed_test_files",
-    srcs = glob(
-        [
-            "embed/**/*_test.html",
-        ],
-    ),
-)
-
 filegroup(
     name = "template_test_srcs",
     srcs = [
@@ -182,21 +172,3 @@
         "template_test_srcs/template_test.js",
     ],
 )
-
-sh_test(
-    name = "embed_test",
-    size = "small",
-    srcs = ["embed_test.sh"],
-    data = [
-        "embed/test.html",
-        "test/common-test-setup.html",
-        ":embed_test_files",
-        ":pg_code.zip",
-        ":test_components.zip",
-    ],
-    # Should not run sandboxed.
-    tags = [
-        "local",
-        "manual",
-    ],
-)
diff --git a/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior.html b/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior.html
index 36e0201..f560ea8 100644
--- a/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior.html
+++ b/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior.html
@@ -45,5 +45,22 @@
       });
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.AsyncForeachMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior_test.html b/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior_test.html
index 970bfc7..03ba6b1 100644
--- a/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/async-foreach-behavior/async-foreach-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>async-foreach-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior.html b/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior.html
index 1748647..92596e0 100644
--- a/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior.html
+++ b/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior.html
@@ -28,5 +28,22 @@
       return window.CANONICAL_PATH || '';
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.BaseUrlMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior_test.html b/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior_test.html
index b61b142..5669bc4 100644
--- a/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/base-url-behavior/base-url-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>base-url-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior.html b/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior.html
index 64b725f..3361bc8 100644
--- a/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior.html
+++ b/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior.html
@@ -56,7 +56,24 @@
       cachedPromise = undefined;
     },
   },
-    Gerrit.BaseUrlBehavior,
+  Gerrit.BaseUrlBehavior,
   ];
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.DocsUrlMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior_test.html b/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior_test.html
index 2c513f3..e554012 100644
--- a/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/docs-url-behavior/docs-url-behavior_test.html
@@ -19,7 +19,7 @@
 <script src="/bower_components/web-component-tester/browser.js"></script>
 <link rel="import" href="../../test/common-test-setup.html"/>
 <title>docs-url-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <link rel="import" href="docs-url-behavior.html">
diff --git a/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior.html b/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior.html
index 2d25b29..5daa032 100644
--- a/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior.html
+++ b/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior.html
@@ -42,5 +42,22 @@
       return isDescendant;
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.DomUtilMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior_test.html b/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior_test.html
index 8323ac6..a52e0e2 100644
--- a/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/dom-util-behavior/dom-util-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>dom-util-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/fire-behavior/fire-behavior.html b/polygerrit-ui/app/behaviors/fire-behavior/fire-behavior.html
index b5afab1..5b3d420 100644
--- a/polygerrit-ui/app/behaviors/fire-behavior/fire-behavior.html
+++ b/polygerrit-ui/app/behaviors/fire-behavior/fire-behavior.html
@@ -51,5 +51,22 @@
       return event;
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.FireMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior.html b/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior.html
index 0c75c44..9d3b1af 100644
--- a/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior.html
@@ -150,5 +150,29 @@
       });
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.AccessMixin = base =>
+      class extends base {
+        static get properties() {
+          return {
+            permissionValues: {
+              type: Object,
+            },
+          };
+        }
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior_test.html b/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior_test.html
index 0d1ee57..48565a6 100644
--- a/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-access-behavior/gr-access-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.html b/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.html
index 182d242..07350b9 100644
--- a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior.html
@@ -201,5 +201,22 @@
       };
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.AdminNavMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.html b/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.html
index 0285e35..25b75c8 100644
--- a/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-admin-nav-behavior/gr-admin-nav-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -310,7 +310,6 @@
       });
     });
 
-
     suite('view plugin screen with plugin capability', () => {
       const account = {
         name: 'test-user',
@@ -337,7 +336,6 @@
       });
     });
 
-
     suite('view plugin screen without plugin capability', () => {
       const account = {
         name: 'test-user',
diff --git a/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior.html b/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior.html
index c462c6f..db35a67 100644
--- a/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior.html
@@ -75,5 +75,31 @@
       return newColumns;
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.ChangeTableMixin = base =>
+      class extends base {
+        static get properties() {
+          return {
+            columnNames: {
+              type: Array,
+            },
+          };
+        }
+
+        isColumnHidden(columnToCheck, columnsToDisplay) {}
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior_test.html b/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior_test.html
index 791e2af..52931bc 100644
--- a/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-change-table-behavior/gr-change-table-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior.html b/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior.html
index 3106fc8..e5ded0e 100644
--- a/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior.html
@@ -39,5 +39,22 @@
       return GrDisplayNameUtils.getGroupDisplayName(group);
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.DisplayNameMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior_test.html b/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior_test.html
index 3d4eca1..aa217a1 100644
--- a/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-display-name-behavior/gr-display-name-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-display-name-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior.html b/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior.html
index f251db8..06912d5 100644
--- a/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior.html
@@ -56,8 +56,29 @@
       return 0;
     },
   },
-    Gerrit.BaseUrlBehavior,
-    Gerrit.URLEncodingBehavior,
+  Gerrit.BaseUrlBehavior,
+  Gerrit.URLEncodingBehavior,
   ];
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.ListViewMixin = base =>
+      class extends base {
+        computeLoadingClass(loading) {}
+
+        computeShownItems(items) {}
+      };
+  }
 })(window);
+
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior_test.html b/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior_test.html
index 535483d..9b48cdc 100644
--- a/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-list-view-behavior/gr-list-view-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior.html b/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior.html
index 0b5c340..c2ca081 100644
--- a/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior.html
@@ -124,8 +124,8 @@
       // 2 -> 3, 3 -> 5, etc.
       // Map an edit to the patchNum of parent*2... I.e. edit on 2 -> 4.
       const num = r => r._number === Gerrit.PatchSetBehavior.EDIT_NAME ?
-          2 * editParent :
-          2 * (r._number - 1) + 1;
+        2 * editParent :
+        2 * (r._number - 1) + 1;
       return revisions.sort((a, b) => num(b) - num(a));
     },
 
@@ -272,5 +272,29 @@
       return -parseInt(rangeBase + '', 10);
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.PatchSetMixin = base =>
+      class extends base {
+        computeLatestPatchNum(allPatchSets) {}
+
+        hasEditPatchsetLoaded(patchRangeRecord) {}
+
+        hasEditBasedOnCurrentPatchSet(allPatchSets) {}
+
+        computeAllPatchSets(change) {}
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior_test.html b/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior_test.html
index 3db4084..5e70179 100644
--- a/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-patch-set-behavior/gr-patch-set-behavior_test.html
@@ -19,7 +19,7 @@
 <script src="/bower_components/web-component-tester/browser.js"></script>
 <link rel="import" href="../../test/common-test-setup.html"/>
 <title>gr-patch-set-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <link rel="import" href="gr-patch-set-behavior.html">
diff --git a/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior.html b/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior.html
index 5e597ae..8f9bf00 100644
--- a/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior.html
@@ -110,5 +110,25 @@
       return `\u2026/${pathPieces.slice(index).join('/')}`;
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.PathListMixin = base =>
+      class extends base {
+        computeDisplayPath(path) {}
+
+        computeTruncatedPath(path) {}
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior_test.html b/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior_test.html
index 0046290..924c98c 100644
--- a/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-path-list-behavior/gr-path-list-behavior_test.html
@@ -19,7 +19,7 @@
 <script src="/bower_components/web-component-tester/browser.js"></script>
 <link rel="import" href="../../test/common-test-setup.html"/>
 <title>gr-path-list-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <link rel="import" href="gr-path-list-behavior.html">
diff --git a/polygerrit-ui/app/behaviors/gr-repo-plugin-config-behavior/gr-repo-plugin-config-behavior.html b/polygerrit-ui/app/behaviors/gr-repo-plugin-config-behavior/gr-repo-plugin-config-behavior.html
index 2fa9191..69ebf23 100644
--- a/polygerrit-ui/app/behaviors/gr-repo-plugin-config-behavior/gr-repo-plugin-config-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-repo-plugin-config-behavior/gr-repo-plugin-config-behavior.html
@@ -34,5 +34,22 @@
     },
     PLUGIN_CONFIG_CHANGED: 'plugin-config-changed',
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.RepoPluginConfigMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior.js b/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior.js
index 0bf620f..73b8261 100644
--- a/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior.js
+++ b/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior.js
@@ -146,4 +146,28 @@
       }
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.TooltipMixin = base =>
+      class extends base {
+        static get properties() {
+          return {
+            hasTooltip: {
+              type: Boolean,
+            },
+          };
+        }
+      };
+  }
 })(window);
diff --git a/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior_test.html b/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior_test.html
index 173c8d4..f3354a4 100644
--- a/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior_test.html
@@ -17,7 +17,7 @@
 -->
 
 <title>tooltip-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior.html b/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior.html
index 69703f6..c4979b5 100644
--- a/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior.html
+++ b/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior.html
@@ -53,5 +53,22 @@
       return decodeURIComponent(withoutPlus);
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.URLEncodingMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior_test.html b/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior_test.html
index 73e51d3..6cf2c68 100644
--- a/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/gr-url-encoding-behavior/gr-url-encoding-behavior_test.html
@@ -17,7 +17,7 @@
 -->
 
 <title>gr-url-encoding-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html
index 3c5a733..d4e2c72 100644
--- a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html
+++ b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html
@@ -612,5 +612,22 @@
       shortcutManager.bindShortcut(shortcut, ...bindings);
     },
   };
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.KeyboardShortcutMixin = base =>
+      class extends base {
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior_test.html b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior_test.html
index 5a563ab..ba143ec 100644
--- a/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -240,8 +240,8 @@
 
         test('directory view', () => {
           const {
-              NEXT_FILE, NEXT_LINE, GO_TO_OPENED_CHANGES, SEARCH,
-              SAVE_COMMENT,
+            NEXT_FILE, NEXT_LINE, GO_TO_OPENED_CHANGES, SEARCH,
+            SAVE_COMMENT,
           } = kb.Shortcut;
           const {DIFFS, EVERYWHERE, NAVIGATION} = kb.ShortcutSection;
           const {GO_KEY, ShortcutManager} = kb;
diff --git a/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior.html b/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior.html
index 4252e6e..27041f7 100644
--- a/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior.html
+++ b/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior.html
@@ -175,7 +175,27 @@
       return this.changeStatuses(change).join(', ');
     },
   },
-    Gerrit.BaseUrlBehavior,
+  Gerrit.BaseUrlBehavior,
   ];
+
+  // eslint-disable-next-line no-unused-vars
+  function defineEmptyMixin() {
+    // This is a temporary function.
+    // Polymer linter doesn't process correctly the following code:
+    // class MyElement extends Polymer.mixinBehaviors([legacyBehaviors], ...) {...}
+    // To workaround this issue, the mock mixin is declared in this method.
+    // In the following changes, legacy behaviors will be converted to mixins.
+
+    /**
+     * @polymer
+     * @mixinFunction
+     */
+    Gerrit.RESTClientMixin = base =>
+      class extends base {
+        changeStatusString(change) {}
+
+        changeStatuses(change, opt_options) {}
+      };
+  }
 })(window);
 </script>
diff --git a/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior_test.html b/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior_test.html
index a77a01f..cfcc11e 100644
--- a/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/rest-client-behavior/rest-client-behavior_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>keyboard-shortcut-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/behaviors/safe-types-behavior/safe-types-behavior_test.html b/polygerrit-ui/app/behaviors/safe-types-behavior/safe-types-behavior_test.html
index ab446f1..7351647 100644
--- a/polygerrit-ui/app/behaviors/safe-types-behavior/safe-types-behavior_test.html
+++ b/polygerrit-ui/app/behaviors/safe-types-behavior/safe-types-behavior_test.html
@@ -17,7 +17,7 @@
 -->
 
 <title>safe-types-behavior</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.html b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.html
index ac65360..a52cb1a 100644
--- a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.html
+++ b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.html
@@ -86,7 +86,9 @@
         padding-right: var(--spacing-m);
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <fieldset id="section"
         class$="gr-form-styles [[_computeSectionClass(editing, canUpload, ownerOf, _editingRef, _deleted)]]">
       <div id="mainContainer">
diff --git a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.js b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.js
index b6f1b74..158e20b 100644
--- a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.js
+++ b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section.js
@@ -36,61 +36,69 @@
   const ON_BEHALF_OF = '(On Behalf Of)';
   const LABEL = 'Label';
 
-  Polymer({
-    is: 'gr-access-section',
-
-    properties: {
-      capabilities: Object,
-      /** @type {?} */
-      section: {
-        type: Object,
-        notify: true,
-        observer: '_updateSection',
-      },
-      groups: Object,
-      labels: Object,
-      editing: {
-        type: Boolean,
-        value: false,
-        observer: '_handleEditingChanged',
-      },
-      canUpload: Boolean,
-      ownerOf: Array,
-      _originalId: String,
-      _editingRef: {
-        type: Boolean,
-        value: false,
-      },
-      _deleted: {
-        type: Boolean,
-        value: false,
-      },
-      _permissions: Array,
-    },
-
-    behaviors: [
-      Gerrit.AccessBehavior,
-      /**
+  /**
+    * @appliesMixin Gerrit.AccessMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrAccessSection extends Polymer.mixinBehaviors( [
+    Gerrit.AccessBehavior,
+    /**
        * Unused in this element, but called by other elements in tests
        * e.g gr-repo-access_test.
        */
-      Gerrit.FireBehavior,
-    ],
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-access-section'; }
 
-    listeners: {
-      'access-saved': '_handleAccessSaved',
-    },
+    static get properties() {
+      return {
+        capabilities: Object,
+        /** @type {?} */
+        section: {
+          type: Object,
+          notify: true,
+          observer: '_updateSection',
+        },
+        groups: Object,
+        labels: Object,
+        editing: {
+          type: Boolean,
+          value: false,
+          observer: '_handleEditingChanged',
+        },
+        canUpload: Boolean,
+        ownerOf: Array,
+        _originalId: String,
+        _editingRef: {
+          type: Boolean,
+          value: false,
+        },
+        _deleted: {
+          type: Boolean,
+          value: false,
+        },
+        _permissions: Array,
+      };
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('access-saved',
+          () => this._handleAccessSaved());
+    }
 
     _updateSection(section) {
       this._permissions = this.toSortedArray(section.value.permissions);
       this._originalId = section.id;
-    },
+    }
 
     _handleAccessSaved() {
       // Set a new 'original' value to keep track of after the value has been
       // saved.
       this._updateSection(this.section);
-    },
+    }
 
     _handleValueChange() {
       if (!this.section.value.added) {
@@ -103,7 +111,7 @@
             'access-modified', {bubbles: true, composed: true}));
       }
       this.section.value.updatedId = this.section.id;
-    },
+    }
 
     _handleEditingChanged(editing, editingOld) {
       // Ignore when editing gets set initially.
@@ -123,7 +131,7 @@
           }
         }
       }
-    },
+    }
 
     _computePermissions(name, capabilities, labels) {
       let allPermissions;
@@ -140,17 +148,17 @@
       return allPermissions.filter(permission => {
         return !this.section.value.permissions[permission.id];
       });
-    },
+    }
 
     _computeHideEditClass(section) {
       return section.id === 'GLOBAL_CAPABILITIES' ? 'hide' : '';
-    },
+    }
 
     _handleAddedPermissionRemoved(e) {
       const index = e.model.index;
       this._permissions = this._permissions.slice(0, index).concat(
           this._permissions.slice(index + 1, this._permissions.length));
-    },
+    }
 
     _computeLabelOptions(labels) {
       const labelOptions = [];
@@ -172,7 +180,7 @@
         });
       }
       return labelOptions;
-    },
+    }
 
     _computePermissionName(name, permission, permissionValues, capabilities) {
       if (name === GLOBAL_NAME) {
@@ -186,7 +194,7 @@
         }
         return `${LABEL} ${permission.value.label}${behalfOf}`;
       }
-    },
+    }
 
     _computeSectionName(name) {
       // When a new section is created, it doesn't yet have a ref. Set into
@@ -204,7 +212,7 @@
         return `Reference: ${name}`;
       }
       return name;
-    },
+    }
 
     _handleRemoveReference() {
       if (this.section.value.added) {
@@ -215,27 +223,27 @@
       this.section.value.deleted = true;
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _handleUndoRemove() {
       this._deleted = false;
       delete this.section.value.deleted;
-    },
+    }
 
     editRefInput() {
       return Polymer.dom(this.root).querySelector(Polymer.Element ?
-          'iron-input.editRefInput' :
-          'input[is=iron-input].editRefInput');
-    },
+        'iron-input.editRefInput' :
+        'input[is=iron-input].editRefInput');
+    }
 
     editReference() {
       this._editingRef = true;
       this.editRefInput().focus();
-    },
+    }
 
     _isEditEnabled(canUpload, ownerOf, sectionId) {
       return canUpload || (ownerOf && ownerOf.indexOf(sectionId) >= 0);
-    },
+    }
 
     _computeSectionClass(editing, canUpload, ownerOf, editingRef, deleted) {
       const classList = [];
@@ -249,11 +257,11 @@
         classList.push('deleted');
       }
       return classList.join(' ');
-    },
+    }
 
     _computeEditBtnClass(name) {
       return name === GLOBAL_NAME ? 'global' : '';
-    },
+    }
 
     _handleAddPermission() {
       const value = this.$.permissionSelect.value;
@@ -286,6 +294,8 @@
       this.push('_permissions', permission);
       this.set(['section.value.permissions', permission.id],
           permission.value);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccessSection.is, GrAccessSection);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section_test.html b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section_test.html
index 5110dc1..55b2495 100644
--- a/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-access-section/gr-access-section_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-access-section</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
@@ -188,7 +188,6 @@
         assert.isTrue(element.toSortedArray.lastCall.
             calledWithExactly(element.capabilities));
 
-
         // For everything else, include possible label values before filtering.
         name = 'refs/for/*';
         assert.deepEqual(element._computePermissions(name, element.capabilities,
@@ -206,8 +205,9 @@
           id: 'administrateServer',
           value: {},
         };
-        assert.equal(element._computePermissionName(name, permission,
-            element.permissionValues, element.capabilities),
+        assert.equal(
+            element._computePermissionName(name, permission,
+                element.permissionValues, element.capabilities),
             element.capabilities[permission.id].name);
 
         name = 'refs/for/*';
@@ -216,8 +216,9 @@
           value: {},
         };
 
-        assert.equal(element._computePermissionName(
-            name, permission, element.permissionValues, element.capabilities),
+        assert.equal(
+            element._computePermissionName(
+                name, permission, element.permissionValues, element.capabilities),
             element.permissionValues[permission.id].name);
 
         name = 'refs/for/*';
@@ -228,8 +229,9 @@
           },
         };
 
-        assert.equal(element._computePermissionName(name, permission,
-            element.permissionValues, element.capabilities),
+        assert.equal(
+            element._computePermissionName(name, permission,
+                element.permissionValues, element.capabilities),
             'Label Code-Review');
 
         permission = {
@@ -239,8 +241,9 @@
           },
         };
 
-        assert.equal(element._computePermissionName(name, permission,
-            element.permissionValues, element.capabilities),
+        assert.equal(
+            element._computePermissionName(name, permission,
+                element.permissionValues, element.capabilities),
             'Label Code-Review(On Behalf Of)');
       });
 
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.html b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.html
index bf1086c..5207717 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.html
+++ b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.html
@@ -30,8 +30,12 @@
 
 <dom-module id="gr-admin-group-list">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-table-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <gr-list-view
         create-new="[[_createNewCapability]]"
         filter="[[_filter]]"
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.js b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.js
index 4c099d6..e387724 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.js
+++ b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list.js
@@ -17,65 +17,72 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-admin-group-list',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.ListViewMixin
+    */
+  class GrAdminGroupList extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.ListViewBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-admin-group-list'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
 
-      /**
+        /**
        * Offset of currently visible query results.
        */
-      _offset: Number,
-      _path: {
-        type: String,
-        readOnly: true,
-        value: '/admin/groups',
-      },
-      _hasNewGroupName: Boolean,
-      _createNewCapability: {
-        type: Boolean,
-        value: false,
-      },
-      _groups: Array,
+        _offset: Number,
+        _path: {
+          type: String,
+          readOnly: true,
+          value: '/admin/groups',
+        },
+        _hasNewGroupName: Boolean,
+        _createNewCapability: {
+          type: Boolean,
+          value: false,
+        },
+        _groups: Array,
 
-      /**
+        /**
        * Because  we request one more than the groupsPerPage, _shownGroups
        * may be one less than _groups.
        * */
-      _shownGroups: {
-        type: Array,
-        computed: 'computeShownItems(_groups)',
-      },
+        _shownGroups: {
+          type: Array,
+          computed: 'computeShownItems(_groups)',
+        },
 
-      _groupsPerPage: {
-        type: Number,
-        value: 25,
-      },
+        _groupsPerPage: {
+          type: Number,
+          value: 25,
+        },
 
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _filter: String,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.ListViewBehavior,
-    ],
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _filter: String,
+      };
+    }
 
     attached() {
+      super.attached();
       this._getCreateGroupCapability();
       this.fire('title-change', {title: 'Groups'});
       this._maybeOpenCreateOverlay(this.params);
-    },
+    }
 
     _paramsChanged(params) {
       this._loading = true;
@@ -84,7 +91,7 @@
 
       return this._getGroups(this._filter, this._groupsPerPage,
           this._offset);
-    },
+    }
 
     /**
      * Opens the create overlay if the route has a hash 'create'
@@ -94,11 +101,11 @@
       if (params && params.openCreateModal) {
         this.$.createOverlay.open();
       }
-    },
+    }
 
     _computeGroupUrl(id) {
       return Gerrit.Nav.getUrlForGroup(id);
-    },
+    }
 
     _getCreateGroupCapability() {
       return this.$.restAPI.getAccount().then(account => {
@@ -110,7 +117,7 @@
               }
             });
       });
-    },
+    }
 
     _getGroups(filter, groupsPerPage, offset) {
       this._groups = [];
@@ -120,37 +127,39 @@
               return;
             }
             this._groups = Object.keys(groups)
-             .map(key => {
-               const group = groups[key];
-               group.name = key;
-               return group;
-             });
+                .map(key => {
+                  const group = groups[key];
+                  group.name = key;
+                  return group;
+                });
             this._loading = false;
           });
-    },
+    }
 
     _refreshGroupsList() {
       this.$.restAPI.invalidateGroupsCache();
       return this._getGroups(this._filter, this._groupsPerPage,
           this._offset);
-    },
+    }
 
     _handleCreateGroup() {
       this.$.createNewModal.handleCreateGroup().then(() => {
         this._refreshGroupsList();
       });
-    },
+    }
 
     _handleCloseCreate() {
       this.$.createOverlay.close();
-    },
+    }
 
     _handleCreateClicked() {
       this.$.createOverlay.open();
-    },
+    }
 
     _visibleToAll(item) {
       return item.options.visible_to_all === true ? 'Y' : 'N';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAdminGroupList.is, GrAdminGroupList);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list_test.html b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list_test.html
index 58c7be4..455b3a2 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-admin-group-list/gr-admin-group-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-admin-group-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.html b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.html
index c7187a9..aae11d3 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.html
+++ b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.html
@@ -43,8 +43,12 @@
 
 <dom-module id="gr-admin-view">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-menu-page-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-menu-page-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-page-nav-styles">
       gr-dropdown-list {
         --trigger-style: {
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.js b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.js
index d3f020d..23c7ae0 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.js
+++ b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view.js
@@ -17,66 +17,75 @@
 (function() {
   'use strict';
 
-
   const INTERNAL_GROUP_REGEX = /^[\da-f]{40}$/;
 
-  Polymer({
-    is: 'gr-admin-view',
+  /**
+    * @appliesMixin Gerrit.AdminNavMixin
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrAdminView extends Polymer.mixinBehaviors( [
+    Gerrit.AdminNavBehavior,
+    Gerrit.BaseUrlBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-admin-view'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      params: Object,
-      path: String,
-      adminView: String,
+        params: Object,
+        path: String,
+        adminView: String,
 
-      _breadcrumbParentName: String,
-      _repoName: String,
-      _groupId: {
-        type: Number,
-        observer: '_computeGroupName',
-      },
-      _groupIsInternal: Boolean,
-      _groupName: String,
-      _groupOwner: {
-        type: Boolean,
-        value: false,
-      },
-      _subsectionLinks: Array,
-      _filteredLinks: Array,
-      _showDownload: {
-        type: Boolean,
-        value: false,
-      },
-      _isAdmin: {
-        type: Boolean,
-        value: false,
-      },
-      _showGroup: Boolean,
-      _showGroupAuditLog: Boolean,
-      _showGroupList: Boolean,
-      _showGroupMembers: Boolean,
-      _showRepoAccess: Boolean,
-      _showRepoCommands: Boolean,
-      _showRepoDashboards: Boolean,
-      _showRepoDetailList: Boolean,
-      _showRepoMain: Boolean,
-      _showRepoList: Boolean,
-      _showPluginList: Boolean,
-    },
+        _breadcrumbParentName: String,
+        _repoName: String,
+        _groupId: {
+          type: Number,
+          observer: '_computeGroupName',
+        },
+        _groupIsInternal: Boolean,
+        _groupName: String,
+        _groupOwner: {
+          type: Boolean,
+          value: false,
+        },
+        _subsectionLinks: Array,
+        _filteredLinks: Array,
+        _showDownload: {
+          type: Boolean,
+          value: false,
+        },
+        _isAdmin: {
+          type: Boolean,
+          value: false,
+        },
+        _showGroup: Boolean,
+        _showGroupAuditLog: Boolean,
+        _showGroupList: Boolean,
+        _showGroupMembers: Boolean,
+        _showRepoAccess: Boolean,
+        _showRepoCommands: Boolean,
+        _showRepoDashboards: Boolean,
+        _showRepoDetailList: Boolean,
+        _showRepoMain: Boolean,
+        _showRepoList: Boolean,
+        _showPluginList: Boolean,
+      };
+    }
 
-    behaviors: [
-      Gerrit.AdminNavBehavior,
-      Gerrit.BaseUrlBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
-
-    observers: [
-      '_paramsChanged(params)',
-    ],
+    static get observers() {
+      return [
+        '_paramsChanged(params)',
+      ];
+    }
 
     attached() {
+      super.attached();
       this.reload();
-    },
+    }
 
     reload() {
       const promises = [
@@ -105,37 +114,37 @@
             .then(res => {
               this._filteredLinks = res.links;
               this._breadcrumbParentName = res.expandedSection ?
-                  res.expandedSection.name : '';
+                res.expandedSection.name : '';
 
               if (!res.expandedSection) {
                 this._subsectionLinks = [];
                 return;
               }
               this._subsectionLinks = [res.expandedSection]
-              .concat(res.expandedSection.children).map(section => {
-                return {
-                  text: !section.detailType ? 'Home' : section.name,
-                  value: section.view + (section.detailType || ''),
-                  view: section.view,
-                  url: section.url,
-                  detailType: section.detailType,
-                  parent: this._groupId || this._repoName || '',
-                };
-              });
+                  .concat(res.expandedSection.children).map(section => {
+                    return {
+                      text: !section.detailType ? 'Home' : section.name,
+                      value: section.view + (section.detailType || ''),
+                      view: section.view,
+                      url: section.url,
+                      detailType: section.detailType,
+                      parent: this._groupId || this._repoName || '',
+                    };
+                  });
             });
       });
-    },
+    }
 
     _computeSelectValue(params) {
       if (!params || !params.view) { return; }
       return params.view + (params.detail || '');
-    },
+    }
 
     _selectedIsCurrentPage(selected) {
       return (selected.parent === (this._repoName || this._groupId) &&
           selected.view === this.params.view &&
           selected.detailType === this.params.detail);
-    },
+    }
 
     _handleSubsectionChange(e) {
       const selected = this._subsectionLinks
@@ -146,7 +155,7 @@
         return;
       }
       Gerrit.Nav.navigateToRelativeUrl(selected.url);
-    },
+    }
 
     _paramsChanged(params) {
       const isGroupView = params.view === Gerrit.Nav.View.GROUP;
@@ -195,19 +204,19 @@
       }
       if (!needsReload) { return; }
       this.reload();
-    },
+    }
 
     // TODO (beckysiegel): Update these functions after router abstraction is
     // updated. They are currently copied from gr-dropdown (and should be
     // updated there as well once complete).
     _computeURLHelper(host, path) {
       return '//' + host + this.getBaseUrl() + path;
-    },
+    }
 
     _computeRelativeURL(path) {
       const host = window.location.host;
       return this._computeURLHelper(host, path);
-    },
+    }
 
     _computeLinkURL(link) {
       if (!link || typeof link.url === 'undefined') { return ''; }
@@ -215,7 +224,7 @@
         return link.url;
       }
       return this._computeRelativeURL(link.url);
-    },
+    }
 
     /**
      * @param {string} itemView
@@ -245,7 +254,7 @@
         return '';
       }
       return itemView === params.adminView ? 'selected' : '';
-    },
+    }
 
     _computeGroupName(groupId) {
       if (!groupId) { return ''; }
@@ -271,11 +280,13 @@
           this.reload();
         });
       });
-    },
+    }
 
     _updateGroupName(e) {
       this._groupName = e.detail.name;
       this.reload();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAdminView.is, GrAdminView);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view_test.html b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view_test.html
index 984be19..e6eef75 100644
--- a/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-admin-view/gr-admin-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-admin-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog.js b/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog.js
index acc76de..e257c71 100644
--- a/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog.js
+++ b/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog.js
@@ -23,9 +23,15 @@
     TAGS: 'tags',
   };
 
-  Polymer({
-    is: 'gr-confirm-delete-item-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmDeleteItemDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-delete-item-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -38,26 +44,24 @@
      * @event cancel
      */
 
-    properties: {
-      item: String,
-      itemType: String,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        item: String,
+        itemType: String,
+      };
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
+    }
 
     _computeItemName(detailType) {
       if (detailType === DETAIL_TYPES.BRANCHES) {
@@ -67,6 +71,9 @@
       } else if (detailType === DETAIL_TYPES.ID) {
         return 'ID';
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmDeleteItemDialog.is,
+      GrConfirmDeleteItemDialog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog_test.html b/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog_test.html
index 3292cec..c83349b 100644
--- a/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-confirm-delete-item-dialog/gr-confirm-delete-item-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-delete-item-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.html b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.html
index 2a95991..1d6e706 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.html
@@ -31,7 +31,9 @@
 
 <dom-module id="gr-create-change-dialog">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       input:not([type="checkbox"]),
       gr-autocomplete,
@@ -41,11 +43,6 @@
       .value {
         width: 32em;
       }
-      gr-autocomplete {
-        --gr-autocomplete: {
-          padding: 0 var(--spacing-xs);
-        }
-      }
       .hide {
         display: none;
       }
diff --git a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.js b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.js
index 5e4d102..31e2793 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.js
+++ b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog.js
@@ -20,44 +20,52 @@
   const SUGGESTIONS_LIMIT = 15;
   const REF_PREFIX = 'refs/heads/';
 
-  Polymer({
-    is: 'gr-create-change-dialog',
-
-    properties: {
-      repoName: String,
-      branch: String,
-      /** @type {?} */
-      _repoConfig: Object,
-      subject: String,
-      topic: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getRepoBranchesSuggestions.bind(this);
-        },
-      },
-      baseChange: String,
-      baseCommit: String,
-      privateByDefault: String,
-      canCreate: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
-      _privateChangesEnabled: Boolean,
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      /**
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrCreateChangeDialog extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    /**
        * Unused in this element, but called by other elements in tests
        * e.g gr-repo-commands_test.
        */
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-create-change-dialog'; }
+
+    static get properties() {
+      return {
+        repoName: String,
+        branch: String,
+        /** @type {?} */
+        _repoConfig: Object,
+        subject: String,
+        topic: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getRepoBranchesSuggestions.bind(this);
+          },
+        },
+        baseChange: String,
+        baseCommit: String,
+        privateByDefault: String,
+        canCreate: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
+        _privateChangesEnabled: Boolean,
+      };
+    }
 
     attached() {
+      super.attached();
       if (!this.repoName) { return Promise.resolve(); }
 
       const promises = [];
@@ -75,19 +83,21 @@
       }));
 
       return Promise.all(promises);
-    },
+    }
 
-    observers: [
-      '_allowCreate(branch, subject)',
-    ],
+    static get observers() {
+      return [
+        '_allowCreate(branch, subject)',
+      ];
+    }
 
     _computeBranchClass(baseChange) {
       return baseChange ? 'hide' : '';
-    },
+    }
 
     _allowCreate(branch, subject) {
       this.canCreate = !!branch && !!subject;
-    },
+    }
 
     handleCreateChange() {
       const isPrivate = this.$.privateChangeCheckBox.checked;
@@ -99,7 +109,7 @@
             if (!changeCreated) { return; }
             Gerrit.Nav.navigateToChange(changeCreated);
           });
-    },
+    }
 
     _getRepoBranchesSuggestions(input) {
       if (input.startsWith(REF_PREFIX)) {
@@ -107,22 +117,22 @@
       }
       return this.$.restAPI.getRepoBranches(
           input, this.repoName, SUGGESTIONS_LIMIT).then(response => {
-            const branches = [];
-            let branch;
-            for (const key in response) {
-              if (!response.hasOwnProperty(key)) { continue; }
-              if (response[key].ref.startsWith('refs/heads/')) {
-                branch = response[key].ref.substring('refs/heads/'.length);
-              } else {
-                branch = response[key].ref;
-              }
-              branches.push({
-                name: branch,
-              });
-            }
-            return branches;
+        const branches = [];
+        let branch;
+        for (const key in response) {
+          if (!response.hasOwnProperty(key)) { continue; }
+          if (response[key].ref.startsWith('refs/heads/')) {
+            branch = response[key].ref.substring('refs/heads/'.length);
+          } else {
+            branch = response[key].ref;
+          }
+          branches.push({
+            name: branch,
           });
-    },
+        }
+        return branches;
+      });
+    }
 
     _formatBooleanString(config) {
       if (config && config.configured_value === 'TRUE') {
@@ -138,10 +148,12 @@
       } else {
         return false;
       }
-    },
+    }
 
     _computePrivateSectionClass(config) {
       return config ? 'hide' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateChangeDialog.is, GrCreateChangeDialog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog_test.html b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog_test.html
index 3a3683f..3367aa3 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-change-dialog/gr-create-change-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-change-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.html b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.html
index 8a4287b..d0a1fca 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.html
@@ -26,7 +26,9 @@
 
 <dom-module id="gr-create-group-dialog">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       :host {
         display: inline-block;
diff --git a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.js b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.js
index 01aeb43..6b1af9a 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.js
+++ b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog.js
@@ -17,40 +17,48 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-create-group-dialog',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrCreateGroupDialog extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-create-group-dialog'; }
 
-    properties: {
-      params: Object,
-      hasNewGroupName: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
-      _name: Object,
-      _groupCreated: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        params: Object,
+        hasNewGroupName: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
+        _name: Object,
+        _groupCreated: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    observers: [
-      '_updateGroupName(_name)',
-    ],
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    static get observers() {
+      return [
+        '_updateGroupName(_name)',
+      ];
+    }
 
     _computeGroupUrl(groupId) {
       return this.getBaseUrl() + '/admin/groups/' +
           this.encodeURL(groupId, true);
-    },
+    }
 
     _updateGroupName(name) {
       this.hasNewGroupName = !!name;
-    },
+    }
 
     handleCreateGroup() {
       return this.$.restAPI.createGroup({name: this._name})
@@ -62,6 +70,8 @@
                   page.show(this._computeGroupUrl(group.group_id));
                 });
           });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateGroupDialog.is, GrCreateGroupDialog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog_test.html b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog_test.html
index ebca289..3a99526 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-group-dialog/gr-create-group-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-group-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
@@ -56,7 +56,8 @@
     test('name is updated correctly', done => {
       assert.isFalse(element.hasNewGroupName);
 
-      ironInput(element.root).bindValue = GROUP_NAME;
+      const inputEl = element.root.querySelector('iron-input');
+      inputEl.bindValue = GROUP_NAME;
 
       setTimeout(() => {
         assert.isTrue(element.hasNewGroupName);
diff --git a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.html b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.html
index ea5b84b..5a9213b 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.html
@@ -28,7 +28,9 @@
 
 <dom-module id="gr-create-pointer-dialog">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       :host {
         display: inline-block;
diff --git a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.js b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.js
index 4e9da90..56d7bc8 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.js
+++ b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog.js
@@ -22,35 +22,43 @@
     tags: 'tags',
   };
 
-  Polymer({
-    is: 'gr-create-pointer-dialog',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrCreatePointerDialog extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-create-pointer-dialog'; }
 
-    properties: {
-      detailType: String,
-      repoName: String,
-      hasNewItemName: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
-      itemDetail: String,
-      _itemName: String,
-      _itemRevision: String,
-      _itemAnnotation: String,
-    },
+    static get properties() {
+      return {
+        detailType: String,
+        repoName: String,
+        hasNewItemName: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
+        itemDetail: String,
+        _itemName: String,
+        _itemRevision: String,
+        _itemAnnotation: String,
+      };
+    }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
-
-    observers: [
-      '_updateItemName(_itemName)',
-    ],
+    static get observers() {
+      return [
+        '_updateItemName(_itemName)',
+      ];
+    }
 
     _updateItemName(name) {
       this.hasNewItemName = !!name;
-    },
+    }
 
     _computeItemUrl(project) {
       if (this.itemDetail === DETAIL_TYPES.branches) {
@@ -60,7 +68,7 @@
         return this.getBaseUrl() + '/admin/repos/' +
             this.encodeURL(this.repoName, true) + ',tags';
       }
-    },
+    }
 
     handleCreateItem() {
       const USE_HEAD = this._itemRevision ? this._itemRevision : 'HEAD';
@@ -82,10 +90,12 @@
               }
             });
       }
-    },
+    }
 
     _computeHideItemClass(type) {
       return type === DETAIL_TYPES.branches ? 'hideItem' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreatePointerDialog.is, GrCreatePointerDialog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog_test.html b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog_test.html
index 08e8213..41b8eca 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-pointer-dialog/gr-create-pointer-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-pointer-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -39,6 +39,10 @@
     let element;
     let sandbox;
 
+    const ironInput = function(element) {
+      return Polymer.dom(element).querySelector('iron-input');
+    };
+
     setup(() => {
       sandbox = sinon.sandbox.create();
       stub('gr-rest-api-interface', {
diff --git a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.html b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.html
index d1a2471..b78090c 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.html
@@ -29,7 +29,9 @@
 
 <dom-module id="gr-create-repo-dialog">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       :host {
         display: inline-block;
@@ -38,14 +40,7 @@
         width: 20em;
       }
       gr-autocomplete {
-        border: none;
-        --gr-autocomplete: {
-          border: 1px solid var(--border-color);
-          border-radius: var(--border-radius);
-          height: 2em;
-          padding: 0 var(--spacing-xs);
-          width: 20em;
-        }
+        width: 20em;
       }
     </style>
 
diff --git a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.js b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.js
index bb2b5f2..fd6dc4a 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.js
+++ b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog.js
@@ -17,69 +17,77 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-create-repo-dialog',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrCreateRepoDialog extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-create-repo-dialog'; }
 
-    properties: {
-      params: Object,
-      hasNewRepoName: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
+    static get properties() {
+      return {
+        params: Object,
+        hasNewRepoName: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
 
-      /** @type {?} */
-      _repoConfig: {
-        type: Object,
-        value: () => {
+        /** @type {?} */
+        _repoConfig: {
+          type: Object,
+          value: () => {
           // Set default values for dropdowns.
-          return {
-            create_empty_commit: true,
-            permissions_only: false,
-          };
+            return {
+              create_empty_commit: true,
+              permissions_only: false,
+            };
+          },
         },
-      },
-      _repoCreated: {
-        type: Boolean,
-        value: false,
-      },
-      _repoOwner: String,
-      _repoOwnerId: {
-        type: String,
-        observer: '_repoOwnerIdUpdate',
-      },
-
-      _query: {
-        type: Function,
-        value() {
-          return this._getRepoSuggestions.bind(this);
+        _repoCreated: {
+          type: Boolean,
+          value: false,
         },
-      },
-      _queryGroups: {
-        type: Function,
-        value() {
-          return this._getGroupSuggestions.bind(this);
+        _repoOwner: String,
+        _repoOwnerId: {
+          type: String,
+          observer: '_repoOwnerIdUpdate',
         },
-      },
-    },
 
-    observers: [
-      '_updateRepoName(_repoConfig.name)',
-    ],
+        _query: {
+          type: Function,
+          value() {
+            return this._getRepoSuggestions.bind(this);
+          },
+        },
+        _queryGroups: {
+          type: Function,
+          value() {
+            return this._getGroupSuggestions.bind(this);
+          },
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    static get observers() {
+      return [
+        '_updateRepoName(_repoConfig.name)',
+      ];
+    }
 
     _computeRepoUrl(repoName) {
       return this.getBaseUrl() + '/admin/repos/' +
           this.encodeURL(repoName, true);
-    },
+    }
 
     _updateRepoName(name) {
       this.hasNewRepoName = !!name;
-    },
+    }
 
     _repoOwnerIdUpdate(id) {
       if (id) {
@@ -87,7 +95,7 @@
       } else {
         this.set('_repoConfig.owners', undefined);
       }
-    },
+    }
 
     handleCreateRepo() {
       return this.$.restAPI.createRepo(this._repoConfig)
@@ -97,7 +105,7 @@
               page.show(this._computeRepoUrl(this._repoConfig.name));
             }
           });
-    },
+    }
 
     _getRepoSuggestions(input) {
       return this.$.restAPI.getSuggestedProjects(input)
@@ -112,7 +120,7 @@
             }
             return repos;
           });
-    },
+    }
 
     _getGroupSuggestions(input) {
       return this.$.restAPI.getSuggestedGroups(input)
@@ -127,6 +135,8 @@
             }
             return groups;
           });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateRepoDialog.is, GrCreateRepoDialog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog_test.html b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog_test.html
index 7e32c5c..fa481c2 100644
--- a/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-create-repo-dialog/gr-create-repo-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-repo-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.html b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.html
index c15f091..4ed751d 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.html
+++ b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.html
@@ -27,7 +27,9 @@
 
 <dom-module id="gr-group-audit-log">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-table-styles">
       /* GenericList style centers the last column, but we don't want that here. */
       .genericList tr th:last-of-type,
diff --git a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.js b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.js
index 8901d4a..e0c980c 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.js
+++ b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log.js
@@ -19,30 +19,38 @@
 
   const GROUP_EVENTS = ['ADD_GROUP', 'REMOVE_GROUP'];
 
-  Polymer({
-    is: 'gr-group-audit-log',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.ListViewMixin
+    */
+  class GrGroupAuditLog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.ListViewBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-group-audit-log'; }
 
-    properties: {
-      groupId: String,
-      _auditLog: Array,
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.ListViewBehavior,
-    ],
+    static get properties() {
+      return {
+        groupId: String,
+        _auditLog: Array,
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this.fire('title-change', {title: 'Audit Log'});
-    },
+    }
 
     ready() {
+      super.ready();
       this._getAuditLogs();
-    },
+    }
 
     _getAuditLogs() {
       if (!this.groupId) { return ''; }
@@ -60,11 +68,11 @@
             this._auditLog = auditLog;
             this._loading = false;
           });
-    },
+    }
 
     _status(item) {
       return item.disabled ? 'Disabled' : 'Enabled';
-    },
+    }
 
     itemType(type) {
       let item;
@@ -81,11 +89,11 @@
           item = '';
       }
       return item;
-    },
+    }
 
     _isGroupEvent(type) {
       return GROUP_EVENTS.indexOf(type) !== -1;
-    },
+    }
 
     _computeGroupUrl(group) {
       if (group && group.url && group.id) {
@@ -93,11 +101,11 @@
       }
 
       return '';
-    },
+    }
 
     _getIdForUser(account) {
       return account._account_id ? ' (' + account._account_id + ')' : '';
-    },
+    }
 
     _getNameForGroup(group) {
       if (group && group.name) {
@@ -108,6 +116,8 @@
       }
 
       return '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrGroupAuditLog.is, GrGroupAuditLog);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log_test.html b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log_test.html
index 313d465..d517242 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-group-audit-log/gr-group-audit-log_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-group-audit-log</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.html b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.html
index 86f66c4..cf24793 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.html
+++ b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.html
@@ -33,19 +33,21 @@
 
 <dom-module id="gr-group-members">
   <template>
-    <style include="gr-form-styles"></style>
-    <style include="gr-table-styles"></style>
-    <style include="gr-subpage-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-subpage-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       .input {
         width: 15em;
       }
       gr-autocomplete {
         width: 20em;
-        --gr-autocomplete: {
-          height: 2em;
-          width: 20em;
-        }
       }
       a {
         color: var(--primary-text-color);
diff --git a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.js b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.js
index 958c0ac..574bc29 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.js
+++ b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members.js
@@ -23,57 +23,65 @@
 
   const URL_REGEX = '^(?:[a-z]+:)?//';
 
-  Polymer({
-    is: 'gr-group-members',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrGroupMembers extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-group-members'; }
 
-    properties: {
-      groupId: Number,
-      _groupMemberSearchId: String,
-      _groupMemberSearchName: String,
-      _includedGroupSearchId: String,
-      _includedGroupSearchName: String,
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _groupName: String,
-      _groupMembers: Object,
-      _includedGroups: Object,
-      _itemName: String,
-      _itemType: String,
-      _queryMembers: {
-        type: Function,
-        value() {
-          return this._getAccountSuggestions.bind(this);
+    static get properties() {
+      return {
+        groupId: Number,
+        _groupMemberSearchId: String,
+        _groupMemberSearchName: String,
+        _includedGroupSearchId: String,
+        _includedGroupSearchName: String,
+        _loading: {
+          type: Boolean,
+          value: true,
         },
-      },
-      _queryIncludedGroup: {
-        type: Function,
-        value() {
-          return this._getGroupSuggestions.bind(this);
+        _groupName: String,
+        _groupMembers: Object,
+        _includedGroups: Object,
+        _itemName: String,
+        _itemType: String,
+        _queryMembers: {
+          type: Function,
+          value() {
+            return this._getAccountSuggestions.bind(this);
+          },
         },
-      },
-      _groupOwner: {
-        type: Boolean,
-        value: false,
-      },
-      _isAdmin: {
-        type: Boolean,
-        value: false,
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+        _queryIncludedGroup: {
+          type: Function,
+          value() {
+            return this._getGroupSuggestions.bind(this);
+          },
+        },
+        _groupOwner: {
+          type: Boolean,
+          value: false,
+        },
+        _isAdmin: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this._loadGroupDetails();
 
       this.fire('title-change', {title: 'Members'});
-    },
+    }
 
     _loadGroupDetails() {
       if (!this.groupId) { return; }
@@ -113,15 +121,15 @@
               this._loading = false;
             });
           });
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _isLoading() {
       return this._loading || this._loading === undefined;
-    },
+    }
 
     _computeGroupUrl(url) {
       if (!url) { return; }
@@ -136,21 +144,21 @@
         return this.getBaseUrl() + url.slice(1);
       }
       return this.getBaseUrl() + url;
-    },
+    }
 
     _handleSavingGroupMember() {
       return this.$.restAPI.saveGroupMembers(this._groupName,
           this._groupMemberSearchId).then(config => {
-            if (!config) {
-              return;
-            }
-            this.$.restAPI.getGroupMembers(this._groupName).then(members => {
-              this._groupMembers = members;
-            });
-            this._groupMemberSearchName = '';
-            this._groupMemberSearchId = '';
-          });
-    },
+        if (!config) {
+          return;
+        }
+        this.$.restAPI.getGroupMembers(this._groupName).then(members => {
+          this._groupMembers = members;
+        });
+        this._groupMemberSearchName = '';
+        this._groupMemberSearchId = '';
+      });
+    }
 
     _handleDeleteConfirm() {
       this.$.overlay.close();
@@ -177,11 +185,11 @@
               }
             });
       }
-    },
+    }
 
     _handleConfirmDialogCancel() {
       this.$.overlay.close();
-    },
+    }
 
     _handleDeleteMember(e) {
       const id = e.model.get('item._account_id');
@@ -196,7 +204,7 @@
       this._itemId = id;
       this._itemType = 'member';
       this.$.overlay.open();
-    },
+    }
 
     _handleSavingIncludedGroups() {
       return this.$.restAPI.saveIncludedGroup(this._groupName,
@@ -222,7 +230,7 @@
             this._includedGroupSearchName = '';
             this._includedGroupSearchId = '';
           });
-    },
+    }
 
     _handleDeleteIncludedGroup(e) {
       const id = decodeURIComponent(e.model.get('item.id')).replace(/\+/g, ' ');
@@ -233,31 +241,31 @@
       this._itemId = id;
       this._itemType = 'includedGroup';
       this.$.overlay.open();
-    },
+    }
 
     _getAccountSuggestions(input) {
       if (input.length === 0) { return Promise.resolve([]); }
       return this.$.restAPI.getSuggestedAccounts(
           input, SUGGESTIONS_LIMIT).then(accounts => {
-            const accountSuggestions = [];
-            let nameAndEmail;
-            if (!accounts) { return []; }
-            for (const key in accounts) {
-              if (!accounts.hasOwnProperty(key)) { continue; }
-              if (accounts[key].email !== undefined) {
-                nameAndEmail = accounts[key].name +
+        const accountSuggestions = [];
+        let nameAndEmail;
+        if (!accounts) { return []; }
+        for (const key in accounts) {
+          if (!accounts.hasOwnProperty(key)) { continue; }
+          if (accounts[key].email !== undefined) {
+            nameAndEmail = accounts[key].name +
                   ' <' + accounts[key].email + '>';
-              } else {
-                nameAndEmail = accounts[key].name;
-              }
-              accountSuggestions.push({
-                name: nameAndEmail,
-                value: accounts[key]._account_id,
-              });
-            }
-            return accountSuggestions;
+          } else {
+            nameAndEmail = accounts[key].name;
+          }
+          accountSuggestions.push({
+            name: nameAndEmail,
+            value: accounts[key]._account_id,
           });
-    },
+        }
+        return accountSuggestions;
+      });
+    }
 
     _getGroupSuggestions(input) {
       return this.$.restAPI.getSuggestedGroups(input)
@@ -272,10 +280,12 @@
             }
             return groups;
           });
-    },
+    }
 
     _computeHideItemClass(owner, admin) {
       return admin || owner ? '' : 'canModify';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrGroupMembers.is, GrGroupMembers);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members_test.html b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members_test.html
index 15a59c8..e90e6fd 100644
--- a/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-group-members/gr-group-members_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-group-members</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -169,10 +169,10 @@
           .querySelectorAll('.nameColumn a')[0].href, includedGroups[0].url);
       assert.equal(Polymer.dom(element.root)
           .querySelectorAll('.nameColumn a')[1].href,
-          'https://test/site/group/url');
+      'https://test/site/group/url');
       assert.equal(Polymer.dom(element.root)
           .querySelectorAll('.nameColumn a')[2].href,
-          'https://test/site/group/url');
+      'https://test/site/group/url');
     });
 
     test('save members correctly', () => {
diff --git a/polygerrit-ui/app/elements/admin/gr-group/gr-group.html b/polygerrit-ui/app/elements/admin/gr-group/gr-group.html
index 19879cb..faabe84 100644
--- a/polygerrit-ui/app/elements/admin/gr-group/gr-group.html
+++ b/polygerrit-ui/app/elements/admin/gr-group/gr-group.html
@@ -28,7 +28,9 @@
 
 <dom-module id="gr-group">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-subpage-styles">
       h3.edited:after {
         color: var(--deemphasized-text-color);
@@ -38,7 +40,9 @@
         margin-top: var(--spacing-s);
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <main class="gr-form-styles read-only">
       <div id="loading" class$="[[_computeLoadingClass(_loading)]]">
         Loading...
diff --git a/polygerrit-ui/app/elements/admin/gr-group/gr-group.js b/polygerrit-ui/app/elements/admin/gr-group/gr-group.js
index 68228b4..760ab9fa 100644
--- a/polygerrit-ui/app/elements/admin/gr-group/gr-group.js
+++ b/polygerrit-ui/app/elements/admin/gr-group/gr-group.js
@@ -30,78 +30,85 @@
     },
   };
 
-  Polymer({
-    is: 'gr-group',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrGroup extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-group'; }
     /**
      * Fired when the group name changes.
      *
      * @event name-changed
      */
 
-    properties: {
-      groupId: Number,
-      _rename: {
-        type: Boolean,
-        value: false,
-      },
-      _groupIsInternal: Boolean,
-      _description: {
-        type: Boolean,
-        value: false,
-      },
-      _owner: {
-        type: Boolean,
-        value: false,
-      },
-      _options: {
-        type: Boolean,
-        value: false,
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      /** @type {?} */
-      _groupConfig: Object,
-      _groupConfigOwner: String,
-      _groupName: Object,
-      _groupOwner: {
-        type: Boolean,
-        value: false,
-      },
-      _submitTypes: {
-        type: Array,
-        value() {
-          return Object.values(OPTIONS);
+    static get properties() {
+      return {
+        groupId: Number,
+        _rename: {
+          type: Boolean,
+          value: false,
         },
-      },
-      _query: {
-        type: Function,
-        value() {
-          return this._getGroupSuggestions.bind(this);
+        _groupIsInternal: Boolean,
+        _description: {
+          type: Boolean,
+          value: false,
         },
-      },
-      _isAdmin: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _owner: {
+          type: Boolean,
+          value: false,
+        },
+        _options: {
+          type: Boolean,
+          value: false,
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        /** @type {?} */
+        _groupConfig: Object,
+        _groupConfigOwner: String,
+        _groupName: Object,
+        _groupOwner: {
+          type: Boolean,
+          value: false,
+        },
+        _submitTypes: {
+          type: Array,
+          value() {
+            return Object.values(OPTIONS);
+          },
+        },
+        _query: {
+          type: Function,
+          value() {
+            return this._getGroupSuggestions.bind(this);
+          },
+        },
+        _isAdmin: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_handleConfigName(_groupConfig.name)',
-      '_handleConfigOwner(_groupConfig.owner, _groupConfigOwner)',
-      '_handleConfigDescription(_groupConfig.description)',
-      '_handleConfigOptions(_groupConfig.options.visible_to_all)',
-    ],
+    static get observers() {
+      return [
+        '_handleConfigName(_groupConfig.name)',
+        '_handleConfigOwner(_groupConfig.owner, _groupConfigOwner)',
+        '_handleConfigDescription(_groupConfig.description)',
+        '_handleConfigOptions(_groupConfig.options.visible_to_all)',
+      ];
+    }
 
     attached() {
+      super.attached();
       this._loadGroup();
-    },
+    }
 
     _loadGroup() {
       if (!this.groupId) { return; }
@@ -143,15 +150,15 @@
               this._loading = false;
             });
           });
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _isLoading() {
       return this._loading || this._loading === undefined;
-    },
+    }
 
     _handleSaveName() {
       return this.$.restAPI.saveGroupName(this.groupId, this._groupConfig.name)
@@ -163,7 +170,7 @@
               this._rename = false;
             }
           });
-    },
+    }
 
     _handleSaveOwner() {
       let owner = this._groupConfig.owner;
@@ -172,16 +179,16 @@
       }
       return this.$.restAPI.saveGroupOwner(this.groupId,
           owner).then(config => {
-            this._owner = false;
-          });
-    },
+        this._owner = false;
+      });
+    }
 
     _handleSaveDescription() {
       return this.$.restAPI.saveGroupDescription(this.groupId,
           this._groupConfig.description).then(config => {
-            this._description = false;
-          });
-    },
+        this._description = false;
+      });
+    }
 
     _handleSaveOptions() {
       const visible = this._groupConfig.options.visible_to_all;
@@ -190,33 +197,33 @@
 
       return this.$.restAPI.saveGroupOptions(this.groupId,
           options).then(config => {
-            this._options = false;
-          });
-    },
+        this._options = false;
+      });
+    }
 
     _handleConfigName() {
       if (this._isLoading()) { return; }
       this._rename = true;
-    },
+    }
 
     _handleConfigOwner() {
       if (this._isLoading()) { return; }
       this._owner = true;
-    },
+    }
 
     _handleConfigDescription() {
       if (this._isLoading()) { return; }
       this._description = true;
-    },
+    }
 
     _handleConfigOptions() {
       if (this._isLoading()) { return; }
       this._options = true;
-    },
+    }
 
     _computeHeaderClass(configChanged) {
       return configChanged ? 'edited' : '';
-    },
+    }
 
     _getGroupSuggestions(input) {
       return this.$.restAPI.getSuggestedGroups(input)
@@ -231,10 +238,12 @@
             }
             return groups;
           });
-    },
+    }
 
     _computeGroupDisabled(owner, admin, groupIsInternal) {
       return groupIsInternal && (admin || owner) ? false : true;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrGroup.is, GrGroup);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.html b/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.html
index 1672e85..0d7aae2 100644
--- a/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-group/gr-group_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-group</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.html b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.html
index 931e2cd..e07f911 100644
--- a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.html
+++ b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.html
@@ -82,8 +82,12 @@
         display: block;
       }
     </style>
-    <style include="gr-form-styles"></style>
-    <style include="gr-menu-page-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-menu-page-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <section
         id="permission"
         class$="gr-form-styles [[_computeSectionClass(editing, _deleted)]]">
diff --git a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.js b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.js
index b31aee6..e1e7c0a 100644
--- a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.js
+++ b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission.js
@@ -25,91 +25,100 @@
   ];
 
   /**
+    * @appliesMixin Gerrit.AccessMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  /**
    * Fired when the permission has been modified or removed.
    *
    * @event access-modified
    */
-
   /**
    * Fired when a permission that was previously added was removed.
    * @event added-permission-removed
    */
-
-  Polymer({
-    is: 'gr-permission',
-
-    properties: {
-      labels: Object,
-      name: String,
-      /** @type {?} */
-      permission: {
-        type: Object,
-        observer: '_sortPermission',
-        notify: true,
-      },
-      groups: Object,
-      section: String,
-      editing: {
-        type: Boolean,
-        value: false,
-        observer: '_handleEditingChanged',
-      },
-      _label: {
-        type: Object,
-        computed: '_computeLabel(permission, labels)',
-      },
-      _groupFilter: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getGroupSuggestions.bind(this);
-        },
-      },
-      _rules: Array,
-      _groupsWithRules: Object,
-      _deleted: {
-        type: Boolean,
-        value: false,
-      },
-      _originalExclusiveValue: Boolean,
-    },
-
-    behaviors: [
-      Gerrit.AccessBehavior,
-      /**
+  class GrPermission extends Polymer.mixinBehaviors( [
+    Gerrit.AccessBehavior,
+    /**
        * Unused in this element, but called by other elements in tests
        * e.g gr-access-section_test.
        */
-      Gerrit.FireBehavior,
-    ],
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-permission'; }
 
-    observers: [
-      '_handleRulesChanged(_rules.splices)',
-    ],
+    static get properties() {
+      return {
+        labels: Object,
+        name: String,
+        /** @type {?} */
+        permission: {
+          type: Object,
+          observer: '_sortPermission',
+          notify: true,
+        },
+        groups: Object,
+        section: String,
+        editing: {
+          type: Boolean,
+          value: false,
+          observer: '_handleEditingChanged',
+        },
+        _label: {
+          type: Object,
+          computed: '_computeLabel(permission, labels)',
+        },
+        _groupFilter: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getGroupSuggestions.bind(this);
+          },
+        },
+        _rules: Array,
+        _groupsWithRules: Object,
+        _deleted: {
+          type: Boolean,
+          value: false,
+        },
+        _originalExclusiveValue: Boolean,
+      };
+    }
 
-    listeners: {
-      'access-saved': '_handleAccessSaved',
-    },
+    static get observers() {
+      return [
+        '_handleRulesChanged(_rules.splices)',
+      ];
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('access-saved',
+          () => this._handleAccessSaved());
+    }
 
     ready() {
+      super.ready();
       this._setupValues();
-    },
+    }
 
     _setupValues() {
       if (!this.permission) { return; }
       this._originalExclusiveValue = !!this.permission.value.exclusive;
       Polymer.dom.flush();
-    },
+    }
 
     _handleAccessSaved() {
       // Set a new 'original' value to keep track of after the value has been
       // saved.
       this._setupValues();
-    },
+    }
 
     _permissionIsOwnerOrGlobal(permissionId, section) {
       return permissionId === 'owner' || section === 'GLOBAL_CAPABILITIES';
-    },
+    }
 
     _handleEditingChanged(editing, editingOld) {
       // Ignore when editing gets set initially.
@@ -130,20 +139,20 @@
         this.set(['permission', 'value', 'exclusive'],
             this._originalExclusiveValue);
       }
-    },
+    }
 
     _handleAddedRuleRemoved(e) {
       const index = e.model.index;
       this._rules = this._rules.slice(0, index)
           .concat(this._rules.slice(index + 1, this._rules.length));
-    },
+    }
 
     _handleValueChange() {
       this.permission.value.modified = true;
       // Allows overall access page to know a change has been made.
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _handleRemovePermission() {
       if (this.permission.value.added) {
@@ -154,16 +163,16 @@
       this.permission.value.deleted = true;
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _handleRulesChanged(changeRecord) {
       // Update the groups to exclude in the autocomplete.
       this._groupsWithRules = this._computeGroupsWithRules(this._rules);
-    },
+    }
 
     _sortPermission(permission) {
       this._rules = this.toSortedArray(permission.value.rules);
-    },
+    }
 
     _computeSectionClass(editing, deleted) {
       const classList = [];
@@ -174,12 +183,12 @@
         classList.push('deleted');
       }
       return classList.join(' ');
-    },
+    }
 
     _handleUndoRemove() {
       this._deleted = false;
       delete this.permission.value.deleted;
-    },
+    }
 
     _computeLabel(permission, labels) {
       if (!labels || !permission ||
@@ -195,7 +204,7 @@
         values: this._computeLabelValues(labels[labelName].values),
       };
       return label;
-    },
+    }
 
     _computeLabelValues(values) {
       const valuesArr = [];
@@ -211,7 +220,7 @@
         valuesArr.push({value: parseInt(key, 10), text});
       }
       return valuesArr;
-    },
+    }
 
     /**
      * @param {!Array} rules
@@ -224,12 +233,12 @@
         groups[rule.id] = true;
       }
       return groups;
-    },
+    }
 
     _computeGroupName(groups, groupId) {
       return groups && groups[groupId] && groups[groupId].name ?
-          groups[groupId].name : groupId;
-    },
+        groups[groupId].name : groupId;
+    }
 
     _getGroupSuggestions() {
       return this.$.restAPI.getSuggestedGroups(
@@ -249,7 +258,7 @@
               return !this._groupsWithRules[group.value.id];
             });
           });
-    },
+    }
 
     /**
      * Handles adding a skeleton item to the dom-repeat.
@@ -283,12 +292,14 @@
       this.set(['permission', 'value', 'rules', groupId], value);
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _computeHasRange(name) {
       if (!name) { return false; }
 
       return RANGE_NAMES.includes(name.toUpperCase());
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPermission.is, GrPermission);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission_test.html b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission_test.html
index 8e57534..6cb7e4a 100644
--- a/polygerrit-ui/app/elements/admin/gr-permission/gr-permission_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-permission/gr-permission_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-permission</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.html b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.html
index 2761526..f6c744b 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.html
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.html
@@ -25,7 +25,9 @@
 
 <dom-module id="gr-plugin-config-array-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       .wrapper {
         width: 30em;
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.js b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.js
index bb0d501..854bbbc 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.js
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor.js
@@ -17,39 +17,42 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-plugin-config-array-editor',
-
+  class GrPluginConfigArrayEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-plugin-config-array-editor'; }
     /**
      * Fired when the plugin config option changes.
      *
      * @event plugin-config-option-changed
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      pluginOption: Object,
-      /** @type {Boolean} */
-      disabled: {
-        type: Boolean,
-        computed: '_computeDisabled(pluginOption.*)',
-      },
-      /** @type {?} */
-      _newValue: {
-        type: String,
-        value: '',
-      },
-    },
+        pluginOption: Object,
+        /** @type {Boolean} */
+        disabled: {
+          type: Boolean,
+          computed: '_computeDisabled(pluginOption.*)',
+        },
+        /** @type {?} */
+        _newValue: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     _computeDisabled(record) {
       return !(record && record.base && record.base.info &&
           record.base.info.editable);
-    },
+    }
 
     _handleAddTap(e) {
       e.preventDefault();
       this._handleAdd();
-    },
+    }
 
     _handleInputKeydown(e) {
       // Enter.
@@ -57,20 +60,20 @@
         e.preventDefault();
         this._handleAdd();
       }
-    },
+    }
 
     _handleAdd() {
       if (!this._newValue.length) { return; }
       this._dispatchChanged(
           this.pluginOption.info.values.concat([this._newValue]));
       this._newValue = '';
-    },
+    }
 
     _handleDelete(e) {
       const value = Polymer.dom(e).localTarget.dataset.item;
       this._dispatchChanged(
           this.pluginOption.info.values.filter(str => str !== value));
-    },
+    }
 
     _dispatchChanged(values) {
       const {_key, info} = this.pluginOption;
@@ -81,10 +84,13 @@
       };
       this.dispatchEvent(
           new CustomEvent('plugin-config-option-changed', {detail}));
-    },
+    }
 
     _computeShowInputRow(disabled) {
       return disabled ? 'hide' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPluginConfigArrayEditor.is,
+      GrPluginConfigArrayEditor);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor_test.html b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor_test.html
index 39e4ddc..5198ad0 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-config-array-editor/gr-plugin-config-array-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-config-array-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.html b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.html
index 6ef84bf..b056f92 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.html
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.html
@@ -25,8 +25,12 @@
 
 <dom-module id="gr-plugin-list">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-table-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <gr-list-view
         filter="[[_filter]]"
         items-per-page="[[_pluginsPerPage]]"
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.js b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.js
index b77f078..e0089dc 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.js
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list.js
@@ -17,60 +17,67 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-plugin-list',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.ListViewMixin
+    */
+  class GrPluginList extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.ListViewBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-plugin-list'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
-      /**
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
+        /**
        * Offset of currently visible query results.
        */
-      _offset: {
-        type: Number,
-        value: 0,
-      },
-      _path: {
-        type: String,
-        readOnly: true,
-        value: '/admin/plugins',
-      },
-      _plugins: Array,
-      /**
+        _offset: {
+          type: Number,
+          value: 0,
+        },
+        _path: {
+          type: String,
+          readOnly: true,
+          value: '/admin/plugins',
+        },
+        _plugins: Array,
+        /**
        * Because  we request one more than the pluginsPerPage, _shownPlugins
        * maybe one less than _plugins.
        * */
-      _shownPlugins: {
-        type: Array,
-        computed: 'computeShownItems(_plugins)',
-      },
-      _pluginsPerPage: {
-        type: Number,
-        value: 25,
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _filter: {
-        type: String,
-        value: '',
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.ListViewBehavior,
-    ],
+        _shownPlugins: {
+          type: Array,
+          computed: 'computeShownItems(_plugins)',
+        },
+        _pluginsPerPage: {
+          type: Number,
+          value: 25,
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _filter: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this.fire('title-change', {title: 'Plugins'});
-    },
+    }
 
     _paramsChanged(params) {
       this._loading = true;
@@ -79,7 +86,7 @@
 
       return this._getPlugins(this._filter, this._pluginsPerPage,
           this._offset);
-    },
+    }
 
     _getPlugins(filter, pluginsPerPage, offset) {
       const errFn = response => {
@@ -92,21 +99,23 @@
               return;
             }
             this._plugins = Object.keys(plugins)
-             .map(key => {
-               const plugin = plugins[key];
-               plugin.name = key;
-               return plugin;
-             });
+                .map(key => {
+                  const plugin = plugins[key];
+                  plugin.name = key;
+                  return plugin;
+                });
             this._loading = false;
           });
-    },
+    }
 
     _status(item) {
       return item.disabled === true ? 'Disabled' : 'Enabled';
-    },
+    }
 
     _computePluginUrl(id) {
       return this.getUrl('/', id);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPluginList.is, GrPluginList);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list_test.html b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list_test.html
index 96fff60..98636a8 100644
--- a/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-plugin-list/gr-plugin-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.html b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.html
index ea12908..fab730d 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.html
@@ -33,7 +33,9 @@
 
 <dom-module id="gr-repo-access">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-subpage-styles">
       gr-button,
       #inheritsFrom,
@@ -68,7 +70,9 @@
         display: inline-block;
       }
     </style>
-    <style include="gr-menu-page-styles"></style>
+    <style include="gr-menu-page-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <main class$="[[_computeMainClass(_ownerOf, _canUpload, _editing)]]">
       <div id="loading" class$="[[_computeLoadingClass(_loading)]]">
         Loading...
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.js b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.js
index 94bef54..57a9183 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access.js
@@ -67,67 +67,77 @@
    */
   Defs.projectAccessInput;
 
+  /**
+    * @appliesMixin Gerrit.AccessMixin
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrRepoAccess extends Polymer.mixinBehaviors( [
+    Gerrit.AccessBehavior,
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-access'; }
 
-  Polymer({
-    is: 'gr-repo-access',
-
-    properties: {
-      repo: {
-        type: String,
-        observer: '_repoChanged',
-      },
-      // The current path
-      path: String,
-
-      _canUpload: {
-        type: Boolean,
-        value: false,
-      },
-      _inheritFromFilter: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getInheritFromSuggestions.bind(this);
+    static get properties() {
+      return {
+        repo: {
+          type: String,
+          observer: '_repoChanged',
         },
-      },
-      _ownerOf: Array,
-      _capabilities: Object,
-      _groups: Object,
-      /** @type {?} */
-      _inheritsFrom: Object,
-      _labels: Object,
-      _local: Object,
-      _editing: {
-        type: Boolean,
-        value: false,
-        observer: '_handleEditingChanged',
-      },
-      _modified: {
-        type: Boolean,
-        value: false,
-      },
-      _sections: Array,
-      _weblinks: Array,
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-    },
+        // The current path
+        path: String,
 
-    behaviors: [
-      Gerrit.AccessBehavior,
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+        _canUpload: {
+          type: Boolean,
+          value: false,
+        },
+        _inheritFromFilter: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getInheritFromSuggestions.bind(this);
+          },
+        },
+        _ownerOf: Array,
+        _capabilities: Object,
+        _groups: Object,
+        /** @type {?} */
+        _inheritsFrom: Object,
+        _labels: Object,
+        _local: Object,
+        _editing: {
+          type: Boolean,
+          value: false,
+          observer: '_handleEditingChanged',
+        },
+        _modified: {
+          type: Boolean,
+          value: false,
+        },
+        _sections: Array,
+        _weblinks: Array,
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+      };
+    }
 
-    listeners: {
-      'access-modified': '_handleAccessModified',
-    },
+    created() {
+      super.created();
+      this.addEventListener('access-modified',
+          () =>
+            this._handleAccessModified());
+    }
 
     _handleAccessModified() {
       this._modified = true;
-    },
+    }
 
     /**
      * @param {string} repo
@@ -139,7 +149,7 @@
       if (!repo) { return Promise.resolve(); }
 
       return this._reload(repo);
-    },
+    }
 
     _reload(repo) {
       const promises = [];
@@ -167,7 +177,7 @@
             // current value appears. If there is no parent repo, it is
             // initialized as an empty string.
             this._inheritFromFilter = res.inherits_from ?
-                this._inheritsFrom.name : '';
+              this._inheritsFrom.name : '';
             this._local = res.local;
             this._groups = res.groups;
             this._weblinks = res.config_web_links || [];
@@ -196,7 +206,7 @@
         this._sections = sections;
         this._loading = false;
       });
-    },
+    }
 
     _handleUpdateInheritFrom(e) {
       if (!this._inheritsFrom) {
@@ -205,7 +215,7 @@
       this._inheritsFrom.id = e.detail.value;
       this._inheritsFrom.name = this._inheritFromFilter;
       this._handleAccessModified();
-    },
+    }
 
     _getInheritFromSuggestions() {
       return this.$.restAPI.getRepos(
@@ -222,33 +232,33 @@
             }
             return projects;
           });
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _handleEdit() {
       this._editing = !this._editing;
-    },
+    }
 
     _editOrCancel(editing) {
       return editing ? 'Cancel' : 'Edit';
-    },
+    }
 
     _computeWebLinkClass(weblinks) {
       return weblinks && weblinks.length ? 'show' : '';
-    },
+    }
 
     _computeShowInherit(inheritsFrom) {
       return inheritsFrom ? 'show' : '';
-    },
+    }
 
     _handleAddedSectionRemoved(e) {
       const index = e.model.index;
       this._sections = this._sections.slice(0, index)
           .concat(this._sections.slice(index + 1, this._sections.length));
-    },
+    }
 
     _handleEditingChanged(editing, editingOld) {
       // Ignore when editing gets set initially.
@@ -267,7 +277,7 @@
           delete this._local[key];
         }
       }
-    },
+    }
 
     /**
      * @param {!Defs.projectAccessInput} addRemoveObj
@@ -297,7 +307,7 @@
         curPos = curPos[item];
       }
       return addRemoveObj;
-    },
+    }
 
     /**
      * Used to recursively remove any objects with a 'deleted' bit.
@@ -314,7 +324,7 @@
           this._recursivelyRemoveDeleted(obj[k]);
         }
       }
-    },
+    }
 
     _recursivelyUpdateAddRemoveObj(obj, addRemoveObj, path = []) {
       for (const k in obj) {
@@ -355,7 +365,7 @@
               path.concat(k));
         }
       }
-    },
+    }
 
     /**
      * Returns an object formatted for saving or submitting access changes for
@@ -370,11 +380,11 @@
       };
 
       const originalInheritsFromId = this._originalInheritsFrom ?
-          this.singleDecodeURL(this._originalInheritsFrom.id) :
-          null;
+        this.singleDecodeURL(this._originalInheritsFrom.id) :
+        null;
       const inheritsFromId = this._inheritsFrom ?
-          this.singleDecodeURL(this._inheritsFrom.id) :
-          null;
+        this.singleDecodeURL(this._inheritsFrom.id) :
+        null;
 
       const inheritFromChanged =
           // Inherit from changed
@@ -389,7 +399,7 @@
         addRemoveObj.parent = inheritsFromId;
       }
       return addRemoveObj;
-    },
+    }
 
     _handleCreateSection() {
       let newRef = 'refs/for/*';
@@ -404,7 +414,7 @@
       Polymer.dom.flush();
       Polymer.dom(this.root).querySelector('gr-access-section:last-of-type')
           .editReference();
-    },
+    }
 
     _getObjforSave() {
       const addRemoveObj = this._computeAddAndRemove();
@@ -427,7 +437,7 @@
         obj.parent = addRemoveObj.parent;
       }
       return obj;
-    },
+    }
 
     _handleSave() {
       const obj = this._getObjforSave();
@@ -436,7 +446,7 @@
           .then(() => {
             this._reload(this.repo);
           });
-    },
+    }
 
     _handleSaveForReview() {
       const obj = this._getObjforSave();
@@ -445,15 +455,15 @@
           .then(change => {
             Gerrit.Nav.navigateToChange(change);
           });
-    },
+    }
 
     _computeSaveReviewBtnClass(canUpload) {
       return !canUpload ? 'invisible' : '';
-    },
+    }
 
     _computeSaveBtnClass(ownerOf) {
       return ownerOf && ownerOf.length === 0 ? 'invisible' : '';
-    },
+    }
 
     _computeMainClass(ownerOf, canUpload, editing) {
       const classList = [];
@@ -464,11 +474,13 @@
         classList.push('editing');
       }
       return classList.join(' ');
-    },
+    }
 
     _computeParentHref(repoName) {
       return this.getBaseUrl() +
           `/admin/repos/${this.encodeURL(repoName, true)},access`;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoAccess.is, GrRepoAccess);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access_test.html b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access_test.html
index 8b1de6e..90eaba5 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-access/gr-repo-access_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-access</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
@@ -676,7 +676,7 @@
             Polymer.dom(element.$$('gr-access-section').root).querySelectorAll(
                 'gr-permission')[2];
         newPermission._handleAddRuleItem(
-           {detail: {value: {id: 'Maintainers'}}});
+            {detail: {value: {id: 'Maintainers'}}});
         assert.deepEqual(element._computeAddAndRemove(), expectedInput);
 
         // Modify a section reference.
@@ -909,7 +909,7 @@
             Polymer.dom(element.$$('gr-access-section').root).querySelectorAll(
                 'gr-permission')[1];
         readPermission._handleAddRuleItem(
-           {detail: {value: {id: 'Maintainers'}}});
+            {detail: {value: {id: 'Maintainers'}}});
 
         expectedInput = {
           add: {
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command.js b/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command.js
index 026c990..48e4c01 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command.js
@@ -17,14 +17,18 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-repo-command',
+  class GrRepoCommand extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-repo-command'; }
 
-    properties: {
-      title: String,
-      disabled: Boolean,
-      tooltip: String,
-    },
+    static get properties() {
+      return {
+        title: String,
+        disabled: Boolean,
+        tooltip: String,
+      };
+    }
 
     /**
      * Fired when command button is tapped.
@@ -35,6 +39,8 @@
     _onCommandTap() {
       this.dispatchEvent(
           new CustomEvent('command-tap', {bubbles: true, composed: true}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoCommand.is, GrRepoCommand);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command_test.html b/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command_test.html
index 49d8765..b8ec7e8 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-command/gr-repo-command_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-command</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.html b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.html
index 5089f34..b610460 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.html
@@ -31,9 +31,15 @@
 
 <dom-module id="gr-repo-commands">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-subpage-styles"></style>
-    <style include="gr-form-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-subpage-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <main class="gr-form-styles read-only">
       <h1 id="Title">Repository Commands</h1>
       <div id="loading" class$="[[_computeLoadingClass(_loading)]]">Loading...</div>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.js b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.js
index 92f15b0..f85af35 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands.js
@@ -26,30 +26,36 @@
   const CREATE_CHANGE_FAILED_MESSAGE = 'Failed to create change.';
   const CREATE_CHANGE_SUCCEEDED_MESSAGE = 'Navigating to change';
 
-  Polymer({
-    is: 'gr-repo-commands',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrRepoCommands extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-commands'; }
 
-    properties: {
-      params: Object,
-      repo: String,
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      /** @type {?} */
-      _repoConfig: Object,
-      _canCreate: Boolean,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        params: Object,
+        repo: String,
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        /** @type {?} */
+        _repoConfig: Object,
+        _canCreate: Boolean,
+      };
+    }
 
     attached() {
+      super.attached();
       this._loadRepo();
 
       this.fire('title-change', {title: 'Repo Commands'});
-    },
+    }
 
     _loadRepo() {
       if (!this.repo) { return Promise.resolve(); }
@@ -65,15 +71,15 @@
             this._repoConfig = config;
             this._loading = false;
           });
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _isLoading() {
       return this._loading || this._loading === undefined;
-    },
+    }
 
     _handleRunningGC() {
       return this.$.restAPI.runRepoGC(this.repo).then(response => {
@@ -83,35 +89,37 @@
               {detail: {message: GC_MESSAGE}, bubbles: true, composed: true}));
         }
       });
-    },
+    }
 
     _createNewChange() {
       this.$.createChangeOverlay.open();
-    },
+    }
 
     _handleCreateChange() {
       this.$.createNewChangeModal.handleCreateChange();
       this._handleCloseCreateChange();
-    },
+    }
 
     _handleCloseCreateChange() {
       this.$.createChangeOverlay.close();
-    },
+    }
 
     _handleEditRepoConfig() {
       return this.$.restAPI.createChange(this.repo, CONFIG_BRANCH,
           EDIT_CONFIG_SUBJECT, undefined, false, true).then(change => {
-            const message = change ?
-                CREATE_CHANGE_SUCCEEDED_MESSAGE :
-                CREATE_CHANGE_FAILED_MESSAGE;
-            this.dispatchEvent(new CustomEvent(
-                'show-alert',
-                {detail: {message}, bubbles: true, composed: true}));
-            if (!change) { return; }
+        const message = change ?
+          CREATE_CHANGE_SUCCEEDED_MESSAGE :
+          CREATE_CHANGE_FAILED_MESSAGE;
+        this.dispatchEvent(new CustomEvent(
+            'show-alert',
+            {detail: {message}, bubbles: true, composed: true}));
+        if (!change) { return; }
 
-            Gerrit.Nav.navigateToRelativeUrl(Gerrit.Nav.getEditUrlForDiff(
-                change, CONFIG_PATH, INITIAL_PATCHSET));
-          });
-    },
-  });
+        Gerrit.Nav.navigateToRelativeUrl(Gerrit.Nav.getEditUrlForDiff(
+            change, CONFIG_PATH, INITIAL_PATCHSET));
+      });
+    }
+  }
+
+  customElements.define(GrRepoCommands.is, GrRepoCommands);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands_test.html b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands_test.html
index 2976923..3c19175 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-commands/gr-repo-commands_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-commands</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.html b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.html
index 8af3a92..f74f705 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.html
@@ -35,7 +35,9 @@
         display: block;
       }
     </style>
-    <style include="gr-table-styles"></style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <table id="list" class$="genericList [[_computeLoadingClass(_loading)]]">
       <tr class="headerRow">
         <th class="topHeader">Dashboard name</th>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.js b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.js
index 6e38566..b4d34ae 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards.js
@@ -17,24 +17,29 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-repo-dashboards',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrRepoDashboards extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-dashboards'; }
 
-    properties: {
-      repo: {
-        type: String,
-        observer: '_repoChanged',
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _dashboards: Array,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        repo: {
+          type: String,
+          observer: '_repoChanged',
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _dashboards: Array,
+      };
+    }
 
     _repoChanged(repo) {
       this._loading = true;
@@ -49,7 +54,7 @@
 
         // Group by ref and sort by id.
         const dashboards = res.concat.apply([], res).sort((a, b) =>
-            a.id < b.id ? -1 : 1);
+          a.id < b.id ? -1 : 1);
         const dashboardsByRef = {};
         dashboards.forEach(d => {
           if (!dashboardsByRef[d.ref]) {
@@ -70,24 +75,26 @@
         this._loading = false;
         Polymer.dom.flush();
       });
-    },
+    }
 
     _getUrl(project, id) {
       if (!project || !id) { return ''; }
 
       return Gerrit.Nav.getUrlForRepoDashboard(project, id);
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _computeInheritedFrom(project, definingProject) {
       return project === definingProject ? '' : definingProject;
-    },
+    }
 
     _computeIsDefault(isDefault) {
       return isDefault ? '✓' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoDashboards.is, GrRepoDashboards);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards_test.html b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards_test.html
index 4f76983..06496de 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-dashboards/gr-repo-dashboards_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-dashboards</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.html b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.html
index 2f244f8..467cef0 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.html
@@ -35,8 +35,12 @@
 
 <dom-module id="gr-repo-detail-list">
   <template>
-    <style include="gr-form-styles"></style>
-    <style include="gr-table-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       .tags td.name {
         min-width: 25em;
@@ -81,7 +85,9 @@
         display: none;
       }
     </style>
-    <style include="gr-table-styles"></style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <gr-list-view
         create-new="[[_loggedIn]]"
         filter="[[_filter]]"
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.js b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.js
index da8ef52..bacc1e1 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list.js
@@ -24,75 +24,82 @@
 
   const PGP_START = '-----BEGIN PGP SIGNATURE-----';
 
-  Polymer({
-    is: 'gr-repo-detail-list',
+  /**
+    * @appliesMixin Gerrit.ListViewMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrRepoDetailList extends Polymer.mixinBehaviors( [
+    Gerrit.ListViewBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-detail-list'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
-      /**
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
+        /**
        * The kind of detail we are displaying, possibilities are determined by
        * the const DETAIL_TYPES.
        */
-      detailType: String,
+        detailType: String,
 
-      _editing: {
-        type: Boolean,
-        value: false,
-      },
-      _isOwner: {
-        type: Boolean,
-        value: false,
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-      /**
+        _editing: {
+          type: Boolean,
+          value: false,
+        },
+        _isOwner: {
+          type: Boolean,
+          value: false,
+        },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+        /**
        * Offset of currently visible query results.
        */
-      _offset: Number,
-      _repo: Object,
-      _items: Array,
-      /**
+        _offset: Number,
+        _repo: Object,
+        _items: Array,
+        /**
        * Because  we request one more than the projectsPerPage, _shownProjects
        * maybe one less than _projects.
        */
-      _shownItems: {
-        type: Array,
-        computed: 'computeShownItems(_items)',
-      },
-      _itemsPerPage: {
-        type: Number,
-        value: 25,
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _filter: String,
-      _refName: String,
-      _hasNewItemName: Boolean,
-      _isEditing: Boolean,
-      _revisedRef: String,
-    },
-
-    behaviors: [
-      Gerrit.ListViewBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+        _shownItems: {
+          type: Array,
+          computed: 'computeShownItems(_items)',
+        },
+        _itemsPerPage: {
+          type: Number,
+          value: 25,
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _filter: String,
+        _refName: String,
+        _hasNewItemName: Boolean,
+        _isEditing: Boolean,
+        _revisedRef: String,
+      };
+    }
 
     _determineIfOwner(repo) {
       return this.$.restAPI.getRepoAccess(repo)
           .then(access =>
-                this._isOwner = access && !!access[repo].is_owner);
-    },
+            this._isOwner = access && !!access[repo].is_owner);
+    }
 
     _paramsChanged(params) {
       if (!params || !params.repo) { return; }
@@ -113,7 +120,7 @@
 
       return this._getItems(this._filter, this._repo,
           this._itemsPerPage, this._offset, this.detailType);
-    },
+    }
 
     _getItems(filter, repo, itemsPerPage, offset, detailType) {
       this._loading = true;
@@ -125,36 +132,36 @@
       if (detailType === DETAIL_TYPES.BRANCHES) {
         return this.$.restAPI.getRepoBranches(
             filter, repo, itemsPerPage, offset, errFn).then(items => {
-              if (!items) { return; }
-              this._items = items;
-              this._loading = false;
-            });
+          if (!items) { return; }
+          this._items = items;
+          this._loading = false;
+        });
       } else if (detailType === DETAIL_TYPES.TAGS) {
         return this.$.restAPI.getRepoTags(
             filter, repo, itemsPerPage, offset, errFn).then(items => {
-              if (!items) { return; }
-              this._items = items;
-              this._loading = false;
-            });
+          if (!items) { return; }
+          this._items = items;
+          this._loading = false;
+        });
       }
-    },
+    }
 
     _getPath(repo) {
       return `/admin/repos/${this.encodeURL(repo, false)},` +
           `${this.detailType}`;
-    },
+    }
 
     _computeWeblink(repo) {
       if (!repo.web_links) { return ''; }
       const webLinks = repo.web_links;
       return webLinks.length ? webLinks : null;
-    },
+    }
 
     _computeMessage(message) {
       if (!message) { return; }
       // Strip PGP info.
       return message.split(PGP_START)[0];
-    },
+    }
 
     _stripRefs(item, detailType) {
       if (detailType === DETAIL_TYPES.BRANCHES) {
@@ -162,33 +169,33 @@
       } else if (detailType === DETAIL_TYPES.TAGS) {
         return item.replace('refs/tags/', '');
       }
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _computeEditingClass(isEditing) {
       return isEditing ? 'editing' : '';
-    },
+    }
 
     _computeCanEditClass(ref, detailType, isOwner) {
       return isOwner && this._stripRefs(ref, detailType) === 'HEAD' ?
-          'canEdit' : '';
-    },
+        'canEdit' : '';
+    }
 
     _handleEditRevision(e) {
       this._revisedRef = e.model.get('item.revision');
       this._isEditing = true;
-    },
+    }
 
     _handleCancelRevision() {
       this._isEditing = false;
-    },
+    }
 
     _handleSaveRevision(e) {
       this._setRepoHead(this._repo, this._revisedRef, e);
-    },
+    }
 
     _setRepoHead(repo, ref, e) {
       return this.$.restAPI.setRepoHead(repo, ref).then(res => {
@@ -202,7 +209,7 @@
               this._offset, this.detailType);
         }
       });
-    },
+    }
 
     _computeItemName(detailType) {
       if (detailType === DETAIL_TYPES.BRANCHES) {
@@ -210,7 +217,7 @@
       } else if (detailType === DETAIL_TYPES.TAGS) {
         return 'Tag';
       }
-    },
+    }
 
     _handleDeleteItemConfirm() {
       this.$.overlay.close();
@@ -233,18 +240,18 @@
               }
             });
       }
-    },
+    }
 
     _handleConfirmDialogCancel() {
       this.$.overlay.close();
-    },
+    }
 
     _handleDeleteItem(e) {
       const name = this._stripRefs(e.model.get('item.ref'), this.detailType);
       if (!name) { return; }
       this._refName = name;
       this.$.overlay.open();
-    },
+    }
 
     _computeHideDeleteClass(owner, canDelete) {
       if (canDelete || owner) {
@@ -252,20 +259,20 @@
       }
 
       return '';
-    },
+    }
 
     _handleCreateItem() {
       this.$.createNewModal.handleCreateItem();
       this._handleCloseCreate();
-    },
+    }
 
     _handleCloseCreate() {
       this.$.createOverlay.close();
-    },
+    }
 
     _handleCreateClicked() {
       this.$.createOverlay.open();
-    },
+    }
 
     _hideIfBranch(type) {
       if (type === DETAIL_TYPES.BRANCHES) {
@@ -273,10 +280,12 @@
       }
 
       return '';
-    },
+    }
 
     _computeHideTagger(tagger) {
       return tagger ? '' : 'hide';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoDetailList.is, GrRepoDetailList);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list_test.html b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list_test.html
index d8d4f7c..2b175c7 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-detail-list/gr-repo-detail-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-detail-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
@@ -155,9 +155,9 @@
         const cancelBtn = Polymer.dom(element.root).querySelector('.cancelBtn');
         const editBtn = Polymer.dom(element.root).querySelector('.editBtn');
         const revisionNoEditing = Polymer.dom(element.root)
-              .querySelector('.revisionNoEditing');
+            .querySelector('.revisionNoEditing');
         const revisionWithEditing = Polymer.dom(element.root)
-              .querySelector('.revisionWithEditing');
+            .querySelector('.revisionWithEditing');
 
         sandbox.stub(element, '_getLoggedIn').returns(Promise.resolve(true));
         sandbox.stub(element.$.restAPI, 'getRepoAccess').returns(
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.html b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.html
index 5e82c1e..08fd45c 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.html
@@ -27,8 +27,12 @@
 
 <dom-module id="gr-repo-list">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-table-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style>
       .genericList tr td:last-of-type {
         text-align: left;
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.js b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.js
index e0b054b..82bb3e2 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list.js
@@ -17,67 +17,73 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-repo-list',
+  /**
+    * @appliesMixin Gerrit.ListViewMixin
+    */
+  class GrRepoList extends Polymer.mixinBehaviors( [
+    Gerrit.ListViewBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-list'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
 
-      /**
+        /**
        * Offset of currently visible query results.
        */
-      _offset: Number,
-      _path: {
-        type: String,
-        readOnly: true,
-        value: '/admin/repos',
-      },
-      _hasNewRepoName: Boolean,
-      _createNewCapability: {
-        type: Boolean,
-        value: false,
-      },
-      _repos: Array,
+        _offset: Number,
+        _path: {
+          type: String,
+          readOnly: true,
+          value: '/admin/repos',
+        },
+        _hasNewRepoName: Boolean,
+        _createNewCapability: {
+          type: Boolean,
+          value: false,
+        },
+        _repos: Array,
 
-      /**
+        /**
        * Because  we request one more than the projectsPerPage, _shownProjects
        * maybe one less than _projects.
        * */
-      _shownRepos: {
-        type: Array,
-        computed: 'computeShownItems(_repos)',
-      },
+        _shownRepos: {
+          type: Array,
+          computed: 'computeShownItems(_repos)',
+        },
 
-      _reposPerPage: {
-        type: Number,
-        value: 25,
-      },
+        _reposPerPage: {
+          type: Number,
+          value: 25,
+        },
 
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _filter: {
-        type: String,
-        value: '',
-      },
-    },
-
-    behaviors: [
-      Gerrit.ListViewBehavior,
-    ],
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _filter: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this._getCreateRepoCapability();
       this.fire('title-change', {title: 'Repos'});
       this._maybeOpenCreateOverlay(this.params);
-    },
+    }
 
     _paramsChanged(params) {
       this._loading = true;
@@ -86,7 +92,7 @@
 
       return this._getRepos(this._filter, this._reposPerPage,
           this._offset);
-    },
+    }
 
     /**
      * Opens the create overlay if the route has a hash 'create'
@@ -96,15 +102,15 @@
       if (params && params.openCreateModal) {
         this.$.createOverlay.open();
       }
-    },
+    }
 
     _computeRepoUrl(name) {
       return this.getUrl(this._path + '/', name);
-    },
+    }
 
     _computeChangesLink(name) {
       return Gerrit.Nav.getUrlForProjectChanges(name);
-    },
+    }
 
     _getCreateRepoCapability() {
       return this.$.restAPI.getAccount().then(account => {
@@ -116,7 +122,7 @@
               }
             });
       });
-    },
+    }
 
     _getRepos(filter, reposPerPage, offset) {
       this._repos = [];
@@ -127,36 +133,38 @@
             this._repos = repos;
             this._loading = false;
           });
-    },
+    }
 
     _refreshReposList() {
       this.$.restAPI.invalidateReposCache();
       return this._getRepos(this._filter, this._reposPerPage,
           this._offset);
-    },
+    }
 
     _handleCreateRepo() {
       this.$.createNewModal.handleCreateRepo().then(() => {
         this._refreshReposList();
       });
-    },
+    }
 
     _handleCloseCreate() {
       this.$.createOverlay.close();
-    },
+    }
 
     _handleCreateClicked() {
       this.$.createOverlay.open();
-    },
+    }
 
     _readOnly(item) {
       return item.state === 'READ_ONLY' ? 'Y' : '';
-    },
+    }
 
     _computeWeblink(repo) {
       if (!repo.web_links) { return ''; }
       const webLinks = repo.web_links;
       return webLinks.length ? webLinks : null;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoList.is, GrRepoList);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list_test.html b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list_test.html
index c77592c..9569e56 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-list/gr-repo-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.html b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.html
index d2093e4..ef5b755 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.html
@@ -30,8 +30,12 @@
 
 <dom-module id="gr-repo-plugin-config">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-form-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-subpage-styles">
       .inherited {
         color: var(--deemphasized-text-color);
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.js b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.js
index 883a4e1..8658397 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config.js
@@ -17,28 +17,32 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-repo-plugin-config',
-
+  /**
+    * @appliesMixin Gerrit.RepoPluginConfigMixin
+    */
+  class GrRepoPluginConfig extends Polymer.mixinBehaviors( [
+    Gerrit.RepoPluginConfig,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-plugin-config'; }
     /**
      * Fired when the plugin config changes.
      *
      * @event plugin-config-changed
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      pluginData: Object,
-      /** @type {Array} */
-      _pluginConfigOptions: {
-        type: Array,
-        computed: '_computePluginConfigOptions(pluginData.*)',
-      },
-    },
-
-    behaviors: [
-      Gerrit.RepoPluginConfig,
-    ],
+        pluginData: Object,
+        /** @type {Array} */
+        _pluginConfigOptions: {
+          type: Array,
+          computed: '_computePluginConfigOptions(pluginData.*)',
+        },
+      };
+    }
 
     _computePluginConfigOptions(dataRecord) {
       if (!dataRecord || !dataRecord.base || !dataRecord.base.config) {
@@ -46,34 +50,34 @@
       }
       const {config} = dataRecord.base;
       return Object.keys(config).map(_key => ({_key, info: config[_key]}));
-    },
+    }
 
     _isArray(type) {
       return type === this.ENTRY_TYPES.ARRAY;
-    },
+    }
 
     _isBoolean(type) {
       return type === this.ENTRY_TYPES.BOOLEAN;
-    },
+    }
 
     _isList(type) {
       return type === this.ENTRY_TYPES.LIST;
-    },
+    }
 
     _isString(type) {
       // Treat numbers like strings for simplicity.
       return type === this.ENTRY_TYPES.STRING ||
           type === this.ENTRY_TYPES.INT ||
           type === this.ENTRY_TYPES.LONG;
-    },
+    }
 
     _computeDisabled(editable) {
       return editable === 'false';
-    },
+    }
 
     _computeChecked(value) {
       return JSON.parse(value);
-    },
+    }
 
     _handleStringChange(e) {
       const el = Polymer.dom(e).localTarget;
@@ -81,7 +85,7 @@
       const configChangeInfo =
           this._buildConfigChangeInfo(el.value, _key);
       this._handleChange(configChangeInfo);
-    },
+    }
 
     _handleListChange(e) {
       const el = Polymer.dom(e).localTarget;
@@ -89,7 +93,7 @@
       const configChangeInfo =
           this._buildConfigChangeInfo(el.value, _key);
       this._handleChange(configChangeInfo);
-    },
+    }
 
     _handleBooleanChange(e) {
       const el = Polymer.dom(e).localTarget;
@@ -97,7 +101,7 @@
       const configChangeInfo =
           this._buildConfigChangeInfo(JSON.stringify(el.checked), _key);
       this._handleChange(configChangeInfo);
-    },
+    }
 
     _buildConfigChangeInfo(value, _key) {
       const info = this.pluginData.config[_key];
@@ -107,11 +111,11 @@
         info,
         notifyPath: `${_key}.value`,
       };
-    },
+    }
 
     _handleArrayChange({detail}) {
       this._handleChange(detail);
-    },
+    }
 
     _handleChange({_key, info, notifyPath}) {
       const {name, config} = this.pluginData;
@@ -125,6 +129,8 @@
 
       this.dispatchEvent(new CustomEvent(
           this.PLUGIN_CONFIG_CHANGED, {detail, bubbles: true, composed: true}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoPluginConfig.is, GrRepoPluginConfig);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config_test.html b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config_test.html
index 07da7c7..ff0e522 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo-plugin-config/gr-repo-plugin-config_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-plugin-config</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -54,7 +54,7 @@
           {base: {config: {}}}), []);
       assert.deepEqual(element._computePluginConfigOptions(
           {base: {config: {testKey: 'testInfo'}}}),
-          [{_key: 'testKey', info: 'testInfo'}]);
+      [{_key: 'testKey', info: 'testInfo'}]);
     });
 
     test('_computeDisabled', () => {
diff --git a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.html b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.html
index 5de77b9..5e37261 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.html
@@ -32,7 +32,9 @@
 
 <dom-module id="gr-repo">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-subpage-styles">
       h2.edited:after {
         color: var(--deemphasized-text-color);
@@ -55,9 +57,13 @@
         display: block;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <main class="gr-form-styles read-only">
-      <style include="shared-styles"></style>
+      <style include="shared-styles">
+        /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+      </style>
       <div class="info">
         <h1 id="Title" class$="name">
           [[repo]]
diff --git a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.js b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.js
index 918efba..5bd7d27a 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.js
+++ b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo.js
@@ -51,76 +51,84 @@
     },
   };
 
-  Polymer({
-    is: 'gr-repo',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrRepo extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo'; }
 
-    properties: {
-      params: Object,
-      repo: String,
+    static get properties() {
+      return {
+        params: Object,
+        repo: String,
 
-      _configChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-        observer: '_loggedInChanged',
-      },
-      /** @type {?} */
-      _repoConfig: Object,
-      /** @type {?} */
-      _pluginData: {
-        type: Array,
-        computed: '_computePluginData(_repoConfig.plugin_config.*)',
-      },
-      _readOnly: {
-        type: Boolean,
-        value: true,
-      },
-      _states: {
-        type: Array,
-        value() {
-          return Object.values(STATES);
+        _configChanged: {
+          type: Boolean,
+          value: false,
         },
-      },
-      _submitTypes: {
-        type: Array,
-        value() {
-          return Object.values(SUBMIT_TYPES);
+        _loading: {
+          type: Boolean,
+          value: true,
         },
-      },
-      _schemes: {
-        type: Array,
-        value() { return []; },
-        computed: '_computeSchemes(_schemesObj)',
-        observer: '_schemesChanged',
-      },
-      _selectedCommand: {
-        type: String,
-        value: 'Clone',
-      },
-      _selectedScheme: String,
-      _schemesObj: Object,
-    },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+          observer: '_loggedInChanged',
+        },
+        /** @type {?} */
+        _repoConfig: Object,
+        /** @type {?} */
+        _pluginData: {
+          type: Array,
+          computed: '_computePluginData(_repoConfig.plugin_config.*)',
+        },
+        _readOnly: {
+          type: Boolean,
+          value: true,
+        },
+        _states: {
+          type: Array,
+          value() {
+            return Object.values(STATES);
+          },
+        },
+        _submitTypes: {
+          type: Array,
+          value() {
+            return Object.values(SUBMIT_TYPES);
+          },
+        },
+        _schemes: {
+          type: Array,
+          value() { return []; },
+          computed: '_computeSchemes(_schemesObj)',
+          observer: '_schemesChanged',
+        },
+        _selectedCommand: {
+          type: String,
+          value: 'Clone',
+        },
+        _selectedScheme: String,
+        _schemesObj: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_handleConfigChanged(_repoConfig.*)',
-    ],
+    static get observers() {
+      return [
+        '_handleConfigChanged(_repoConfig.*)',
+      ];
+    }
 
     attached() {
+      super.attached();
       this._loadRepo();
 
       this.fire('title-change', {title: this.repo});
-    },
+    }
 
     _computePluginData(configRecord) {
       if (!configRecord ||
@@ -129,7 +137,7 @@
       const pluginConfig = configRecord.base;
       return Object.keys(pluginConfig)
           .map(name => ({name, config: pluginConfig[name]}));
-    },
+    }
 
     _loadRepo() {
       if (!this.repo) { return Promise.resolve(); }
@@ -179,15 +187,15 @@
       }));
 
       return Promise.all(promises);
-    },
+    }
 
     _computeLoadingClass(loading) {
       return loading ? 'loading' : '';
-    },
+    }
 
     _computeHideClass(arr) {
       return !arr || !arr.length ? 'hide' : '';
-    },
+    }
 
     _loggedInChanged(_loggedIn) {
       if (!_loggedIn) { return; }
@@ -197,7 +205,7 @@
           this._selectedScheme = prefs.download_scheme.toLowerCase();
         }
       });
-    },
+    }
 
     _formatBooleanSelect(item) {
       if (!item) { return; }
@@ -218,7 +226,7 @@
           value: 'FALSE',
         },
       ];
-    },
+    }
 
     _formatSubmitTypeSelect(projectConfig) {
       if (!projectConfig) { return; }
@@ -248,15 +256,15 @@
         },
         ...allValues,
       ];
-    },
+    }
 
     _isLoading() {
       return this._loading || this._loading === undefined;
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _formatRepoConfigForSave(repoConfig) {
       const configInputObj = {};
@@ -278,38 +286,38 @@
         }
       }
       return configInputObj;
-    },
+    }
 
     _handleSaveRepoConfig() {
       return this.$.restAPI.saveRepoConfig(this.repo,
           this._formatRepoConfigForSave(this._repoConfig)).then(() => {
-            this._configChanged = false;
-          });
-    },
+        this._configChanged = false;
+      });
+    }
 
     _handleConfigChanged() {
       if (this._isLoading()) { return; }
       this._configChanged = true;
-    },
+    }
 
     _computeButtonDisabled(readOnly, configChanged) {
       return readOnly || !configChanged;
-    },
+    }
 
     _computeHeaderClass(configChanged) {
       return configChanged ? 'edited' : '';
-    },
+    }
 
     _computeSchemes(schemesObj) {
       return Object.keys(schemesObj);
-    },
+    }
 
     _schemesChanged(schemes) {
       if (schemes.length === 0) { return; }
       if (!schemes.includes(this._selectedScheme)) {
         this._selectedScheme = schemes.sort()[0];
       }
-    },
+    }
 
     _computeCommands(repo, schemesObj, _selectedScheme) {
       if (!schemesObj || !repo || !_selectedScheme) {
@@ -327,23 +335,25 @@
           command: commandObj[title]
               .replace(/\$\{project\}/gi, encodeURI(repo))
               .replace(/\$\{project-base-name\}/gi,
-              encodeURI(repo.substring(repo.lastIndexOf('/') + 1))),
+                  encodeURI(repo.substring(repo.lastIndexOf('/') + 1))),
         });
       }
       return commands;
-    },
+    }
 
     _computeRepositoriesClass(config) {
       return config ? 'showConfig': '';
-    },
+    }
 
     _computeChangesUrl(name) {
       return Gerrit.Nav.getUrlForProjectChanges(name);
-    },
+    }
 
     _handlePluginConfigChanged({detail: {name, config, notifyPath}}) {
       this._repoConfig.plugin_config[name] = config;
       this.notifyPath('_repoConfig.plugin_config.' + notifyPath);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepo.is, GrRepo);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo_test.html b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo_test.html
index f22c5a5..102a45e 100644
--- a/polygerrit-ui/app/elements/admin/gr-repo/gr-repo_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-repo/gr-repo_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -367,7 +367,7 @@
           element.$.matchAuthoredDateWithCommitterDateSelect.bindValue =
               configInputObj.match_author_to_committer_date;
           const inputElement = Polymer.Element ?
-              element.$.maxGitObjSizeIronInput : element.$.maxGitObjSizeInput;
+            element.$.maxGitObjSizeIronInput : element.$.maxGitObjSizeInput;
           inputElement.bindValue = configInputObj.max_object_size_limit;
           element.$.contributorAgreementSelect.bindValue =
               configInputObj.use_contributor_agreements;
diff --git a/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor.js b/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor.js
index df5a9f3..7c00787 100644
--- a/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor.js
+++ b/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor.js
@@ -63,62 +63,76 @@
     },
   ];
 
-  Polymer({
-    is: 'gr-rule-editor',
-
-    properties: {
-      hasRange: Boolean,
-      /** @type {?} */
-      label: Object,
-      editing: {
-        type: Boolean,
-        value: false,
-        observer: '_handleEditingChanged',
-      },
-      groupId: String,
-      groupName: String,
-      permission: String,
-      /** @type {?} */
-      rule: {
-        type: Object,
-        notify: true,
-      },
-      section: String,
-
-      _deleted: {
-        type: Boolean,
-        value: false,
-      },
-      _originalRuleValues: Object,
-    },
-
-    behaviors: [
-      Gerrit.AccessBehavior,
-      Gerrit.BaseUrlBehavior,
-      /**
+  /**
+    * @appliesMixin Gerrit.AccessMixin
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrRuleEditor extends Polymer.mixinBehaviors( [
+    Gerrit.AccessBehavior,
+    Gerrit.BaseUrlBehavior,
+    /**
        * Unused in this element, but called by other elements in tests
        * e.g gr-permission_test.
        */
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-rule-editor'; }
 
-    observers: [
-      '_handleValueChange(rule.value.*)',
-    ],
+    static get properties() {
+      return {
+        hasRange: Boolean,
+        /** @type {?} */
+        label: Object,
+        editing: {
+          type: Boolean,
+          value: false,
+          observer: '_handleEditingChanged',
+        },
+        groupId: String,
+        groupName: String,
+        permission: String,
+        /** @type {?} */
+        rule: {
+          type: Object,
+          notify: true,
+        },
+        section: String,
 
-    listeners: {
-      'access-saved': '_handleAccessSaved',
-    },
+        _deleted: {
+          type: Boolean,
+          value: false,
+        },
+        _originalRuleValues: Object,
+      };
+    }
+
+    static get observers() {
+      return [
+        '_handleValueChange(rule.value.*)',
+      ];
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('access-saved',
+          () => this._handleAccessSaved());
+    }
 
     ready() {
+      super.ready();
       // Called on ready rather than the observer because when new rules are
       // added, the observer is triggered prior to being ready.
       if (!this.rule) { return; } // Check needed for test purposes.
       this._setupValues(this.rule);
-    },
+    }
 
     attached() {
+      super.attached();
       if (!this.rule) { return; } // Check needed for test purposes.
       if (!this._originalRuleValues) {
         // Observer _handleValueChange is called after the ready()
@@ -126,13 +140,13 @@
         // avoid set .modified flag to true
         this._setOriginalRuleValues(this.rule.value);
       }
-    },
+    }
 
     _setupValues(rule) {
       if (!rule.value) {
         this._setDefaultRuleValues();
       }
-    },
+    }
 
     _computeForce(permission, action) {
       if (this.permissionValues.push.id === permission &&
@@ -141,21 +155,21 @@
       }
 
       return this.permissionValues.editTopicName.id === permission;
-    },
+    }
 
     _computeForceClass(permission, action) {
       return this._computeForce(permission, action) ? 'force' : '';
-    },
+    }
 
     _computeGroupPath(group) {
       return `${this.getBaseUrl()}/admin/groups/${this.encodeURL(group, true)}`;
-    },
+    }
 
     _handleAccessSaved() {
       // Set a new 'original' value to keep track of after the value has been
       // saved.
       this._setOriginalRuleValues(this.rule.value);
-    },
+    }
 
     _handleEditingChanged(editing, editingOld) {
       // Ignore when editing gets set initially.
@@ -164,7 +178,7 @@
       if (!editing) {
         this._handleUndoChange();
       }
-    },
+    }
 
     _computeSectionClass(editing, deleted) {
       const classList = [];
@@ -175,7 +189,7 @@
         classList.push('deleted');
       }
       return classList.join(' ');
-    },
+    }
 
     _computeForceOptions(permission, action) {
       if (permission === this.permissionValues.push.id) {
@@ -190,7 +204,7 @@
         return FORCE_EDIT_OPTIONS;
       }
       return [];
-    },
+    }
 
     _getDefaultRuleValues(permission, label) {
       const ruleAction = Action.ALLOW;
@@ -207,19 +221,19 @@
       }
       value.action = DROPDOWN_OPTIONS[0];
       return value;
-    },
+    }
 
     _setDefaultRuleValues() {
       this.set('rule.value', this._getDefaultRuleValues(this.permission,
           this.label));
-    },
+    }
 
     _computeOptions(permission) {
       if (permission === 'priority') {
         return PRIORITY_OPTIONS;
       }
       return DROPDOWN_OPTIONS;
-    },
+    }
 
     _handleRemoveRule() {
       if (this.rule.value.added) {
@@ -230,12 +244,12 @@
       this.rule.value.deleted = true;
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _handleUndoRemove() {
       this._deleted = false;
       delete this.rule.value.deleted;
-    },
+    }
 
     _handleUndoChange() {
       // gr-permission will take care of removing rules that were added but
@@ -245,7 +259,7 @@
       this._deleted = false;
       delete this.rule.value.deleted;
       delete this.rule.value.modified;
-    },
+    }
 
     _handleValueChange() {
       if (!this._originalRuleValues) { return; }
@@ -253,10 +267,12 @@
       // Allows overall access page to know a change has been made.
       this.dispatchEvent(
           new CustomEvent('access-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _setOriginalRuleValues(value) {
       this._originalRuleValues = Object.assign({}, value);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRuleEditor.is, GrRuleEditor);
 })();
diff --git a/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor_test.html b/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor_test.html
index 4ea3817..dbf5bb0 100644
--- a/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor_test.html
+++ b/polygerrit-ui/app/elements/admin/gr-rule-editor/gr-rule-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-rule-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
@@ -125,7 +125,7 @@
         let permission = 'priority';
         let label;
         assert.deepEqual(element._getDefaultRuleValues(permission, label),
-          {action: 'BATCH'});
+            {action: 'BATCH'});
         permission = 'label-Code-Review';
         label = {values: [
           {value: -2, text: 'This shall not be merged'},
@@ -139,7 +139,7 @@
         permission = 'push';
         label = undefined;
         assert.deepEqual(element._getDefaultRuleValues(permission, label),
-          {action: 'ALLOW', force: false});
+            {action: 'ALLOW', force: false});
         permission = 'submit';
         assert.deepEqual(element._getDefaultRuleValues(permission, label),
             {action: 'ALLOW'});
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.html b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.html
index a6c86bb..f1338fb 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.html
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.html
@@ -124,7 +124,9 @@
         }
       }
     </style>
-    <style include="gr-change-list-styles"></style>
+    <style include="gr-change-list-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <td class="cell leftPadding"></td>
     <td class="cell star" hidden$="[[!showStar]]" hidden>
       <gr-change-star change="{{change}}"></gr-change-star>
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.js b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.js
index 8eb39891..3ce87f8 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.js
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item.js
@@ -24,57 +24,67 @@
     LARGE: 1000,
   };
 
-  Polymer({
-    is: 'gr-change-list-item',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.ChangeTableMixin
+    * @appliesMixin Gerrit.PathListMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrChangeListItem extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.ChangeTableBehavior,
+    Gerrit.PathListBehavior,
+    Gerrit.RESTClientBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-list-item'; }
 
-    properties: {
-      visibleChangeTableColumns: Array,
-      labelNames: {
-        type: Array,
-      },
+    static get properties() {
+      return {
+        visibleChangeTableColumns: Array,
+        labelNames: {
+          type: Array,
+        },
 
-      /** @type {?} */
-      change: Object,
-      changeURL: {
-        type: String,
-        computed: '_computeChangeURL(change)',
-      },
-      statuses: {
-        type: Array,
-        computed: 'changeStatuses(change)',
-      },
-      showStar: {
-        type: Boolean,
-        value: false,
-      },
-      showNumber: Boolean,
-      _changeSize: {
-        type: String,
-        computed: '_computeChangeSize(change)',
-      },
-      _dynamicCellEndpoints: {
-        type: Array,
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.ChangeTableBehavior,
-      Gerrit.PathListBehavior,
-      Gerrit.RESTClientBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+        /** @type {?} */
+        change: Object,
+        changeURL: {
+          type: String,
+          computed: '_computeChangeURL(change)',
+        },
+        statuses: {
+          type: Array,
+          computed: 'changeStatuses(change)',
+        },
+        showStar: {
+          type: Boolean,
+          value: false,
+        },
+        showNumber: Boolean,
+        _changeSize: {
+          type: String,
+          computed: '_computeChangeSize(change)',
+        },
+        _dynamicCellEndpoints: {
+          type: Array,
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       Gerrit.awaitPluginsLoaded().then(() => {
         this._dynamicCellEndpoints = Gerrit._endpoints.getDynamicEndpoints(
             'change-list-item-cell');
       });
-    },
+    }
 
     _computeChangeURL(change) {
       return Gerrit.Nav.getUrlForChange(change);
-    },
+    }
 
     _computeLabelTitle(change, labelName) {
       const label = change.labels[labelName];
@@ -85,7 +95,7 @@
         return labelName + '\nby ' + significantLabel.name;
       }
       return labelName;
-    },
+    }
 
     _computeLabelClass(change, labelName) {
       const label = change.labels[labelName];
@@ -112,7 +122,7 @@
         classes['u-gray-background'] = true;
       }
       return Object.keys(classes).sort().join(' ');
-    },
+    }
 
     _computeLabelValue(change, labelName) {
       const label = change.labels[labelName];
@@ -130,22 +140,22 @@
         return label.value;
       }
       return '';
-    },
+    }
 
     _computeRepoUrl(change) {
       return Gerrit.Nav.getUrlForProjectChanges(change.project, true,
           change.internalHost);
-    },
+    }
 
     _computeRepoBranchURL(change) {
       return Gerrit.Nav.getUrlForBranch(change.branch, change.project, null,
           change.internalHost);
-    },
+    }
 
     _computeTopicURL(change) {
       if (!change.topic) { return ''; }
       return Gerrit.Nav.getUrlForTopic(change.topic, change.internalHost);
-    },
+    }
 
     /**
      * Computes the display string for the project column. If there is a host
@@ -162,7 +172,7 @@
       if (change.internalHost) { str += change.internalHost + '/'; }
       str += truncate ? this.truncatePath(change.project, 2) : change.project;
       return str;
-    },
+    }
 
     _computeSizeTooltip(change) {
       if (change.insertions + change.deletions === 0 ||
@@ -171,7 +181,7 @@
       } else {
         return `+${change.insertions}, -${change.deletions}`;
       }
-    },
+    }
 
     /**
      * TShirt sizing is based on the following paper:
@@ -193,7 +203,7 @@
       } else {
         return 'XL';
       }
-    },
+    }
 
     toggleReviewed() {
       const newVal = !this.change.reviewed;
@@ -203,6 +213,8 @@
         composed: true,
         detail: {change: this.change, reviewed: newVal},
       }));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeListItem.is, GrChangeListItem);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item_test.html b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item_test.html
index 1cddbc5..3c402d1 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-item/gr-change-list-item_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-list-item</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -57,33 +57,34 @@
           'cell label u-gray-background');
       assert.equal(element._computeLabelClass(
           {labels: {}}, 'Verified'), 'cell label u-gray-background');
-      assert.equal(element._computeLabelClass(
-          {labels: {Verified: {approved: true, value: 1}}}, 'Verified'),
+      assert.equal(
+          element._computeLabelClass(
+              {labels: {Verified: {approved: true, value: 1}}}, 'Verified'),
           'cell label u-green u-monospace');
       assert.equal(element._computeLabelClass(
           {labels: {Verified: {rejected: true, value: -1}}}, 'Verified'),
-          'cell label u-monospace u-red');
+      'cell label u-monospace u-red');
       assert.equal(element._computeLabelClass(
           {labels: {'Code-Review': {value: 1}}}, 'Code-Review'),
-          'cell label u-green u-monospace');
+      'cell label u-green u-monospace');
       assert.equal(element._computeLabelClass(
           {labels: {'Code-Review': {value: -1}}}, 'Code-Review'),
-          'cell label u-monospace u-red');
+      'cell label u-monospace u-red');
       assert.equal(element._computeLabelClass(
           {labels: {'Code-Review': {value: -1}}}, 'Verified'),
-          'cell label u-gray-background');
+      'cell label u-gray-background');
 
       assert.equal(element._computeLabelTitle({labels: {}}, 'Verified'),
           'Label not applicable');
       assert.equal(element._computeLabelTitle(
           {labels: {Verified: {approved: {name: 'Diffy'}}}}, 'Verified'),
-          'Verified\nby Diffy');
+      'Verified\nby Diffy');
       assert.equal(element._computeLabelTitle(
           {labels: {Verified: {approved: {name: 'Diffy'}}}}, 'Code-Review'),
-          'Label not applicable');
+      'Label not applicable');
       assert.equal(element._computeLabelTitle(
           {labels: {Verified: {rejected: {name: 'Diffy'}}}}, 'Verified'),
-          'Verified\nby Diffy');
+      'Verified\nby Diffy');
       assert.equal(element._computeLabelTitle(
           {labels: {'Code-Review': {disliked: {name: 'Diffy'}, value: -1}}},
           'Code-Review'), 'Code-Review\nby Diffy');
@@ -93,19 +94,19 @@
       assert.equal(element._computeLabelTitle(
           {labels: {'Code-Review': {recommended: {name: 'Diffy'},
             rejected: {name: 'Admin'}}}}, 'Code-Review'),
-          'Code-Review\nby Admin');
+      'Code-Review\nby Admin');
       assert.equal(element._computeLabelTitle(
           {labels: {'Code-Review': {approved: {name: 'Diffy'},
             rejected: {name: 'Admin'}}}}, 'Code-Review'),
-          'Code-Review\nby Admin');
+      'Code-Review\nby Admin');
       assert.equal(element._computeLabelTitle(
           {labels: {'Code-Review': {recommended: {name: 'Diffy'},
             disliked: {name: 'Admin'}, value: -1}}}, 'Code-Review'),
-          'Code-Review\nby Admin');
+      'Code-Review\nby Admin');
       assert.equal(element._computeLabelTitle(
           {labels: {'Code-Review': {approved: {name: 'Diffy'},
             disliked: {name: 'Admin'}, value: -1}}}, 'Code-Review'),
-          'Code-Review\nby Diffy');
+      'Code-Review\nby Diffy');
 
       assert.equal(element._computeLabelValue({labels: {}}), '');
       assert.equal(element._computeLabelValue({labels: {}}, 'Verified'), '');
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.js b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.js
index 02e9a04..49aa1eb 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.js
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.js
@@ -29,44 +29,49 @@
 
   const LIMIT_OPERATOR_PATTERN = /\blimit:(\d+)/i;
 
-  Polymer({
-    is: 'gr-change-list-view',
-
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrChangeListView extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-list-view'; }
     /**
      * Fired when the title of the page should change.
      *
      * @event title-change
      */
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
-
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
 
-      /**
+        /**
        * True when user is logged in.
        */
-      _loggedIn: {
-        type: Boolean,
-        computed: '_computeLoggedIn(account)',
-      },
+        _loggedIn: {
+          type: Boolean,
+          computed: '_computeLoggedIn(account)',
+        },
 
-      account: {
-        type: Object,
-        value: null,
-      },
+        account: {
+          type: Object,
+          value: null,
+        },
 
-      /**
+        /**
        * State persisted across restamps of the element.
        *
        * Need sub-property declaration since it is used in template before
@@ -74,66 +79,71 @@
        * @type {{ selectedChangeIndex: (number|undefined) }}
        *
        */
-      viewState: {
-        type: Object,
-        notify: true,
-        value() { return {}; },
-      },
+        viewState: {
+          type: Object,
+          notify: true,
+          value() { return {}; },
+        },
 
-      preferences: Object,
+        preferences: Object,
 
-      _changesPerPage: Number,
+        _changesPerPage: Number,
 
-      /**
+        /**
        * Currently active query.
        */
-      _query: {
-        type: String,
-        value: '',
-      },
+        _query: {
+          type: String,
+          value: '',
+        },
 
-      /**
+        /**
        * Offset of currently visible query results.
        */
-      _offset: Number,
+        _offset: Number,
 
-      /**
+        /**
        * Change objects loaded from the server.
        */
-      _changes: {
-        type: Array,
-        observer: '_changesChanged',
-      },
+        _changes: {
+          type: Array,
+          observer: '_changesChanged',
+        },
 
-      /**
+        /**
        * For showing a "loading..." string during ajax requests.
        */
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
 
-      /** @type {?String} */
-      _userId: {
-        type: String,
-        value: null,
-      },
+        /** @type {?String} */
+        _userId: {
+          type: String,
+          value: null,
+        },
 
-      /** @type {?String} */
-      _repo: {
-        type: String,
-        value: null,
-      },
-    },
+        /** @type {?String} */
+        _repo: {
+          type: String,
+          value: null,
+        },
+      };
+    }
 
-    listeners: {
-      'next-page': '_handleNextPage',
-      'previous-page': '_handlePreviousPage',
-    },
+    created() {
+      super.created();
+      this.addEventListener('next-page',
+          () => this._handleNextPage());
+      this.addEventListener('previous-page',
+          () => this._handlePreviousPage());
+    }
 
     attached() {
+      super.attached();
       this._loadPreferences();
-    },
+    }
 
     _paramsChanged(value) {
       if (value.view !== Gerrit.Nav.View.SEARCH) { return; }
@@ -170,7 +180,7 @@
         this._changes = changes;
         this._loading = false;
       });
-    },
+    }
 
     _loadPreferences() {
       return this.$.restAPI.getLoggedIn().then(loggedIn => {
@@ -182,20 +192,20 @@
           this.preferences = {};
         }
       });
-    },
+    }
 
     _replaceCurrentLocation(url) {
       window.location.replace(url);
-    },
+    }
 
     _getChanges() {
       return this.$.restAPI.getChanges(this._changesPerPage, this._query,
           this._offset);
-    },
+    }
 
     _getPreferences() {
       return this.$.restAPI.getPreferences();
-    },
+    }
 
     _limitFor(query, defaultLimit) {
       const match = query.match(LIMIT_OPERATOR_PATTERN);
@@ -203,7 +213,7 @@
         return defaultLimit;
       }
       return parseInt(match[1], 10);
-    },
+    }
 
     _computeNavLink(query, offset, direction, changesPerPage) {
       // Offset could be a string when passed from the router.
@@ -211,32 +221,32 @@
       const limit = this._limitFor(query, changesPerPage);
       const newOffset = Math.max(0, offset + (limit * direction));
       return Gerrit.Nav.getUrlForSearchQuery(query, newOffset);
-    },
+    }
 
     _computePrevArrowClass(offset) {
       return offset === 0 ? 'hide' : '';
-    },
+    }
 
     _computeNextArrowClass(changes) {
       const more = changes.length && changes[changes.length - 1]._more_changes;
       return more ? '' : 'hide';
-    },
+    }
 
     _computeNavClass(loading) {
       return loading || !this._changes || !this._changes.length ? 'hide' : '';
-    },
+    }
 
     _handleNextPage() {
       if (this.$.nextArrow.hidden) { return; }
       page.show(this._computeNavLink(
           this._query, this._offset, 1, this._changesPerPage));
-    },
+    }
 
     _handlePreviousPage() {
       if (this.$.prevArrow.hidden) { return; }
       page.show(this._computeNavLink(
           this._query, this._offset, -1, this._changesPerPage));
-    },
+    }
 
     _changesChanged(changes) {
       this._userId = null;
@@ -255,28 +265,30 @@
       if (REPO_QUERY_PATTERN.test(this._query)) {
         this._repo = changes[0].project;
       }
-    },
+    }
 
     _computeHeaderClass(id) {
       return id ? '' : 'hide';
-    },
+    }
 
     _computePage(offset, changesPerPage) {
       return offset / changesPerPage + 1;
-    },
+    }
 
     _computeLoggedIn(account) {
       return !!(account && Object.keys(account).length > 0);
-    },
+    }
 
     _handleToggleStar(e) {
       this.$.restAPI.saveChangeStarred(e.detail.change._number,
           e.detail.starred);
-    },
+    }
 
     _handleToggleReviewed(e) {
       this.$.restAPI.saveChangeReviewed(e.detail.change._number,
           e.detail.reviewed);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeListView.is, GrChangeListView);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.html b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.html
index 2367aac..08a83af 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-list-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.html b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.html
index 699f07a..8fdb90c 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.html
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.html
@@ -31,7 +31,9 @@
 
 <dom-module id="gr-change-list">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-change-list-styles">
       #changeList {
         border-collapse: collapse;
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.js b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.js
index e32c773..5ac4fcd 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.js
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list.js
@@ -22,9 +22,25 @@
   const LABEL_PREFIX_INVALID_PROLOG = 'Invalid-Prolog-Rules-Label-Name--';
   const MAX_SHORTCUT_CHARS = 5;
 
-  Polymer({
-    is: 'gr-change-list',
-
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.ChangeTableMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrChangeList extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.ChangeTableBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.RESTClientBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-list'; }
     /**
      * Fired when next page key shortcut was pressed.
      *
@@ -37,28 +53,25 @@
      * @event previous-page
      */
 
-    hostAttributes: {
-      tabindex: 0,
-    },
-
-    properties: {
+    static get properties() {
+      return {
       /**
        * The logged-in user's account, or an empty object if no user is logged
        * in.
        */
-      account: {
-        type: Object,
-        value: null,
-      },
-      /**
+        account: {
+          type: Object,
+          value: null,
+        },
+        /**
        * An array of ChangeInfo objects to render.
        * https://gerrit-review.googlesource.com/Documentation/rest-api-changes.html#change-info
        */
-      changes: {
-        type: Array,
-        observer: '_changesChanged',
-      },
-      /**
+        changes: {
+          type: Array,
+          observer: '_changesChanged',
+        },
+        /**
        * ChangeInfo objects grouped into arrays. The sections and changes
        * properties should not be used together.
        *
@@ -68,56 +81,46 @@
        *   results: !Array<!Object>
        * }>}
        */
-      sections: {
-        type: Array,
-        value() { return []; },
-      },
-      labelNames: {
-        type: Array,
-        computed: '_computeLabelNames(sections)',
-      },
-      _dynamicHeaderEndpoints: {
-        type: Array,
-      },
-      selectedIndex: {
-        type: Number,
-        notify: true,
-      },
-      showNumber: Boolean, // No default value to prevent flickering.
-      showStar: {
-        type: Boolean,
-        value: false,
-      },
-      showReviewedState: {
-        type: Boolean,
-        value: false,
-      },
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      changeTableColumns: Array,
-      visibleChangeTableColumns: Array,
-      preferences: Object,
-    },
+        sections: {
+          type: Array,
+          value() { return []; },
+        },
+        labelNames: {
+          type: Array,
+          computed: '_computeLabelNames(sections)',
+        },
+        _dynamicHeaderEndpoints: {
+          type: Array,
+        },
+        selectedIndex: {
+          type: Number,
+          notify: true,
+        },
+        showNumber: Boolean, // No default value to prevent flickering.
+        showStar: {
+          type: Boolean,
+          value: false,
+        },
+        showReviewedState: {
+          type: Boolean,
+          value: false,
+        },
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
+        changeTableColumns: Array,
+        visibleChangeTableColumns: Array,
+        preferences: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.ChangeTableBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.RESTClientBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
-
-    listeners: {
-      keydown: '_scopedKeydownHandler',
-    },
-
-    observers: [
-      '_sectionsChanged(sections.*)',
-      '_computePreferences(account, preferences)',
-    ],
+    static get observers() {
+      return [
+        '_sectionsChanged(sections.*)',
+        '_computePreferences(account, preferences)',
+      ];
+    }
 
     keyboardShortcuts() {
       return {
@@ -130,14 +133,26 @@
         [this.Shortcut.TOGGLE_CHANGE_STAR]: '_toggleChangeStar',
         [this.Shortcut.REFRESH_CHANGE_LIST]: '_refreshChangeList',
       };
-    },
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('keydown',
+          e => this._scopedKeydownHandler(e));
+    }
+
+    ready() {
+      super.ready();
+      this._ensureAttribute('tabindex', 0);
+    }
 
     attached() {
+      super.attached();
       Gerrit.awaitPluginsLoaded().then(() => {
         this._dynamicHeaderEndpoints = Gerrit._endpoints.getDynamicEndpoints(
             'change-list-header');
       });
-    },
+    }
 
     /**
      * Iron-a11y-keys-behavior catches keyboard events globally. Some keyboard
@@ -151,11 +166,11 @@
         // Enter.
         this._openChange(e);
       }
-    },
+    }
 
     _lowerCase(column) {
       return column.toLowerCase();
-    },
+    }
 
     _computePreferences(account, preferences) {
       // Polymer 2: check for undefined
@@ -169,19 +184,19 @@
         this.showNumber = !!(preferences &&
             preferences.legacycid_in_change_table);
         this.visibleChangeTableColumns = preferences.change_table.length > 0 ?
-            this.getVisibleColumns(preferences.change_table) : this.columnNames;
+          this.getVisibleColumns(preferences.change_table) : this.columnNames;
       } else {
         // Not logged in.
         this.showNumber = false;
         this.visibleChangeTableColumns = this.columnNames;
       }
-    },
+    }
 
     _computeColspan(changeTableColumns, labelNames) {
       if (!changeTableColumns || !labelNames) return;
       return changeTableColumns.length + labelNames.length +
           NUMBER_FIXED_COLUMNS;
-    },
+    }
 
     _computeLabelNames(sections) {
       if (!sections) { return []; }
@@ -198,7 +213,7 @@
         }
       }
       return labels.sort();
-    },
+    }
 
     _computeLabelShortcut(labelName) {
       if (labelName.startsWith(LABEL_PREFIX_INVALID_PROLOG)) {
@@ -210,11 +225,11 @@
             return a + i[0].toUpperCase();
           }, '')
           .slice(0, MAX_SHORTCUT_CHARS);
-    },
+    }
 
     _changesChanged(changes) {
       this.sections = changes ? [{results: changes}] : [];
-    },
+    }
 
     _processQuery(query) {
       let tokens = query.split(' ');
@@ -225,11 +240,11 @@
         });
       });
       return tokens.join(' ');
-    },
+    }
 
     _sectionHref(query) {
       return Gerrit.Nav.getUrlForSearchQuery(this._processQuery(query));
-    },
+    }
 
     /**
      * Maps an index local to a particular section to the absolute index
@@ -245,19 +260,19 @@
         idx += this.sections[i].results.length;
       }
       return idx + localIndex;
-    },
+    }
 
     _computeItemSelected(sectionIndex, index, selectedIndex) {
       const idx = this._computeItemAbsoluteIndex(sectionIndex, index);
       return idx == selectedIndex;
-    },
+    }
 
     _computeItemNeedsReview(account, change, showReviewedState) {
       return showReviewedState && !change.reviewed &&
           !change.work_in_progress &&
           this.changeIsOpen(change) &&
           (!account || account._account_id != change.owner._account_id);
-    },
+    }
 
     _computeItemHighlight(account, change) {
       // Do not show the assignee highlight if the change is not open.
@@ -267,7 +282,7 @@
         return false;
       }
       return account._account_id === change.assignee._account_id;
-    },
+    }
 
     _nextChange(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -275,7 +290,7 @@
 
       e.preventDefault();
       this.$.cursor.next();
-    },
+    }
 
     _prevChange(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -283,7 +298,7 @@
 
       e.preventDefault();
       this.$.cursor.previous();
-    },
+    }
 
     _openChange(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -291,7 +306,7 @@
 
       e.preventDefault();
       Gerrit.Nav.navigateToChange(this._changeForIndex(this.selectedIndex));
-    },
+    }
 
     _nextPage(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -301,7 +316,7 @@
 
       e.preventDefault();
       this.fire('next-page');
-    },
+    }
 
     _prevPage(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -311,7 +326,7 @@
 
       e.preventDefault();
       this.fire('previous-page');
-    },
+    }
 
     _toggleChangeReviewed(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -319,7 +334,7 @@
 
       e.preventDefault();
       this._toggleReviewedForIndex(this.selectedIndex);
-    },
+    }
 
     _toggleReviewedForIndex(index) {
       const changeEls = this._getListItems();
@@ -329,18 +344,18 @@
 
       const changeEl = changeEls[index];
       changeEl.toggleReviewed();
-    },
+    }
 
     _refreshChangeList(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
 
       e.preventDefault();
       this._reloadWindow();
-    },
+    }
 
     _reloadWindow() {
       window.location.reload();
-    },
+    }
 
     _toggleChangeStar(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -348,7 +363,7 @@
 
       e.preventDefault();
       this._toggleStarForIndex(this.selectedIndex);
-    },
+    }
 
     _toggleStarForIndex(index) {
       const changeEls = this._getListItems();
@@ -358,7 +373,7 @@
 
       const changeEl = changeEls[index];
       changeEl.$$('gr-change-star').toggleStar();
-    },
+    }
 
     _changeForIndex(index) {
       const changeEls = this._getListItems();
@@ -366,12 +381,12 @@
         return changeEls[index].change;
       }
       return null;
-    },
+    }
 
     _getListItems() {
       return Array.from(
           Polymer.dom(this.root).querySelectorAll('gr-change-list-item'));
-    },
+    }
 
     _sectionsChanged() {
       // Flush DOM operations so that the list item elements will be loaded.
@@ -379,14 +394,16 @@
         this.$.cursor.stops = this._getListItems();
         this.$.cursor.moveToStart();
       });
-    },
+    }
 
     _isOutgoing(section) {
       return !!section.isOutgoing;
-    },
+    }
 
     _isEmpty(section) {
       return !section.results.length;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeList.is, GrChangeList);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list_test.html b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list_test.html
index 87b1665..75fd167 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list/gr-change-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -113,7 +113,7 @@
 
     test('computed fields', () => {
       assert.equal(element._computeLabelNames(
-            [{results: [{_number: 0, labels: {}}]}]).length, 0);
+          [{results: [{_number: 0, labels: {}}]}]).length, 0);
       assert.equal(element._computeLabelNames([
         {results: [
           {_number: 0, labels: {Verified: {approved: {}}}},
diff --git a/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help.js b/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help.js
index 19e7a25..e6caacb 100644
--- a/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help.js
+++ b/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help.js
@@ -17,8 +17,10 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-create-change-help',
+  class GrCreateChangeHelp extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-create-change-help'; }
 
     /**
      * Fired when the "Create change" button is tapped.
@@ -30,6 +32,8 @@
       e.preventDefault();
       this.dispatchEvent(
           new CustomEvent('create-tap', {bubbles: true, composed: true}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateChangeHelp.is, GrCreateChangeHelp);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help_test.html b/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help_test.html
index c43d62a..f10fbf2 100644
--- a/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-create-change-help/gr-create-change-help_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-change-help</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog.js b/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog.js
index 5abb257..303128b 100644
--- a/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog.js
+++ b/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog.js
@@ -23,37 +23,43 @@
     PUSH_PREFIX: 'git push origin HEAD:refs/for/',
   };
 
-  Polymer({
-    is: 'gr-create-commands-dialog',
+  class GrCreateCommandsDialog extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-create-commands-dialog'; }
 
-    properties: {
-      branch: String,
-      _createNewCommitCommand: {
-        type: String,
-        readonly: true,
-        value: Commands.CREATE,
-      },
-      _amendExistingCommitCommand: {
-        type: String,
-        readonly: true,
-        value: Commands.AMEND,
-      },
-      _pushCommand: {
-        type: String,
-        computed: '_computePushCommand(branch)',
-      },
-    },
+    static get properties() {
+      return {
+        branch: String,
+        _createNewCommitCommand: {
+          type: String,
+          readonly: true,
+          value: Commands.CREATE,
+        },
+        _amendExistingCommitCommand: {
+          type: String,
+          readonly: true,
+          value: Commands.AMEND,
+        },
+        _pushCommand: {
+          type: String,
+          computed: '_computePushCommand(branch)',
+        },
+      };
+    }
 
     open() {
       this.$.commandsOverlay.open();
-    },
+    }
 
     _handleClose() {
       this.$.commandsOverlay.close();
-    },
+    }
 
     _computePushCommand(branch) {
       return Commands.PUSH_PREFIX + branch;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateCommandsDialog.is, GrCreateCommandsDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog_test.html b/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog_test.html
index 89ad573..2228b50 100644
--- a/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-create-commands-dialog/gr-create-commands-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-create-commands-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change-list/gr-create-destination-dialog/gr-create-destination-dialog.js b/polygerrit-ui/app/elements/change-list/gr-create-destination-dialog/gr-create-destination-dialog.js
index d601cad..3652e70 100644
--- a/polygerrit-ui/app/elements/change-list/gr-create-destination-dialog/gr-create-destination-dialog.js
+++ b/polygerrit-ui/app/elements/change-list/gr-create-destination-dialog/gr-create-destination-dialog.js
@@ -23,37 +23,44 @@
    *
    * @event confirm
    */
+  class GrCreateDestinationDialog extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-create-destination-dialog'; }
 
-  Polymer({
-    is: 'gr-create-destination-dialog',
+    static get properties() {
+      return {
+        _repo: String,
+        _branch: String,
+        _repoAndBranchSelected: {
+          type: Boolean,
+          value: false,
+          computed: '_computeRepoAndBranchSelected(_repo, _branch)',
+        },
+      };
+    }
 
-    properties: {
-      _repo: String,
-      _branch: String,
-      _repoAndBranchSelected: {
-        type: Boolean,
-        value: false,
-        computed: '_computeRepoAndBranchSelected(_repo, _branch)',
-      },
-    },
     open() {
       this._repo = '';
       this._branch = '';
       this.$.createOverlay.open();
-    },
+    }
 
     _handleClose() {
       this.$.createOverlay.close();
-    },
+    }
 
     _pickerConfirm() {
       this.$.createOverlay.close();
       const detail = {repo: this._repo, branch: this._branch};
       this.dispatchEvent(new CustomEvent('confirm', {detail, bubbles: false}));
-    },
+    }
 
     _computeRepoAndBranchSelected(repo, branch) {
       return !!(repo && branch);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCreateDestinationDialog.is,
+      GrCreateDestinationDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
index aab0cba..69cc070 100644
--- a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
+++ b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view.js
@@ -19,65 +19,72 @@
 
   const PROJECT_PLACEHOLDER_PATTERN = /\$\{project\}/g;
 
-  Polymer({
-    is: 'gr-dashboard-view',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrDashboardView extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-dashboard-view'; }
     /**
      * Fired when the title of the page should change.
      *
      * @event title-change
      */
 
-    properties: {
-      account: {
-        type: Object,
-        value: null,
-      },
-      preferences: Object,
-      /** @type {{ selectedChangeIndex: number }} */
-      viewState: Object,
-
-      /** @type {{ project: string, user: string }} */
-      params: {
-        type: Object,
-      },
-
-      createChangeTap: {
-        type: Function,
-        value() {
-          return this._createChangeTap.bind(this);
+    static get properties() {
+      return {
+        account: {
+          type: Object,
+          value: null,
         },
-      },
+        preferences: Object,
+        /** @type {{ selectedChangeIndex: number }} */
+        viewState: Object,
 
-      _results: Array,
+        /** @type {{ project: string, user: string }} */
+        params: {
+          type: Object,
+        },
 
-      /**
+        createChangeTap: {
+          type: Function,
+          value() {
+            return this._createChangeTap.bind(this);
+          },
+        },
+
+        _results: Array,
+
+        /**
        * For showing a "loading..." string during ajax requests.
        */
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
 
-      _showDraftsBanner: {
-        type: Boolean,
-        value: false,
-      },
+        _showDraftsBanner: {
+          type: Boolean,
+          value: false,
+        },
 
-      _showNewUserHelp: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _showNewUserHelp: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    observers: [
-      '_paramsChanged(params.*)',
-    ],
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
+    static get observers() {
+      return [
+        '_paramsChanged(params.*)',
+      ];
+    }
 
     get options() {
       return this.listChangesOptionsToHex(
@@ -85,11 +92,12 @@
           this.ListChangesOption.DETAILED_ACCOUNTS,
           this.ListChangesOption.REVIEWED
       );
-    },
+    }
 
     attached() {
+      super.attached();
       this._loadPreferences();
-    },
+    }
 
     _loadPreferences() {
       return this.$.restAPI.getLoggedIn().then(loggedIn => {
@@ -101,7 +109,7 @@
           this.preferences = {};
         }
       });
-    },
+    }
 
     _getProjectDashboard(project, dashboard) {
       const errFn = response => {
@@ -109,33 +117,33 @@
       };
       return this.$.restAPI.getDashboard(
           project, dashboard, errFn).then(response => {
-            if (!response) {
-              return;
-            }
+        if (!response) {
+          return;
+        }
+        return {
+          title: response.title,
+          sections: response.sections.map(section => {
+            const suffix = response.foreach ? ' ' + response.foreach : '';
             return {
-              title: response.title,
-              sections: response.sections.map(section => {
-                const suffix = response.foreach ? ' ' + response.foreach : '';
-                return {
-                  name: section.name,
-                  query: (section.query + suffix).replace(
-                      PROJECT_PLACEHOLDER_PATTERN, project),
-                };
-              }),
+              name: section.name,
+              query: (section.query + suffix).replace(
+                  PROJECT_PLACEHOLDER_PATTERN, project),
             };
-          });
-    },
+          }),
+        };
+      });
+    }
 
     _computeTitle(user) {
       if (!user || user === 'self') {
         return 'My Reviews';
       }
       return 'Dashboard for ' + user;
-    },
+    }
 
     _isViewActive(params) {
       return params.view === Gerrit.Nav.View.DASHBOARD;
-    },
+    }
 
     _paramsChanged(paramsChangeRecord) {
       const params = paramsChangeRecord.base;
@@ -145,7 +153,7 @@
       }
 
       return this._reload();
-    },
+    }
 
     /**
      * Reloads the element.
@@ -156,11 +164,11 @@
       this._loading = true;
       const {project, dashboard, title, user, sections} = this.params;
       const dashboardPromise = project ?
-          this._getProjectDashboard(project, dashboard) :
-          Promise.resolve(Gerrit.Nav.getUserDashboard(
-              user,
-              sections,
-              title || this._computeTitle(user)));
+        this._getProjectDashboard(project, dashboard) :
+        Promise.resolve(Gerrit.Nav.getUserDashboard(
+            user,
+            sections,
+            title || this._computeTitle(user)));
 
       const checkForNewUser = !project && user === 'self';
       return dashboardPromise
@@ -179,7 +187,7 @@
             });
             console.warn(err);
           }).then(() => { this._loading = false; });
-    },
+    }
 
     /**
      * Fetches the changes for each dashboard section and sets this._results
@@ -194,8 +202,8 @@
 
       const queries = res.sections
           .map(section => section.suffixForDashboard ?
-              section.query + ' ' + section.suffixForDashboard :
-              section.query);
+            section.query + ' ' + section.suffixForDashboard :
+            section.query);
 
       if (checkForNewUser) {
         queries.push('owner:self limit:1');
@@ -215,10 +223,10 @@
               results,
               isOutgoing: res.sections[i].isOutgoing,
             })).filter((section, i) => i < res.sections.length && (
-                !res.sections[i].hideIfEmpty ||
+              !res.sections[i].hideIfEmpty ||
                 section.results.length));
           });
-    },
+    }
 
     _computeSectionCountLabel(changes) {
       if (!changes || !changes.length || changes.length == 0) {
@@ -228,7 +236,7 @@
       const numChanges = changes.length;
       const andMore = more ? ' and more' : '';
       return `(${numChanges}${andMore})`;
-    },
+    }
 
     _computeUserHeaderClass(params) {
       if (!params || !!params.project || !params.user
@@ -236,17 +244,17 @@
         return 'hide';
       }
       return '';
-    },
+    }
 
     _handleToggleStar(e) {
       this.$.restAPI.saveChangeStarred(e.detail.change._number,
           e.detail.starred);
-    },
+    }
 
     _handleToggleReviewed(e) {
       this.$.restAPI.saveChangeReviewed(e.detail.change._number,
           e.detail.reviewed);
-    },
+    }
 
     /**
      * Banner is shown if a user is on their own dashboard and they have draft
@@ -265,15 +273,15 @@
       if (!closedChanges.length) { return; }
 
       this._showDraftsBanner = true;
-    },
+    }
 
     _computeBannerClass(show) {
       return show ? '' : 'hide';
-    },
+    }
 
     _handleOpenDeleteDialog() {
       this.$.confirmDeleteOverlay.open();
-    },
+    }
 
     _handleConfirmDelete() {
       this.$.confirmDeleteDialog.disabled = true;
@@ -281,23 +289,25 @@
         this._closeConfirmDeleteOverlay();
         this._reload();
       });
-    },
+    }
 
     _closeConfirmDeleteOverlay() {
       this.$.confirmDeleteOverlay.close();
-    },
+    }
 
     _computeDraftsLink() {
       return Gerrit.Nav.getUrlForSearchQuery('has:draft -is:open');
-    },
+    }
 
     _createChangeTap(e) {
       this.$.destinationDialog.open();
-    },
+    }
 
     _handleDestinationConfirm(e) {
       this.$.commandsDialog.branch = e.detail.branch;
       this.$.commandsDialog.open();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDashboardView.is, GrDashboardView);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view_test.html b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view_test.html
index 41d4192..0d15d13 100644
--- a/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-dashboard-view/gr-dashboard-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-dashboard-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change-list/gr-embed-dashboard/gr-embed-dashboard.js b/polygerrit-ui/app/elements/change-list/gr-embed-dashboard/gr-embed-dashboard.js
index acc4295..96dcb98 100644
--- a/polygerrit-ui/app/elements/change-list/gr-embed-dashboard/gr-embed-dashboard.js
+++ b/polygerrit-ui/app/elements/change-list/gr-embed-dashboard/gr-embed-dashboard.js
@@ -17,14 +17,20 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-embed-dashboard',
+  class GrEmbedDashboard extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-embed-dashboard'; }
 
-    properties: {
-      account: Object,
-      sections: Array,
-      preferences: Object,
-      showNewUserHelp: Boolean,
-    },
-  });
+    static get properties() {
+      return {
+        account: Object,
+        sections: Array,
+        preferences: Object,
+        showNewUserHelp: Boolean,
+      };
+    }
+  }
+
+  customElements.define(GrEmbedDashboard.is, GrEmbedDashboard);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.html b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.html
index 0b4459c..5d4b8a3 100644
--- a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.html
+++ b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.html
@@ -24,8 +24,12 @@
 
 <dom-module id="gr-repo-header">
   <template>
-    <style include="shared-styles"></style>
-    <style include="dashboard-header-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="dashboard-header-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="info">
       <h1 class$="name">
         [[repo]]
diff --git a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.js b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.js
index 7ae4dab..c603c45 100644
--- a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.js
+++ b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header.js
@@ -17,18 +17,22 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-repo-header',
+  class GrRepoHeader extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-repo-header'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?String} */
-      repo: {
-        type: String,
-        observer: '_repoChanged',
-      },
-      /** @type {String|null} */
-      _repoUrl: String,
-    },
+        repo: {
+          type: String,
+          observer: '_repoChanged',
+        },
+        /** @type {String|null} */
+        _repoUrl: String,
+      };
+    }
 
     _repoChanged(repoName) {
       if (!repoName) {
@@ -36,6 +40,8 @@
         return;
       }
       this._repoUrl = Gerrit.Nav.getUrlForRepo(repoName);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoHeader.is, GrRepoHeader);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header_test.html b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header_test.html
index 266818e..85eb509 100644
--- a/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-repo-header/gr-repo-header_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-header</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.html b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.html
index fed1c12..8175849 100644
--- a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.html
+++ b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.html
@@ -27,7 +27,9 @@
 
 <dom-module id="gr-user-header">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="dashboard-header-styles">
       .name {
         display: inline-block;
diff --git a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.js b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.js
index 6942705..af8af3f 100644
--- a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.js
+++ b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header.js
@@ -17,40 +17,44 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-user-header',
+  class GrUserHeader extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-user-header'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?String} */
-      userId: {
-        type: String,
-        observer: '_accountChanged',
-      },
+        userId: {
+          type: String,
+          observer: '_accountChanged',
+        },
 
-      showDashboardLink: {
-        type: Boolean,
-        value: false,
-      },
+        showDashboardLink: {
+          type: Boolean,
+          value: false,
+        },
 
-      loggedIn: {
-        type: Boolean,
-        value: false,
-      },
+        loggedIn: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * @type {?{name: ?, email: ?, registered_on: ?}}
        */
-      _accountDetails: {
-        type: Object,
-        value: null,
-      },
+        _accountDetails: {
+          type: Object,
+          value: null,
+        },
 
-      /** @type {?String} */
-      _status: {
-        type: String,
-        value: null,
-      },
-    },
+        /** @type {?String} */
+        _status: {
+          type: String,
+          value: null,
+        },
+      };
+    }
 
     _accountChanged(userId) {
       if (!userId) {
@@ -65,19 +69,19 @@
       this.$.restAPI.getAccountStatus(userId).then(status => {
         this._status = status;
       });
-    },
+    }
 
     _computeDisplayClass(status) {
       return status ? ' ' : 'hide';
-    },
+    }
 
     _computeDetail(accountDetails, name) {
       return accountDetails ? accountDetails[name] : '';
-    },
+    }
 
     _computeStatusClass(accountDetails) {
       return this._computeDetail(accountDetails, 'status') ? '' : 'hide';
-    },
+    }
 
     _computeDashboardUrl(accountDetails) {
       if (!accountDetails) { return null; }
@@ -85,11 +89,13 @@
       const email = accountDetails.email;
       if (!id && !email ) { return null; }
       return Gerrit.Nav.getUrlForUserDashboard(id ? id : email);
-    },
+    }
 
     _computeDashboardLinkClass(showDashboardLink, loggedIn) {
       return showDashboardLink && loggedIn ?
-          'dashboardLink' : 'dashboardLink hide';
-    },
-  });
+        'dashboardLink' : 'dashboardLink hide';
+    }
+  }
+
+  customElements.define(GrUserHeader.is, GrUserHeader);
 })();
diff --git a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header_test.html b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header_test.html
index e837a5b..9e04ecd 100644
--- a/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header_test.html
+++ b/polygerrit-ui/app/elements/change-list/gr-user-header/gr-user-header_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-user-header</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.html b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.html
index 000756f..6703651 100644
--- a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.html
+++ b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.html
@@ -36,6 +36,7 @@
 <link rel="import" href="../gr-confirm-move-dialog/gr-confirm-move-dialog.html">
 <link rel="import" href="../gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.html">
 <link rel="import" href="../gr-confirm-revert-dialog/gr-confirm-revert-dialog.html">
+<link rel="import" href="../gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.html">
 <link rel="import" href="../gr-confirm-submit-dialog/gr-confirm-submit-dialog.html">
 <link rel="import" href="../../../styles/shared-styles.html">
 
@@ -192,12 +193,8 @@
           hidden></gr-confirm-cherrypick-dialog>
       <gr-confirm-cherrypick-conflict-dialog id="confirmCherrypickConflict"
           class="confirmDialog"
-          change-status="[[changeStatus]]"
-          commit-message="[[commitMessage]]"
-          commit-num="[[commitNum]]"
           on-confirm="_handleCherrypickConflictConfirm"
           on-cancel="_handleConfirmDialogCancel"
-          project="[[change.project]]"
           hidden></gr-confirm-cherrypick-conflict-dialog>
       <gr-confirm-move-dialog id="confirmMove"
           class="confirmDialog"
@@ -210,6 +207,11 @@
           on-confirm="_handleRevertDialogConfirm"
           on-cancel="_handleConfirmDialogCancel"
           hidden></gr-confirm-revert-dialog>
+      <gr-confirm-revert-submission-dialog id="confirmRevertSubmissionDialog"
+          class="confirmDialog"
+          on-confirm="_handleRevertSubmissionDialogConfirm"
+          on-cancel="_handleConfirmDialogCancel"
+          hidden></gr-confirm-revert-submission-dialog>
       <gr-confirm-abandon-dialog id="confirmAbandonDialog"
           class="confirmDialog"
           on-confirm="_handleAbandonDialogConfirm"
@@ -267,6 +269,25 @@
           Do you really want to delete the edit?
         </div>
       </gr-dialog>
+      <gr-dialog
+        id="showRevertSubmissionChangesDialog"
+        class="confirmDialog"
+        confirm-label="Close"
+        cancel-label=''
+        on-confirm="_handleShowRevertSubmissionChangesConfirm">
+        <div class="header" slot="header">
+          Reverted Changes
+        </div>
+        <div class="main" slot="main">
+          <template is="dom-repeat" items="[[_revertChanges]]">
+            <div>
+              <a href$="[[item.link]]" target="_blank">
+                Change [[item._number]]
+              </a>
+            </div>
+          </template>
+        </div>
+      </gr-dialog>
     </gr-overlay>
     <gr-js-api-interface id="jsAPI"></gr-js-api-interface>
     <gr-rest-api-interface id="restAPI"></gr-rest-api-interface>
diff --git a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.js b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.js
index fe70239..8ad2a06 100644
--- a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.js
+++ b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions.js
@@ -64,6 +64,7 @@
     REBASE_EDIT: 'rebaseEdit',
     RESTORE: 'restore',
     REVERT: 'revert',
+    REVERT_SUBMISSION: 'revert_submission',
     REVIEWED: 'reviewed',
     STOP_EDIT: 'stopEdit',
     UNIGNORE: 'unignore',
@@ -86,6 +87,7 @@
     rebase: 'Rebasing...',
     restore: 'Restoring...',
     revert: 'Reverting...',
+    revert_submission: 'Reverting Submission...',
     submit: 'Submitting...',
   };
 
@@ -180,6 +182,7 @@
     ChangeActions.REBASE_EDIT,
     ChangeActions.RESTORE,
     ChangeActions.REVERT,
+    ChangeActions.REVERT_SUBMISSION,
     ChangeActions.STOP_EDIT,
     QUICK_APPROVE_ACTION.key,
     RevisionActions.REBASE,
@@ -189,9 +192,19 @@
   const AWAIT_CHANGE_ATTEMPTS = 5;
   const AWAIT_CHANGE_TIMEOUT_MS = 1000;
 
-  Polymer({
-    is: 'gr-change-actions',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrChangeActions extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-actions'; }
     /**
      * Fired when the change should be reloaded.
      *
@@ -216,7 +229,15 @@
      * @event show-error
      */
 
-    properties: {
+    constructor() {
+      super();
+      this.ActionType = ActionType;
+      this.ChangeActions = ChangeActions;
+      this.RevisionActions = RevisionActions;
+    }
+
+    static get properties() {
+      return {
       /**
        * @type {{
        *    _number: number,
@@ -226,217 +247,218 @@
        *    subject: string,
        *  }}
        */
-      change: Object,
-      actions: {
-        type: Object,
-        value() { return {}; },
-      },
-      primaryActionKeys: {
-        type: Array,
-        value() {
-          return [
-            RevisionActions.SUBMIT,
-          ];
+        change: Object,
+        actions: {
+          type: Object,
+          value() { return {}; },
         },
-      },
-      disableEdit: {
-        type: Boolean,
-        value: false,
-      },
-      _hasKnownChainState: {
-        type: Boolean,
-        value: false,
-      },
-      _hideQuickApproveAction: {
-        type: Boolean,
-        value: false,
-      },
-      changeNum: String,
-      changeStatus: String,
-      commitNum: String,
-      hasParent: {
-        type: Boolean,
-        observer: '_computeChainState',
-      },
-      latestPatchNum: String,
-      commitMessage: {
-        type: String,
-        value: '',
-      },
-      /** @type {?} */
-      revisionActions: {
-        type: Object,
-        notify: true,
-        value() { return {}; },
-      },
-      // If property binds directly to [[revisionActions.submit]] it is not
-      // updated when revisionActions doesn't contain submit action.
-      /** @type {?} */
-      _revisionSubmitAction: {
-        type: Object,
-        computed: '_getSubmitAction(revisionActions)',
-      },
-      // If property binds directly to [[revisionActions.rebase]] it is not
-      // updated when revisionActions doesn't contain rebase action.
-      /** @type {?} */
-      _revisionRebaseAction: {
-        type: Object,
-        computed: '_getRebaseAction(revisionActions)',
-      },
-      privateByDefault: String,
+        primaryActionKeys: {
+          type: Array,
+          value() {
+            return [
+              RevisionActions.SUBMIT,
+            ];
+          },
+        },
+        disableEdit: {
+          type: Boolean,
+          value: false,
+        },
+        _hasKnownChainState: {
+          type: Boolean,
+          value: false,
+        },
+        _hideQuickApproveAction: {
+          type: Boolean,
+          value: false,
+        },
+        changeNum: String,
+        changeStatus: String,
+        commitNum: String,
+        hasParent: {
+          type: Boolean,
+          observer: '_computeChainState',
+        },
+        latestPatchNum: String,
+        commitMessage: {
+          type: String,
+          value: '',
+        },
+        /** @type {?} */
+        revisionActions: {
+          type: Object,
+          notify: true,
+          value() { return {}; },
+        },
+        // If property binds directly to [[revisionActions.submit]] it is not
+        // updated when revisionActions doesn't contain submit action.
+        /** @type {?} */
+        _revisionSubmitAction: {
+          type: Object,
+          computed: '_getSubmitAction(revisionActions)',
+        },
+        // If property binds directly to [[revisionActions.rebase]] it is not
+        // updated when revisionActions doesn't contain rebase action.
+        /** @type {?} */
+        _revisionRebaseAction: {
+          type: Object,
+          computed: '_getRebaseAction(revisionActions)',
+        },
+        privateByDefault: String,
 
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _actionLoadingMessage: {
-        type: String,
-        value: '',
-      },
-      _allActionValues: {
-        type: Array,
-        computed: '_computeAllActions(actions.*, revisionActions.*,' +
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _actionLoadingMessage: {
+          type: String,
+          value: '',
+        },
+        _allActionValues: {
+          type: Array,
+          computed: '_computeAllActions(actions.*, revisionActions.*,' +
             'primaryActionKeys.*, _additionalActions.*, change, ' +
             '_actionPriorityOverrides.*)',
-      },
-      _topLevelActions: {
-        type: Array,
-        computed: '_computeTopLevelActions(_allActionValues.*, ' +
-            '_hiddenActions.*, _overflowActions.*)',
-        observer: '_filterPrimaryActions',
-      },
-      _topLevelPrimaryActions: Array,
-      _topLevelSecondaryActions: Array,
-      _menuActions: {
-        type: Array,
-        computed: '_computeMenuActions(_allActionValues.*, _hiddenActions.*, ' +
-            '_overflowActions.*)',
-      },
-      _overflowActions: {
-        type: Array,
-        value() {
-          const value = [
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.WIP,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.DELETE,
-            },
-            {
-              type: ActionType.REVISION,
-              key: RevisionActions.CHERRYPICK,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.MOVE,
-            },
-            {
-              type: ActionType.REVISION,
-              key: RevisionActions.DOWNLOAD,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.IGNORE,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.UNIGNORE,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.REVIEWED,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.UNREVIEWED,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.PRIVATE,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.PRIVATE_DELETE,
-            },
-            {
-              type: ActionType.CHANGE,
-              key: ChangeActions.FOLLOW_UP,
-            },
-          ];
-          return value;
         },
-      },
-      _actionPriorityOverrides: {
-        type: Array,
-        value() { return []; },
-      },
-      _additionalActions: {
-        type: Array,
-        value() { return []; },
-      },
-      _hiddenActions: {
-        type: Array,
-        value() { return []; },
-      },
-      _disabledMenuActions: {
-        type: Array,
-        value() { return []; },
-      },
-      // editPatchsetLoaded == "does the current selected patch range have
-      // 'edit' as one of either basePatchNum or patchNum".
-      editPatchsetLoaded: {
-        type: Boolean,
-        value: false,
-      },
-      // editMode == "is edit mode enabled in the file list".
-      editMode: {
-        type: Boolean,
-        value: false,
-      },
-      editBasedOnCurrentPatchSet: {
-        type: Boolean,
-        value: true,
-      },
-    },
+        _topLevelActions: {
+          type: Array,
+          computed: '_computeTopLevelActions(_allActionValues.*, ' +
+            '_hiddenActions.*, _overflowActions.*)',
+          observer: '_filterPrimaryActions',
+        },
+        _topLevelPrimaryActions: Array,
+        _topLevelSecondaryActions: Array,
+        _menuActions: {
+          type: Array,
+          computed: '_computeMenuActions(_allActionValues.*, ' +
+            '_hiddenActions.*, _overflowActions.*)',
+        },
+        _overflowActions: {
+          type: Array,
+          value() {
+            const value = [
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.WIP,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.DELETE,
+              },
+              {
+                type: ActionType.REVISION,
+                key: RevisionActions.CHERRYPICK,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.MOVE,
+              },
+              {
+                type: ActionType.REVISION,
+                key: RevisionActions.DOWNLOAD,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.IGNORE,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.UNIGNORE,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.REVIEWED,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.UNREVIEWED,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.PRIVATE,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.PRIVATE_DELETE,
+              },
+              {
+                type: ActionType.CHANGE,
+                key: ChangeActions.FOLLOW_UP,
+              },
+            ];
+            return value;
+          },
+        },
+        _actionPriorityOverrides: {
+          type: Array,
+          value() { return []; },
+        },
+        _additionalActions: {
+          type: Array,
+          value() { return []; },
+        },
+        _hiddenActions: {
+          type: Array,
+          value() { return []; },
+        },
+        _disabledMenuActions: {
+          type: Array,
+          value() { return []; },
+        },
+        // editPatchsetLoaded == "does the current selected patch range have
+        // 'edit' as one of either basePatchNum or patchNum".
+        editPatchsetLoaded: {
+          type: Boolean,
+          value: false,
+        },
+        // editMode == "is edit mode enabled in the file list".
+        editMode: {
+          type: Boolean,
+          value: false,
+        },
+        editBasedOnCurrentPatchSet: {
+          type: Boolean,
+          value: true,
+        },
+        _revertChanges: {
+          type: Array,
+          value: [],
+        },
+      };
+    }
 
-    ActionType,
-    ChangeActions,
-    RevisionActions,
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
-
-    observers: [
-      '_actionsChanged(actions.*, revisionActions.*, _additionalActions.*)',
-      '_changeChanged(change)',
-      '_editStatusChanged(editMode, editPatchsetLoaded, ' +
+    static get observers() {
+      return [
+        '_actionsChanged(actions.*, revisionActions.*, _additionalActions.*)',
+        '_changeChanged(change)',
+        '_editStatusChanged(editMode, editPatchsetLoaded, ' +
           'editBasedOnCurrentPatchSet, disableEdit, actions.*, change.*)',
-    ],
+      ];
+    }
 
-    listeners: {
-      'fullscreen-overlay-opened': '_handleHideBackgroundContent',
-      'fullscreen-overlay-closed': '_handleShowBackgroundContent',
-    },
+    created() {
+      super.created();
+      this.addEventListener('fullscreen-overlay-opened',
+          () => this._handleHideBackgroundContent());
+      this.addEventListener('fullscreen-overlay-closed',
+          () => this._handleShowBackgroundContent());
+    }
 
     ready() {
+      super.ready();
       this.$.jsAPI.addElement(this.$.jsAPI.Element.CHANGE_ACTIONS, this);
       this._handleLoadingComplete();
-    },
+    }
 
     _getSubmitAction(revisionActions) {
       return this._getRevisionAction(revisionActions, 'submit', null);
-    },
+    }
 
     _getRebaseAction(revisionActions) {
       return this._getRevisionAction(revisionActions, 'rebase',
-        {rebaseOnCurrent: null}
+          {rebaseOnCurrent: null}
       );
-    },
+    }
 
     _getRevisionAction(revisionActions, actionName, emptyActionValue) {
       if (!revisionActions) {
@@ -448,7 +470,7 @@
         return emptyActionValue;
       }
       return revisionActions[actionName];
-    },
+    }
 
     reload() {
       if (!this.changeNum || !this.latestPatchNum) {
@@ -466,11 +488,11 @@
         this._loading = false;
         throw err;
       });
-    },
+    }
 
     _handleLoadingComplete() {
       Gerrit.awaitPluginsLoaded().then(() => this._loading = false);
-    },
+    }
 
     _updateRebaseAction(revisionActions) {
       if (revisionActions && revisionActions.rebase) {
@@ -482,11 +504,11 @@
         this._parentIsCurrent = true;
       }
       return revisionActions;
-    },
+    }
 
     _changeChanged() {
       this.reload();
-    },
+    }
 
     addActionButton(type, label) {
       if (type !== ActionType.CHANGE && type !== ActionType.REVISION) {
@@ -501,7 +523,7 @@
       };
       this.push('_additionalActions', action);
       return action.__key;
-    },
+    }
 
     removeActionButton(key) {
       const idx = this._indexOfActionButtonWithKey(key);
@@ -509,7 +531,7 @@
         return;
       }
       this.splice('_additionalActions', idx, 1);
-    },
+    }
 
     setActionButtonProp(key, prop, value) {
       this.set([
@@ -517,7 +539,7 @@
         this._indexOfActionButtonWithKey(key),
         prop,
       ], value);
-    },
+    }
 
     setActionOverflow(type, key, overflow) {
       if (type !== ActionType.CHANGE && type !== ActionType.REVISION) {
@@ -534,7 +556,7 @@
       } else if (overflow) {
         this.push('_overflowActions', action);
       }
-    },
+    }
 
     setActionPriority(type, key, priority) {
       if (type !== ActionType.CHANGE && type !== ActionType.REVISION) {
@@ -553,7 +575,7 @@
       } else {
         this.push('_actionPriorityOverrides', action);
       }
-    },
+    }
 
     setActionHidden(type, key, hidden) {
       if (type !== ActionType.CHANGE && type !== ActionType.REVISION) {
@@ -566,7 +588,7 @@
       } else if (!hidden && idx !== -1) {
         this.splice('_hiddenActions', idx, 1);
       }
-    },
+    }
 
     getActionDetails(action) {
       if (this.revisionActions[action]) {
@@ -574,7 +596,7 @@
       } else if (this.actions[action]) {
         return this.actions[action];
       }
-    },
+    }
 
     _indexOfActionButtonWithKey(key) {
       for (let i = 0; i < this._additionalActions.length; i++) {
@@ -583,20 +605,20 @@
         }
       }
       return -1;
-    },
+    }
 
     _getRevisionActions() {
       return this.$.restAPI.getChangeRevisionActions(this.changeNum,
           this.latestPatchNum);
-    },
+    }
 
     _shouldHideActions(actions, loading) {
       return loading || !actions || !actions.base || !actions.base.length;
-    },
+    }
 
     _keyCount(changeRecord) {
       return Object.keys((changeRecord && changeRecord.base) || {}).length;
-    },
+    }
 
     _actionsChanged(actionsChangeRecord, revisionActionsChangeRecord,
         additionalActionsChangeRecord) {
@@ -623,9 +645,9 @@
           this.set('revisionActions.download', DOWNLOAD_ACTION);
         }
       }
-    },
+    }
 
-      /**
+    /**
        * @param {string=} actionName
        */
     _deleteAndNotify(actionName) {
@@ -635,7 +657,7 @@
         // see https://github.com/Polymer/polymer/issues/2631
         this.notifyPath('actions.' + actionName, false);
       }
-    },
+    }
 
     _editStatusChanged(editMode, editPatchsetLoaded,
         editBasedOnCurrentPatchSet, disableEdit) {
@@ -702,13 +724,13 @@
         // Remove edit button.
         this._deleteAndNotify('edit');
       }
-    },
+    }
 
     _getValuesFor(obj) {
       return Object.keys(obj).map(key => {
         return obj[key];
       });
-    },
+    }
 
     _getLabelStatus(label) {
       if (label.approved) {
@@ -720,7 +742,7 @@
       } else {
         return LabelStatus.NEED;
       }
-    },
+    }
 
     /**
      * Get highest score for last missing permitted label for current change.
@@ -768,7 +790,7 @@
         }
       }
       return null;
-    },
+    }
 
     hideQuickApproveAction() {
       this._topLevelSecondaryActions =
@@ -776,7 +798,7 @@
           return sa.key !== QUICK_APPROVE_ACTION.key;
         });
       this._hideQuickApproveAction = true;
-    },
+    }
 
     _getQuickApproveAction() {
       if (this._hideQuickApproveAction) {
@@ -795,7 +817,7 @@
       review.labels[approval.label] = approval.score;
       action.payload = review;
       return action;
-    },
+    }
 
     _getActionValues(actionsChangeRecord, primariesChangeRecord,
         additionalActionsChangeRecord, type) {
@@ -840,7 +862,7 @@
         return Object.assign({}, a);
       });
       return result.concat(additionalActions).concat(pluginActions);
-    },
+    }
 
     _populateActionUrl(action) {
       const patchNum =
@@ -848,7 +870,7 @@
       this.$.restAPI.getChangeActionURL(
           this.changeNum, patchNum, '/' + action.__key)
           .then(url => action.__url = url);
-    },
+    }
 
     /**
      * Given a change action, return a display label that uses the appropriate
@@ -864,7 +886,7 @@
       }
       // Otherwise, just map the name to sentence case.
       return this._toSentenceCase(action.label);
-    },
+    }
 
     /**
      * Capitalize the first letter and lowecase all others.
@@ -874,16 +896,16 @@
     _toSentenceCase(s) {
       if (!s.length) { return ''; }
       return s[0].toUpperCase() + s.slice(1).toLowerCase();
-    },
+    }
 
     _computeLoadingLabel(action) {
       return ActionLoadingLabels[action] || 'Working...';
-    },
+    }
 
     _canSubmitChange() {
       return this.$.jsAPI.canSubmitChange(this.change,
           this._getRevision(this.change, this.latestPatchNum));
-    },
+    }
 
     _getRevision(change, patchNum) {
       for (const rev of Object.values(change.revisions)) {
@@ -892,19 +914,32 @@
         }
       }
       return null;
-    },
+    }
 
     _modifyRevertMsg() {
       return this.$.jsAPI.modifyRevertMsg(this.change,
           this.$.confirmRevertDialog.message, this.commitMessage);
-    },
+    }
 
     showRevertDialog() {
       this.$.confirmRevertDialog.populateRevertMessage(
           this.commitMessage, this.change.current_revision);
       this.$.confirmRevertDialog.message = this._modifyRevertMsg();
       this._showActionDialog(this.$.confirmRevertDialog);
-    },
+    }
+
+    _modifyRevertSubmissionMsg() {
+      return this.$.jsAPI.modifyRevertSubmissionMsg(this.change,
+          this.$.confirmRevertSubmissionDialog.message, this.commitMessage);
+    }
+
+    showRevertSubmissionDialog() {
+      this.$.confirmRevertSubmissionDialog.populateRevertSubmissionMessage(
+          this.commitMessage, this.change.current_revision);
+      this.$.confirmRevertSubmissionDialog.message =
+          this._modifyRevertSubmissionMsg();
+      this._showActionDialog(this.$.confirmRevertSubmissionDialog);
+    }
 
     _handleActionTap(e) {
       e.preventDefault();
@@ -922,7 +957,7 @@
       }
       const type = el.getAttribute('data-action-type');
       this._handleAction(type, key);
-    },
+    }
 
     _handleOveflowItemTap(e) {
       e.preventDefault();
@@ -934,7 +969,7 @@
         return;
       }
       this._handleAction(e.detail.action.__type, e.detail.action.__key);
-    },
+    }
 
     _handleAction(type, key) {
       this.$.reporting.reportInteraction(`${type}-${key}`);
@@ -948,7 +983,7 @@
         default:
           this._fireAction(this._prependSlash(key), this.actions[key], false);
       }
-    },
+    }
 
     _handleChangeAction(key) {
       let action;
@@ -956,6 +991,9 @@
         case ChangeActions.REVERT:
           this.showRevertDialog();
           break;
+        case ChangeActions.REVERT_SUBMISSION:
+          this.showRevertSubmissionDialog();
+          break;
         case ChangeActions.ABANDON:
           this._showActionDialog(this.$.confirmAbandonDialog);
           break;
@@ -996,7 +1034,7 @@
         default:
           this._fireAction(this._prependSlash(key), this.actions[key], false);
       }
-    },
+    }
 
     _handleRevisionAction(key) {
       switch (key) {
@@ -1018,11 +1056,11 @@
           this._fireAction(this._prependSlash(key),
               this.revisionActions[key], true);
       }
-    },
+    }
 
     _prependSlash(key) {
       return key === '/' ? key : `/${key}`;
-    },
+    }
 
     /**
      * _hasKnownChainState set to true true if hasParent is defined (can be
@@ -1030,25 +1068,25 @@
      */
     _computeChainState(hasParent) {
       this._hasKnownChainState = true;
-    },
+    }
 
     _calculateDisabled(action, hasKnownChainState) {
       if (action.__key === 'rebase' && hasKnownChainState === false) {
         return true;
       }
       return !action.enabled;
-    },
+    }
 
     _handleConfirmDialogCancel() {
       this._hideAllDialogs();
-    },
+    }
 
     _hideAllDialogs() {
       const dialogEls =
           Polymer.dom(this.root).querySelectorAll('.confirmDialog');
       for (const dialogEl of dialogEls) { dialogEl.hidden = true; }
       this.$.overlay.close();
-    },
+    }
 
     _handleRebaseConfirm(e) {
       const el = this.$.confirmRebase;
@@ -1056,15 +1094,15 @@
       this.$.overlay.close();
       el.hidden = true;
       this._fireAction('/rebase', this.revisionActions.rebase, true, payload);
-    },
+    }
 
     _handleCherrypickConfirm() {
       this._handleCherryPickRestApi(false);
-    },
+    }
 
     _handleCherrypickConflictConfirm() {
       this._handleCherryPickRestApi(true);
-    },
+    }
 
     _handleCherryPickRestApi(conflicts) {
       const el = this.$.confirmCherrypick;
@@ -1089,7 +1127,7 @@
             allow_conflicts: conflicts,
           }
       );
-    },
+    }
 
     _handleMoveConfirm() {
       const el = this.$.confirmMove;
@@ -1108,7 +1146,7 @@
             message: el.message,
           }
       );
-    },
+    }
 
     _handleRevertDialogConfirm() {
       const el = this.$.confirmRevertDialog;
@@ -1116,7 +1154,15 @@
       el.hidden = true;
       this._fireAction('/revert', this.actions.revert, false,
           {message: el.message});
-    },
+    }
+
+    _handleRevertSubmissionDialogConfirm() {
+      const el = this.$.confirmRevertSubmissionDialog;
+      this.$.overlay.close();
+      el.hidden = true;
+      this._fireAction('/revert_submission', this.actions.revert_submission,
+          false, {message: el.message});
+    }
 
     _handleAbandonDialogConfirm() {
       const el = this.$.confirmAbandonDialog;
@@ -1124,38 +1170,38 @@
       el.hidden = true;
       this._fireAction('/abandon', this.actions.abandon, false,
           {message: el.message});
-    },
+    }
 
     _handleCreateFollowUpChange() {
       this.$.createFollowUpChange.handleCreateChange();
       this._handleCloseCreateFollowUpChange();
-    },
+    }
 
     _handleCloseCreateFollowUpChange() {
       this.$.overlay.close();
-    },
+    }
 
     _handleDeleteConfirm() {
       this._fireAction('/', this.actions[ChangeActions.DELETE], false);
-    },
+    }
 
     _handleDeleteEditConfirm() {
       this._hideAllDialogs();
 
       this._fireAction('/edit', this.actions.deleteEdit, false);
-    },
+    }
 
     _handleSubmitConfirm() {
       if (!this._canSubmitChange()) { return; }
       this._hideAllDialogs();
       this._fireAction('/submit', this.revisionActions.submit, true);
-    },
+    }
 
     _getActionOverflowIndex(type, key) {
       return this._overflowActions.findIndex(action => {
         return action.type === type && action.key === key;
       });
-    },
+    }
 
     _setLoadingOnButtonWithKey(type, key) {
       this._actionLoadingMessage = this._computeLoadingLabel(key);
@@ -1178,7 +1224,7 @@
         buttonEl.removeAttribute('loading');
         buttonEl.disabled = false;
       }.bind(this);
-    },
+    }
 
     /**
      * @param {string} endpoint
@@ -1192,7 +1238,7 @@
 
       this._send(action.method, opt_payload, endpoint, revAction, cleanupFn,
           action).then(this._handleResponse.bind(this, action));
-    },
+    }
 
     _showActionDialog(dialog) {
       this._hideAllDialogs();
@@ -1203,7 +1249,7 @@
           dialog.resetFocus();
         }
       });
-    },
+    }
 
     // TODO(rmistry): Redo this after
     // https://bugs.chromium.org/p/gerrit/issues/detail?id=4671 is resolved.
@@ -1211,11 +1257,12 @@
       const labels = this.$.jsAPI.getLabelValuesPostRevert(this.change);
       if (!labels) { return Promise.resolve(); }
       return this.$.restAPI.saveChangeReview(newChangeId, 'current', {labels});
-    },
+    }
 
     _handleResponse(action, response) {
       if (!response) { return; }
       return this.$.restAPI.getResponseObject(response).then(obj => {
+        let revertChanges = [];
         switch (action.__key) {
           case ChangeActions.REVERT:
             this._waitForChangeReachable(obj._number)
@@ -1240,13 +1287,40 @@
           case ChangeActions.REBASE_EDIT:
             Gerrit.Nav.navigateToChange(this.change);
             break;
+          case ChangeActions.REVERT_SUBMISSION:
+            revertChanges = obj.revert_changes || [];
+            revertChanges = revertChanges.map(change => {
+              change.link = '/q/' + encodeURIComponent(change.change_id);
+              return change;
+            });
+            // list of reverted changes can never be 0
+            if (revertChanges.length === 1) {
+              // redirect to the change if only 1 change is reverted
+              const change = revertChanges[0];
+              this._waitForChangeReachable(change._number).then(success => {
+                if (success) {
+                  Gerrit.Nav.navigateToChange(change);
+                } else {
+                  console.error('Change ' + change._number + ' not reachable');
+                }
+              });
+            } else {
+              // show multiple reverted changes in a dialog
+              this._revertChanges = revertChanges;
+              this._showActionDialog(this.$.showRevertSubmissionChangesDialog);
+            }
+            break;
           default:
             this.dispatchEvent(new CustomEvent('reload-change',
                 {detail: {action: action.__key}, bubbles: false}));
             break;
         }
       });
-    },
+    }
+
+    _handleShowRevertSubmissionChangesConfirm() {
+      this._hideAllDialogs();
+    }
 
     _handleResponseError(action, response, body) {
       if (action && action.__key === RevisionActions.CHERRYPICK) {
@@ -1263,7 +1337,7 @@
           throw Error(errText);
         }
       });
-    },
+    }
 
     /**
      * @param {string} method
@@ -1306,58 +1380,58 @@
                   return response;
                 });
           });
-    },
+    }
 
     _handleAbandonTap() {
       this._showActionDialog(this.$.confirmAbandonDialog);
-    },
+    }
 
     _handleCherrypickTap() {
       this.$.confirmCherrypick.branch = '';
       this._showActionDialog(this.$.confirmCherrypick);
-    },
+    }
 
     _handleMoveTap() {
       this.$.confirmMove.branch = '';
       this.$.confirmMove.message = '';
       this._showActionDialog(this.$.confirmMove);
-    },
+    }
 
     _handleDownloadTap() {
       this.fire('download-tap', null, {bubbles: false});
-    },
+    }
 
     _handleDeleteTap() {
       this._showActionDialog(this.$.confirmDeleteDialog);
-    },
+    }
 
     _handleDeleteEditTap() {
       this._showActionDialog(this.$.confirmDeleteEditDialog);
-    },
+    }
 
     _handleFollowUpTap() {
       this._showActionDialog(this.$.createFollowUpDialog);
-    },
+    }
 
     _handleWipTap() {
       this._fireAction('/wip', this.actions.wip, false);
-    },
+    }
 
     _handlePublishEditTap() {
       this._fireAction('/edit:publish', this.actions.publishEdit, false);
-    },
+    }
 
     _handleRebaseEditTap() {
       this._fireAction('/edit:rebase', this.actions.rebaseEdit, false);
-    },
+    }
 
     _handleHideBackgroundContent() {
       this.$.mainContent.classList.add('overlayOpen');
-    },
+    }
 
     _handleShowBackgroundContent() {
       this.$.mainContent.classList.remove('overlayOpen');
-    },
+    }
 
     /**
      * Merge sources of change actions into a single ordered array of action
@@ -1400,7 +1474,7 @@
             }
             return action;
           });
-    },
+    }
 
     _getActionPriority(action) {
       if (action.__type && action.__key) {
@@ -1422,7 +1496,7 @@
         return ActionPriority.REVISION;
       }
       return ActionPriority.DEFAULT;
-    },
+    }
 
     /**
      * Sort comparator to define the order of change actions.
@@ -1436,7 +1510,7 @@
       } else {
         return priorityDelta;
       }
-    },
+    }
 
     _computeTopLevelActions(actionRecord, hiddenActionsRecord) {
       const hiddenActions = hiddenActionsRecord.base || [];
@@ -1444,14 +1518,14 @@
         const overflow = this._getActionOverflowIndex(a.__type, a.__key) !== -1;
         return !(overflow || hiddenActions.includes(a.__key));
       });
-    },
+    }
 
     _filterPrimaryActions(_topLevelActions) {
       this._topLevelPrimaryActions = _topLevelActions.filter(action =>
-          action.__primary);
+        action.__primary);
       this._topLevelSecondaryActions = _topLevelActions.filter(action =>
-          !action.__primary);
-    },
+        !action.__primary);
+    }
 
     _computeMenuActions(actionRecord, hiddenActionsRecord) {
       const hiddenActions = hiddenActionsRecord.base || [];
@@ -1468,7 +1542,7 @@
           tooltip: action.title,
         };
       });
-    },
+    }
 
     /**
      * Occasionally, a change created by a change action is not yet knwon to the
@@ -1502,22 +1576,24 @@
         };
         check();
       });
-    },
+    }
 
     _handleEditTap() {
       this.dispatchEvent(new CustomEvent('edit-tap', {bubbles: false}));
-    },
+    }
 
     _handleStopEditTap() {
       this.dispatchEvent(new CustomEvent('stop-edit-tap', {bubbles: false}));
-    },
+    }
 
     _computeHasTooltip(title) {
       return !!title;
-    },
+    }
 
     _computeHasIcon(action) {
       return action.icon ? '' : 'hidden';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeActions.is, GrChangeActions);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions_test.html b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions_test.html
index 37201ac..532c573 100644
--- a/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions_test.html
+++ b/polygerrit-ui/app/elements/change/gr-change-actions/gr-change-actions_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-actions</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -378,7 +378,7 @@
         element._handleRebaseConfirm({detail: {base: '1234'}});
         rebaseAction.rebaseOnCurrent = true;
         assert.deepEqual(fireActionStub.lastCall.args,
-          ['/rebase', rebaseAction, true, {base: '1234'}]);
+            ['/rebase', rebaseAction, true, {base: '1234'}]);
         done();
       });
     });
@@ -1060,7 +1060,6 @@
         element.reload().then(() => { flush(done); });
       });
 
-
       test('unignore button is not outside of the overflow menu', () => {
         assert.isNotOk(element.$$('[data-action-key="unignore"]'));
       });
@@ -1140,7 +1139,6 @@
         element.reload().then(() => { flush(done); });
       });
 
-
       test('unreviewed button not outside of the overflow menu', () => {
         assert.isNotOk(element.$$('[data-action-key="unreviewed"]'));
       });
@@ -1424,6 +1422,7 @@
       let payload;
       let onShowError;
       let onShowAlert;
+      let getResponseObjectStub;
 
       setup(() => {
         cleanup = sinon.stub();
@@ -1439,12 +1438,18 @@
 
       suite('happy path', () => {
         let sendStub;
-
+        let waitForChangeReachableStub;
         setup(() => {
           sandbox.stub(element, 'fetchChangeUpdates')
               .returns(Promise.resolve({isLatest: true}));
           sendStub = sandbox.stub(element.$.restAPI, 'executeChangeAction')
               .returns(Promise.resolve({}));
+          getResponseObjectStub = sandbox.stub(element.$.restAPI,
+              'getResponseObject');
+          waitForChangeReachableStub = sandbox.stub(element,
+              '_waitForChangeReachable').returns(Promise.resolve(true));
+          sandbox.stub(Gerrit.Nav,
+              'navigateToChange').returns(Promise.resolve(true));
         });
 
         test('change action', () => {
@@ -1457,6 +1462,49 @@
               });
         });
 
+        suite('single changes revert', () => {
+          setup(() => {
+            getResponseObjectStub
+                .returns(Promise.resolve({revert_changes: [
+                  {change_id: 12345},
+                ]}));
+            showActionDialogStub = sandbox.stub(element, '_showActionDialog');
+          });
+
+          test('revert submission single change', done => {
+            element._send('POST', {message: 'Revert submission'},
+                '/revert_submission', false, cleanup).then(res => {
+              element._handleResponse({__key: 'revert_submission'}, {}).
+                  then(() => {
+                    assert.isTrue(waitForChangeReachableStub.called);
+                    done();
+                  });
+            });
+          });
+        });
+
+        suite('multiple changes revert', () => {
+          let showActionDialogStub;
+          setup(() => {
+            getResponseObjectStub
+                .returns(Promise.resolve({revert_changes: [
+                  {change_id: 12345}, {change_id: 23456},
+                ]}));
+            showActionDialogStub = sandbox.stub(element, '_showActionDialog');
+          });
+
+          test('revert submission multiple change', done => {
+            element._send('POST', {message: 'Revert submission'},
+                '/revert_submission', false, cleanup).then(res => {
+              element._handleResponse({__key: 'revert_submission'}, {}).then(
+                  () => {
+                    assert.isTrue(showActionDialogStub.called);
+                    done();
+                  });
+            });
+          });
+        });
+
         test('revision action', () => {
           return element._send('DELETE', payload, '/endpoint', true, cleanup)
               .then(() => {
@@ -1541,7 +1589,6 @@
       element.changeNum = '42';
       element.latestPatchNum = '2';
 
-
       sandbox.stub(element.$.confirmCherrypick.$.restAPI,
           'getRepoBranches').returns(Promise.resolve([]));
       sandbox.stub(element.$.confirmMove.$.restAPI,
diff --git a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata-it_test.html b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata-it_test.html
index e60909c..8d85dce 100644
--- a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata-it_test.html
+++ b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata-it_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-metadata</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -114,7 +114,7 @@
             js_resource_paths: [],
             html_resource_paths: [
               new URL('test/plugin.html?' + Math.random(),
-                      window.location.href).toString(),
+                  window.location.href).toString(),
             ],
           },
         };
@@ -140,7 +140,7 @@
       setup(() => {
         Gerrit.install(p => plugin = p, '0.1',
             new URL('test/plugin.html?' + Math.random(),
-                    window.location.href).toString());
+                window.location.href).toString());
         sandbox.stub(Gerrit, '_arePluginsLoaded').returns(true);
         Gerrit._loadPlugins([]);
         element = createElement();
diff --git a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.html b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.html
index 6a92d96..539b1b6 100644
--- a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.html
+++ b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.html
@@ -43,7 +43,9 @@
 
 <dom-module id="gr-change-metadata">
   <template>
-    <style include="gr-change-metadata-shared-styles"></style>
+    <style include="gr-change-metadata-shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       :host {
         display: table;
@@ -175,9 +177,10 @@
         <span class="title">Assignee</span>
         <span class="value">
           <gr-account-list
-              max-count="1"
               id="assigneeValue"
               placeholder="Set assignee..."
+              max-count="1"
+              skip-suggest-on-empty
               accounts="{{_assignee}}"
               readonly="[[_computeAssigneeReadOnly(_mutable, change)]]"
               suggestions-provider="[[_getReviewerSuggestionsProvider(change)]]">
diff --git a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.js b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.js
index 07eb59e..e0d9676 100644
--- a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.js
+++ b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata.js
@@ -48,105 +48,111 @@
     TRUSTED: 'TRUSTED',
   };
 
-  Polymer({
-    is: 'gr-change-metadata',
-
+  /**
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrChangeMetadata extends Polymer.mixinBehaviors( [
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-metadata'; }
     /**
      * Fired when the change topic is changed.
      *
      * @event topic-changed
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      change: Object,
-      labels: {
-        type: Object,
-        notify: true,
-      },
-      account: Object,
-      /** @type {?} */
-      revision: Object,
-      commitInfo: Object,
-      _mutable: {
-        type: Boolean,
-        computed: '_computeIsMutable(account)',
-      },
-      /** @type {?} */
-      serverConfig: Object,
-      parentIsCurrent: Boolean,
-      _notCurrentMessage: {
-        type: String,
-        value: NOT_CURRENT_MESSAGE,
-        readOnly: true,
-      },
-      _topicReadOnly: {
-        type: Boolean,
-        computed: '_computeTopicReadOnly(_mutable, change)',
-      },
-      _hashtagReadOnly: {
-        type: Boolean,
-        computed: '_computeHashtagReadOnly(_mutable, change)',
-      },
-      /**
+        change: Object,
+        labels: {
+          type: Object,
+          notify: true,
+        },
+        account: Object,
+        /** @type {?} */
+        revision: Object,
+        commitInfo: Object,
+        _mutable: {
+          type: Boolean,
+          computed: '_computeIsMutable(account)',
+        },
+        /** @type {?} */
+        serverConfig: Object,
+        parentIsCurrent: Boolean,
+        _notCurrentMessage: {
+          type: String,
+          value: NOT_CURRENT_MESSAGE,
+          readOnly: true,
+        },
+        _topicReadOnly: {
+          type: Boolean,
+          computed: '_computeTopicReadOnly(_mutable, change)',
+        },
+        _hashtagReadOnly: {
+          type: Boolean,
+          computed: '_computeHashtagReadOnly(_mutable, change)',
+        },
+        /**
        * @type {Gerrit.PushCertificateValidation}
        */
-      _pushCertificateValidation: {
-        type: Object,
-        computed: '_computePushCertificateValidation(serverConfig, change)',
-      },
-      _showRequirements: {
-        type: Boolean,
-        computed: '_computeShowRequirements(change)',
-      },
-
-      _assignee: Array,
-      _isWip: {
-        type: Boolean,
-        computed: '_computeIsWip(change)',
-      },
-      _newHashtag: String,
-
-      _settingTopic: {
-        type: Boolean,
-        value: false,
-      },
-
-      _currentParents: {
-        type: Array,
-        computed: '_computeParents(change)',
-      },
-
-      /** @type {?} */
-      _CHANGE_ROLE: {
-        type: Object,
-        readOnly: true,
-        value: {
-          OWNER: 'owner',
-          UPLOADER: 'uploader',
-          AUTHOR: 'author',
-          COMMITTER: 'committer',
+        _pushCertificateValidation: {
+          type: Object,
+          computed: '_computePushCertificateValidation(serverConfig, change)',
         },
-      },
-    },
+        _showRequirements: {
+          type: Boolean,
+          computed: '_computeShowRequirements(change)',
+        },
 
-    behaviors: [
-      Gerrit.RESTClientBehavior,
-    ],
+        _assignee: Array,
+        _isWip: {
+          type: Boolean,
+          computed: '_computeIsWip(change)',
+        },
+        _newHashtag: String,
 
-    observers: [
-      '_changeChanged(change)',
-      '_labelsChanged(change.labels)',
-      '_assigneeChanged(_assignee.*)',
-    ],
+        _settingTopic: {
+          type: Boolean,
+          value: false,
+        },
+
+        _currentParents: {
+          type: Array,
+          computed: '_computeParents(change)',
+        },
+
+        /** @type {?} */
+        _CHANGE_ROLE: {
+          type: Object,
+          readOnly: true,
+          value: {
+            OWNER: 'owner',
+            UPLOADER: 'uploader',
+            AUTHOR: 'author',
+            COMMITTER: 'committer',
+          },
+        },
+      };
+    }
+
+    static get observers() {
+      return [
+        '_changeChanged(change)',
+        '_labelsChanged(change.labels)',
+        '_assigneeChanged(_assignee.*)',
+      ];
+    }
 
     _labelsChanged(labels) {
       this.labels = Object.assign({}, labels) || null;
-    },
+    }
 
     _changeChanged(change) {
       this._assignee = change.assignee ? [change.assignee] : [];
-    },
+    }
 
     _assigneeChanged(assigneeRecord) {
       if (!this.change) { return; }
@@ -162,11 +168,11 @@
         this.set(['change', 'assignee'], undefined);
         this.$.restAPI.deleteAssignee(this.change._number);
       }
-    },
+    }
 
     _computeHideStrategy(change) {
       return !this.changeIsOpen(change);
-    },
+    }
 
     /**
      * @param {Object} commitInfo
@@ -184,15 +190,15 @@
             config: serverConfig,
           });
       return weblinks.length ? weblinks : null;
-    },
+    }
 
     _computeStrategy(change) {
       return SubmitTypeLabel[change.submit_type];
-    },
+    }
 
     _computeLabelNames(labels) {
       return Object.keys(labels).sort();
-    },
+    }
 
     _handleTopicChanged(e, topic) {
       const lastTopic = this.change.topic;
@@ -207,19 +213,19 @@
                   'topic-changed', {bubbles: true, composed: true}));
             }
           });
-    },
+    }
 
     _showAddTopic(changeRecord, settingTopic) {
       const hasTopic = !!changeRecord &&
           !!changeRecord.base && !!changeRecord.base.topic;
       return !hasTopic && !settingTopic;
-    },
+    }
 
     _showTopicChip(changeRecord, settingTopic) {
       const hasTopic = !!changeRecord &&
           !!changeRecord.base && !!changeRecord.base.topic;
       return hasTopic && !settingTopic;
-    },
+    }
 
     _handleHashtagChanged(e) {
       const lastHashtag = this.change.hashtag;
@@ -228,13 +234,13 @@
       this._newHashtag = '';
       this.$.restAPI.setChangeHashtag(
           this.change._number, {add: [newHashtag]}).then(newHashtag => {
-            this.set(['change', 'hashtags'], newHashtag);
-            if (newHashtag !== lastHashtag) {
-              this.dispatchEvent(new CustomEvent(
-                  'hashtag-changed', {bubbles: true, composed: true}));
-            }
-          });
-    },
+        this.set(['change', 'hashtags'], newHashtag);
+        if (newHashtag !== lastHashtag) {
+          this.dispatchEvent(new CustomEvent(
+              'hashtag-changed', {bubbles: true, composed: true}));
+        }
+      });
+    }
 
     _computeTopicReadOnly(mutable, change) {
       return !mutable ||
@@ -242,7 +248,7 @@
           !change.actions ||
           !change.actions.topic ||
           !change.actions.topic.enabled;
-    },
+    }
 
     _computeHashtagReadOnly(mutable, change) {
       return !mutable ||
@@ -250,7 +256,7 @@
           !change.actions ||
           !change.actions.hashtags ||
           !change.actions.hashtags.enabled;
-    },
+    }
 
     _computeAssigneeReadOnly(mutable, change) {
       return !mutable ||
@@ -258,17 +264,17 @@
           !change.actions ||
           !change.actions.assignee ||
           !change.actions.assignee.enabled;
-    },
+    }
 
     _computeTopicPlaceholder(_topicReadOnly) {
       // Action items in Material Design are uppercase -- placeholder label text
       // is sentence case.
       return _topicReadOnly ? 'No topic' : 'ADD TOPIC';
-    },
+    }
 
     _computeHashtagPlaceholder(_hashtagReadOnly) {
       return _hashtagReadOnly ? '' : HASHTAG_ADD_MESSAGE;
-    },
+    }
 
     _computeShowRequirements(change) {
       if (change.status !== this.ChangeStatus.NEW) {
@@ -281,7 +287,7 @@
       const hasLabels = !!change.labels &&
           Object.keys(change.labels).length > 0;
       return hasRequirements || hasLabels || !!change.work_in_progress;
-    },
+    }
 
     /**
      * @return {?Gerrit.PushCertificateValidation} object representing data for
@@ -326,7 +332,7 @@
         default:
           throw new Error(`unknown certificate status: ${key.status}`);
       }
-    },
+    }
 
     _problems(msg, key) {
       if (!key || !key.problems || key.problems.length === 0) {
@@ -334,26 +340,26 @@
       }
 
       return [msg + ':'].concat(key.problems).join('\n');
-    },
+    }
 
     _computeProjectURL(project) {
       return Gerrit.Nav.getUrlForProjectChanges(project);
-    },
+    }
 
     _computeBranchURL(project, branch) {
       if (!this.change || !this.change.status) return '';
       return Gerrit.Nav.getUrlForBranch(branch, project,
           this.change.status == this.ChangeStatus.NEW ? 'open' :
-              this.change.status.toLowerCase());
-    },
+            this.change.status.toLowerCase());
+    }
 
     _computeTopicURL(topic) {
       return Gerrit.Nav.getUrlForTopic(topic);
-    },
+    }
 
     _computeHashtagURL(hashtag) {
       return Gerrit.Nav.getUrlForHashtag(hashtag);
-    },
+    }
 
     _handleTopicRemoved(e) {
       const target = Polymer.dom(e).rootTarget;
@@ -367,7 +373,7 @@
         target.disabled = false;
         return;
       });
-    },
+    }
 
     _handleHashtagRemoved(e) {
       e.preventDefault();
@@ -382,15 +388,15 @@
             target.disabled = false;
             return;
           });
-    },
+    }
 
     _computeIsWip(change) {
       return !!change.work_in_progress;
-    },
+    }
 
     _computeShowRoleClass(change, role) {
       return this._getNonOwnerRole(change, role) ? '' : 'hideDisplay';
-    },
+    }
 
     /**
      * Get the user with the specified role on the change. Returns null if the
@@ -427,7 +433,7 @@
       }
 
       return null;
-    },
+    }
 
     _computeParents(change) {
       if (!change || !change.current_revision ||
@@ -436,11 +442,11 @@
         return undefined;
       }
       return change.revisions[change.current_revision].commit.parents;
-    },
+    }
 
     _computeParentsLabel(parents) {
       return parents && parents.length > 1 ? 'Parents' : 'Parent';
-    },
+    }
 
     _computeParentListClass(parents, parentIsCurrent) {
       // Undefined check for polymer 2
@@ -453,24 +459,26 @@
         parents && parents.length > 1 ? 'merge' : 'nonMerge',
         parentIsCurrent ? 'current' : 'notCurrent',
       ].join(' ');
-    },
+    }
 
     _computeIsMutable(account) {
       return !!Object.keys(account).length;
-    },
+    }
 
     editTopic() {
       if (this._topicReadOnly || this.change.topic) { return; }
       // Cannot use `this.$.ID` syntax because the element exists inside of a
       // dom-if.
       this.$$('.topicEditableLabel').open();
-    },
+    }
 
     _getReviewerSuggestionsProvider(change) {
       const provider = GrReviewerSuggestionsProvider.create(this.$.restAPI,
           change._number, Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.ANY);
       provider.init();
       return provider;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeMetadata.is, GrChangeMetadata);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata_test.html b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata_test.html
index caa38d9..148d917 100644
--- a/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata_test.html
+++ b/polygerrit-ui/app/elements/change/gr-change-metadata/gr-change-metadata_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-metadata</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -426,7 +426,7 @@
           {current_revision: '789', revisions: {456: {commit: {parents}}}}));
       assert.equal(element._computeParents(
           {current_revision: '456', revisions: {456: {commit: {parents}}}}),
-          parents);
+      parents);
     });
 
     test('_computeParentsLabel', () => {
diff --git a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements.js b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements.js
index 8ec00dd..2e0332b 100644
--- a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements.js
+++ b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements.js
@@ -17,47 +17,54 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-change-requirements',
+  /**
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrChangeRequirements extends Polymer.mixinBehaviors( [
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-requirements'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      change: Object,
-      account: Object,
-      mutable: Boolean,
-      _requirements: {
-        type: Array,
-        computed: '_computeRequirements(change)',
-      },
-      _requiredLabels: {
-        type: Array,
-        value: () => [],
-      },
-      _optionalLabels: {
-        type: Array,
-        value: () => [],
-      },
-      _showWip: {
-        type: Boolean,
-        computed: '_computeShowWip(change)',
-      },
-      _showOptionalLabels: {
-        type: Boolean,
-        value: true,
-      },
-    },
+        change: Object,
+        account: Object,
+        mutable: Boolean,
+        _requirements: {
+          type: Array,
+          computed: '_computeRequirements(change)',
+        },
+        _requiredLabels: {
+          type: Array,
+          value: () => [],
+        },
+        _optionalLabels: {
+          type: Array,
+          value: () => [],
+        },
+        _showWip: {
+          type: Boolean,
+          computed: '_computeShowWip(change)',
+        },
+        _showOptionalLabels: {
+          type: Boolean,
+          value: true,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.RESTClientBehavior,
-    ],
-
-    observers: [
-      '_computeLabels(change.labels.*)',
-    ],
+    static get observers() {
+      return [
+        '_computeLabels(change.labels.*)',
+      ];
+    }
 
     _computeShowWip(change) {
       return change.work_in_progress;
-    },
+    }
 
     _computeRequirements(change) {
       const _requirements = [];
@@ -78,15 +85,15 @@
       }
 
       return _requirements;
-    },
+    }
 
     _computeRequirementClass(requirementStatus) {
       return requirementStatus ? 'approved' : '';
-    },
+    }
 
     _computeRequirementIcon(requirementStatus) {
       return requirementStatus ? 'gr-icons:check' : 'gr-icons:hourglass';
-    },
+    }
 
     _computeLabels(labelsRecord) {
       const labels = labelsRecord.base;
@@ -103,7 +110,7 @@
 
         this.push(path, {label, icon, style, labelInfo});
       }
-    },
+    }
 
     /**
      * @param {Object} labelInfo
@@ -114,7 +121,7 @@
       if (labelInfo.approved) { return 'gr-icons:check'; }
       if (labelInfo.rejected) { return 'gr-icons:close'; }
       return 'gr-icons:hourglass';
-    },
+    }
 
     /**
      * @param {Object} labelInfo
@@ -123,28 +130,30 @@
       if (labelInfo.approved) { return 'approved'; }
       if (labelInfo.rejected) { return 'rejected'; }
       return '';
-    },
+    }
 
     _computeShowOptional(optionalFieldsRecord) {
       return optionalFieldsRecord.base.length ? '' : 'hidden';
-    },
+    }
 
     _computeLabelValue(value) {
       return (value > 0 ? '+' : '') + value;
-    },
+    }
 
     _computeShowHideIcon(showOptionalLabels) {
       return showOptionalLabels ?
-          'gr-icons:expand-less' :
-          'gr-icons:expand-more';
-    },
+        'gr-icons:expand-less' :
+        'gr-icons:expand-more';
+    }
 
     _computeSectionClass(show) {
       return show ? '' : 'hidden';
-    },
+    }
 
     _handleShowHide(e) {
       this._showOptionalLabels = !this._showOptionalLabels;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeRequirements.is, GrChangeRequirements);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_test.html b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_test.html
index 2ceac39..242fe2c 100644
--- a/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_test.html
+++ b/polygerrit-ui/app/elements/change/gr-change-requirements/gr-change-requirements_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-requirements</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.html b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.html
index 45df471..b86213a 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.html
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.html
@@ -408,8 +408,6 @@
               change-status="[[_change.status]]"
               commit-num="[[_commitInfo.commit]]"
               latest-patch-num="[[computeLatestPatchNum(_allPatchSets)]]"
-              reply-disabled="[[_replyDisabled]]"
-              reply-button-label="[[_replyButtonLabel]]"
               commit-message="[[_latestCommitMessage]]"
               edit-patchset-loaded="[[hasEditPatchsetLoaded(_patchRange.*)]]"
               edit-mode="[[_editMode]]"
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.js b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.js
index e6ceea2..5de378b 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.js
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view.js
@@ -63,9 +63,21 @@
   const CHANGE_RELOAD_TIMING_LABEL = 'ChangeReloaded';
   const SEND_REPLY_TIMING_LABEL = 'SendReply';
 
-  Polymer({
-    is: 'gr-change-view',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrChangeView extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-view'; }
     /**
      * Fired when the title of the page should change.
      *
@@ -84,230 +96,215 @@
      * @event show-auth-required
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
-      /** @type {?} */
-      viewState: {
-        type: Object,
-        notify: true,
-        value() { return {}; },
-        observer: '_viewStateChanged',
-      },
-      backPage: String,
-      hasParent: Boolean,
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      disableEdit: {
-        type: Boolean,
-        value: false,
-      },
-      disableDiffPrefs: {
-        type: Boolean,
-        value: false,
-      },
-      _diffPrefsDisabled: {
-        type: Boolean,
-        computed: '_computeDiffPrefsDisabled(disableDiffPrefs, _loggedIn)',
-      },
-      _commentThreads: Array,
-      /** @type {?} */
-      _serverConfig: {
-        type: Object,
-        observer: '_startUpdateCheckTimer',
-      },
-      _diffPrefs: Object,
-      _numFilesShown: {
-        type: Number,
-        value: DEFAULT_NUM_FILES_SHOWN,
-        observer: '_numFilesShownChanged',
-      },
-      _account: {
-        type: Object,
-        value: {},
-      },
-      _prefs: Object,
-      /** @type {?} */
-      _changeComments: Object,
-      _canStartReview: {
-        type: Boolean,
-        computed: '_computeCanStartReview(_change)',
-      },
-      _comments: Object,
-      /** @type {?} */
-      _change: {
-        type: Object,
-        observer: '_changeChanged',
-      },
-      _revisionInfo: {
-        type: Object,
-        computed: '_getRevisionInfo(_change)',
-      },
-      /** @type {?} */
-      _commitInfo: Object,
-      _currentRevision: {
-        type: Object,
-        computed: '_computeCurrentRevision(_change.current_revision, ' +
-            '_change.revisions)',
-      },
-      _files: Object,
-      _changeNum: String,
-      _diffDrafts: {
-        type: Object,
-        value() { return {}; },
-      },
-      _editingCommitMessage: {
-        type: Boolean,
-        value: false,
-      },
-      _hideEditCommitMessage: {
-        type: Boolean,
-        computed: '_computeHideEditCommitMessage(_loggedIn, ' +
-            '_editingCommitMessage, _change, _editMode)',
-      },
-      _diffAgainst: String,
-      /** @type {?string} */
-      _latestCommitMessage: {
-        type: String,
-        value: '',
-      },
-      _lineHeight: Number,
-      _changeIdCommitMessageError: {
-        type: String,
-        computed:
-          '_computeChangeIdCommitMessageError(_latestCommitMessage, _change)',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
         /** @type {?} */
-      _patchRange: {
-        type: Object,
-      },
-      _filesExpanded: String,
-      _basePatchNum: String,
-      _selectedRevision: Object,
-      _currentRevisionActions: Object,
-      _allPatchSets: {
-        type: Array,
-        computed: 'computeAllPatchSets(_change, _change.revisions.*)',
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-      _loading: Boolean,
-      /** @type {?} */
-      _projectConfig: Object,
-      _rebaseOnCurrent: Boolean,
-      _replyButtonLabel: {
-        type: String,
-        value: 'Reply',
-        computed: '_computeReplyButtonLabel(_diffDrafts.*, _canStartReview)',
-      },
-      _selectedPatchSet: String,
-      _shownFileCount: Number,
-      _initialLoadComplete: {
-        type: Boolean,
-        value: false,
-      },
-      _replyDisabled: {
-        type: Boolean,
-        value: true,
-        computed: '_computeReplyDisabled(_serverConfig)',
-      },
-      _changeStatus: {
-        type: String,
-        computed: 'changeStatusString(_change)',
-      },
-      _changeStatuses: {
-        type: String,
-        computed:
+        viewState: {
+          type: Object,
+          notify: true,
+          value() { return {}; },
+          observer: '_viewStateChanged',
+        },
+        backPage: String,
+        hasParent: Boolean,
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
+        disableEdit: {
+          type: Boolean,
+          value: false,
+        },
+        disableDiffPrefs: {
+          type: Boolean,
+          value: false,
+        },
+        _diffPrefsDisabled: {
+          type: Boolean,
+          computed: '_computeDiffPrefsDisabled(disableDiffPrefs, _loggedIn)',
+        },
+        _commentThreads: Array,
+        /** @type {?} */
+        _serverConfig: {
+          type: Object,
+          observer: '_startUpdateCheckTimer',
+        },
+        _diffPrefs: Object,
+        _numFilesShown: {
+          type: Number,
+          value: DEFAULT_NUM_FILES_SHOWN,
+          observer: '_numFilesShownChanged',
+        },
+        _account: {
+          type: Object,
+          value: {},
+        },
+        _prefs: Object,
+        /** @type {?} */
+        _changeComments: Object,
+        _canStartReview: {
+          type: Boolean,
+          computed: '_computeCanStartReview(_change)',
+        },
+        _comments: Object,
+        /** @type {?} */
+        _change: {
+          type: Object,
+          observer: '_changeChanged',
+        },
+        _revisionInfo: {
+          type: Object,
+          computed: '_getRevisionInfo(_change)',
+        },
+        /** @type {?} */
+        _commitInfo: Object,
+        _currentRevision: {
+          type: Object,
+          computed: '_computeCurrentRevision(_change.current_revision, ' +
+            '_change.revisions)',
+        },
+        _files: Object,
+        _changeNum: String,
+        _diffDrafts: {
+          type: Object,
+          value() { return {}; },
+        },
+        _editingCommitMessage: {
+          type: Boolean,
+          value: false,
+        },
+        _hideEditCommitMessage: {
+          type: Boolean,
+          computed: '_computeHideEditCommitMessage(_loggedIn, ' +
+            '_editingCommitMessage, _change, _editMode)',
+        },
+        _diffAgainst: String,
+        /** @type {?string} */
+        _latestCommitMessage: {
+          type: String,
+          value: '',
+        },
+        _lineHeight: Number,
+        _changeIdCommitMessageError: {
+          type: String,
+          computed:
+          '_computeChangeIdCommitMessageError(_latestCommitMessage, _change)',
+        },
+        /** @type {?} */
+        _patchRange: {
+          type: Object,
+        },
+        _filesExpanded: String,
+        _basePatchNum: String,
+        _selectedRevision: Object,
+        _currentRevisionActions: Object,
+        _allPatchSets: {
+          type: Array,
+          computed: 'computeAllPatchSets(_change, _change.revisions.*)',
+        },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+        _loading: Boolean,
+        /** @type {?} */
+        _projectConfig: Object,
+        _rebaseOnCurrent: Boolean,
+        _replyButtonLabel: {
+          type: String,
+          value: 'Reply',
+          computed: '_computeReplyButtonLabel(_diffDrafts.*, _canStartReview)',
+        },
+        _selectedPatchSet: String,
+        _shownFileCount: Number,
+        _initialLoadComplete: {
+          type: Boolean,
+          value: false,
+        },
+        _replyDisabled: {
+          type: Boolean,
+          value: true,
+          computed: '_computeReplyDisabled(_serverConfig)',
+        },
+        _changeStatus: {
+          type: String,
+          computed: 'changeStatusString(_change)',
+        },
+        _changeStatuses: {
+          type: String,
+          computed:
           '_computeChangeStatusChips(_change, _mergeable, _submitEnabled)',
-      },
-      _commitCollapsed: {
-        type: Boolean,
-        value: true,
-      },
-      _relatedChangesCollapsed: {
-        type: Boolean,
-        value: true,
-      },
-      /** @type {?number} */
-      _updateCheckTimerHandle: Number,
-      _editMode: {
-        type: Boolean,
-        computed: '_computeEditMode(_patchRange.*, params.*)',
-      },
-      _showRelatedToggle: {
-        type: Boolean,
-        value: false,
-        observer: '_updateToggleContainerClass',
-      },
-      _parentIsCurrent: Boolean,
-      _submitEnabled: {
-        type: Boolean,
-        computed: '_isSubmitEnabled(_currentRevisionActions)',
-      },
+        },
+        _commitCollapsed: {
+          type: Boolean,
+          value: true,
+        },
+        _relatedChangesCollapsed: {
+          type: Boolean,
+          value: true,
+        },
+        /** @type {?number} */
+        _updateCheckTimerHandle: Number,
+        _editMode: {
+          type: Boolean,
+          computed: '_computeEditMode(_patchRange.*, params.*)',
+        },
+        _showRelatedToggle: {
+          type: Boolean,
+          value: false,
+          observer: '_updateToggleContainerClass',
+        },
+        _parentIsCurrent: Boolean,
+        _submitEnabled: {
+          type: Boolean,
+          computed: '_isSubmitEnabled(_currentRevisionActions)',
+        },
 
-      /** @type {?} */
-      _mergeable: {
-        type: Boolean,
-        value: undefined,
-      },
-      _showMessagesView: {
-        type: Boolean,
-        value: true,
-      },
-      _showFileTabContent: {
-        type: Boolean,
-        value: true,
-      },
-      /** @type {Array<string>} */
-      _dynamicTabHeaderEndpoints: {
-        type: Array,
-      },
-      _showPrimaryTabs: {
-        type: Boolean,
-        computed: '_computeShowPrimaryTabs(_dynamicTabHeaderEndpoints)',
-      },
-      /** @type {Array<string>} */
-      _dynamicTabContentEndpoints: {
-        type: Array,
-      },
-      _selectedFilesTabPluginEndpoint: {
-        type: String,
-      },
-    },
+        /** @type {?} */
+        _mergeable: {
+          type: Boolean,
+          value: undefined,
+        },
+        _showMessagesView: {
+          type: Boolean,
+          value: true,
+        },
+        _showFileTabContent: {
+          type: Boolean,
+          value: true,
+        },
+        /** @type {Array<string>} */
+        _dynamicTabHeaderEndpoints: {
+          type: Array,
+        },
+        _showPrimaryTabs: {
+          type: Boolean,
+          computed: '_computeShowPrimaryTabs(_dynamicTabHeaderEndpoints)',
+        },
+        /** @type {Array<string>} */
+        _dynamicTabContentEndpoints: {
+          type: Array,
+        },
+        _selectedFilesTabPluginEndpoint: {
+          type: String,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
-
-    listeners: {
-      'topic-changed': '_handleTopicChanged',
-      // When an overlay is opened in a mobile viewport, the overlay has a full
-      // screen view. When it has a full screen view, we do not want the
-      // background to be scrollable. This will eliminate background scroll by
-      // hiding most of the contents on the screen upon opening, and showing
-      // again upon closing.
-      'fullscreen-overlay-opened': '_handleHideBackgroundContent',
-      'fullscreen-overlay-closed': '_handleShowBackgroundContent',
-      'diff-comments-modified': '_handleReloadCommentThreads',
-    },
-
-    observers: [
-      '_labelsChanged(_change.labels.*)',
-      '_paramsAndChangeChanged(params, _change)',
-      '_patchNumChanged(_patchRange.patchNum)',
-    ],
+    static get observers() {
+      return [
+        '_labelsChanged(_change.labels.*)',
+        '_paramsAndChangeChanged(params, _change)',
+        '_patchNumChanged(_patchRange.patchNum)',
+      ];
+    }
 
     keyboardShortcuts() {
       return {
@@ -325,9 +322,32 @@
         [this.Shortcut.OPEN_DIFF_PREFS]: '_handleOpenDiffPrefsShortcut',
         [this.Shortcut.EDIT_TOPIC]: '_handleEditTopic',
       };
-    },
+    }
+
+    created() {
+      super.created();
+
+      this.addEventListener('topic-changed',
+          () => this._handleTopicChanged());
+
+      this.addEventListener(
+          // When an overlay is opened in a mobile viewport, the overlay has a full
+          // screen view. When it has a full screen view, we do not want the
+          // background to be scrollable. This will eliminate background scroll by
+          // hiding most of the contents on the screen upon opening, and showing
+          // again upon closing.
+          'fullscreen-overlay-opened',
+          () => this._handleHideBackgroundContent());
+
+      this.addEventListener('fullscreen-overlay-closed',
+          () => this._handleShowBackgroundContent());
+
+      this.addEventListener('diff-comments-modified',
+          () => this._handleReloadCommentThreads());
+    }
 
     attached() {
+      super.attached();
       this._getServerConfig().then(config => {
         this._serverConfig = config;
       });
@@ -363,24 +383,25 @@
           this._handleCommitMessageCancel.bind(this));
       this.listen(window, 'scroll', '_handleScroll');
       this.listen(document, 'visibilitychange', '_handleVisibilityChange');
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'scroll', '_handleScroll');
       this.unlisten(document, 'visibilitychange', '_handleVisibilityChange');
 
       if (this._updateCheckTimerHandle) {
         this._cancelUpdateCheckTimer();
       }
-    },
+    }
 
     get messagesList() {
       return this.$$('gr-messages-list');
-    },
+    }
 
     get threadList() {
       return this.$$('gr-thread-list');
-    },
+    }
 
     /**
      * @param {boolean=} opt_reset
@@ -397,7 +418,7 @@
           this.set('viewState.diffMode', 'SIDE_BY_SIDE');
         }
       });
-    },
+    }
 
     _handleToggleDiffMode(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -409,11 +430,11 @@
       } else {
         this.$.fileListHeader.setDiffViewMode(DiffViewMode.SIDE_BY_SIDE);
       }
-    },
+    }
 
     _handleCommentTabChange() {
       this._showMessagesView = this.$.commentTabs.selected === 0;
-    },
+    }
 
     _handleFileTabChange(e) {
       const selectedIndex = this.$$('#primaryTabs').selected;
@@ -429,7 +450,7 @@
         this.$.reporting.reportInteraction('tab-changed',
             `tabname: ${tabName}, source: ${source}`);
       }
-    },
+    }
 
     _handleShowTab(e) {
       const idx = this._dynamicTabContentEndpoints.indexOf(e.detail.tab);
@@ -440,12 +461,12 @@
       this.$$('#primaryTabs').selected = idx + 1;
       this.$$('#primaryTabs').scrollIntoView();
       this.$.reporting.reportInteraction('show-tab', e.detail.tab);
-    },
+    }
 
     _handleEditCommitMessage(e) {
       this._editingCommitMessage = true;
       this.$.commitMessageEditor.focusTextarea();
-    },
+    }
 
     _handleCommitMessageSave(e) {
       // Trim trailing whitespace from each line.
@@ -456,25 +477,25 @@
       this.$.commitMessageEditor.disabled = true;
       this.$.restAPI.putChangeCommitMessage(
           this._changeNum, message).then(resp => {
-            this.$.commitMessageEditor.disabled = false;
-            if (!resp.ok) { return; }
+        this.$.commitMessageEditor.disabled = false;
+        if (!resp.ok) { return; }
 
-            this._latestCommitMessage = this._prepareCommitMsgForLinkify(
-                message);
-            this._editingCommitMessage = false;
-            this._reloadWindow();
-          }).catch(err => {
-            this.$.commitMessageEditor.disabled = false;
-          });
-    },
+        this._latestCommitMessage = this._prepareCommitMsgForLinkify(
+            message);
+        this._editingCommitMessage = false;
+        this._reloadWindow();
+      }).catch(err => {
+        this.$.commitMessageEditor.disabled = false;
+      });
+    }
 
     _reloadWindow() {
       window.location.reload();
-    },
+    }
 
     _handleCommitMessageCancel(e) {
       this._editingCommitMessage = false;
-    },
+    }
 
     _computeChangeStatusChips(change, mergeable, submitEnabled) {
       // Polymer 2: check for undefined
@@ -498,7 +519,7 @@
         submitEnabled: !!submitEnabled,
       };
       return this.changeStatuses(change, options);
-    },
+    }
 
     _computeHideEditCommitMessage(loggedIn, editing, change, editMode) {
       if (!loggedIn || editing ||
@@ -508,7 +529,7 @@
       }
 
       return false;
-    },
+    }
 
     _handleReloadCommentThreads() {
       // Get any new drafts that have been saved in the diff view and show
@@ -518,7 +539,7 @@
             .map(c => Object.assign({}, c));
         Polymer.dom.flush();
       });
-    },
+    }
 
     _handleReloadDiffComments(e) {
       // Keeps the file list counts updated.
@@ -529,7 +550,7 @@
             e.detail.path);
         Polymer.dom.flush();
       });
-    },
+    }
 
     _computeTotalCommentCounts(unresolvedCount, changeComments) {
       if (!changeComments) return undefined;
@@ -543,7 +564,7 @@
           // Add a comma and space if both unresolved and draft comments exist.
           (unresolvedString && draftString ? ', ' : '') +
           draftString;
-    },
+    }
 
     _handleCommentSave(e) {
       const draft = e.detail.comment;
@@ -575,7 +596,7 @@
         return (c1.line || -1) - (c2.line || -1);
       });
       this._diffDrafts = diffDrafts;
-    },
+    }
 
     _handleCommentDiscard(e) {
       const draft = e.detail.comment;
@@ -609,16 +630,16 @@
         delete diffDrafts[draft.path];
       }
       this._diffDrafts = diffDrafts;
-    },
+    }
 
     _handleReplyTap(e) {
       e.preventDefault();
       this._openReplyDialog(this.$.replyDialog.FocusTarget.ANY);
-    },
+    }
 
     _handleOpenDiffPrefs() {
       this.$.fileList.openDiffPrefs();
-    },
+    }
 
     _handleOpenIncludedInDialog() {
       this.$.includedInDialog.loadData().then(() => {
@@ -626,11 +647,11 @@
         this.$.includedInOverlay.refit();
       });
       this.$.includedInOverlay.open();
-    },
+    }
 
     _handleIncludedInDialogClose(e) {
       this.$.includedInOverlay.close();
-    },
+    }
 
     _handleOpenDownloadDialog() {
       this.$.downloadOverlay.open().then(() => {
@@ -638,19 +659,19 @@
             .setFocusStops(this.$.downloadDialog.getFocusStops());
         this.$.downloadDialog.focus();
       });
-    },
+    }
 
     _handleDownloadDialogClose(e) {
       this.$.downloadOverlay.close();
-    },
+    }
 
     _handleOpenUploadHelpDialog(e) {
       this.$.uploadHelpOverlay.open();
-    },
+    }
 
     _handleCloseUploadHelpDialog(e) {
       this.$.uploadHelpOverlay.close();
-    },
+    }
 
     _handleMessageReply(e) {
       const msg = e.detail.message.message;
@@ -658,33 +679,33 @@
           line => { return '> ' + line; }).join('\n') + '\n\n';
       this.$.replyDialog.quote = quoteStr;
       this._openReplyDialog(this.$.replyDialog.FocusTarget.BODY);
-    },
+    }
 
     _handleHideBackgroundContent() {
       this.$.mainContent.classList.add('overlayOpen');
-    },
+    }
 
     _handleShowBackgroundContent() {
       this.$.mainContent.classList.remove('overlayOpen');
-    },
+    }
 
     _handleReplySent(e) {
       this.$.replyOverlay.close();
       this._reload().then(() => {
         this.$.reporting.timeEnd(SEND_REPLY_TIMING_LABEL);
       });
-    },
+    }
 
     _handleReplyCancel(e) {
       this.$.replyOverlay.close();
-    },
+    }
 
     _handleReplyAutogrow(e) {
       // If the textarea resizes, we need to re-fit the overlay.
       this.debounce('reply-overlay-refit', () => {
         this.$.replyOverlay.refit();
       }, REPLY_REFIT_DEBOUNCE_INTERVAL_MS);
-    },
+    }
 
     _handleShowReplyDialog(e) {
       let target = this.$.replyDialog.FocusTarget.REVIEWERS;
@@ -692,25 +713,25 @@
         target = this.$.replyDialog.FocusTarget.CCS;
       }
       this._openReplyDialog(target);
-    },
+    }
 
     _handleScroll() {
       this.debounce('scroll', () => {
         this.viewState.scrollTop = document.body.scrollTop;
       }, 150);
-    },
+    }
 
     _setShownFiles(e) {
       this._shownFileCount = e.detail.length;
-    },
+    }
 
     _expandAllDiffs() {
       this.$.fileList.expandAllDiffs();
-    },
+    }
 
     _collapseAllDiffs() {
       this.$.fileList.collapseAllDiffs();
-    },
+    }
 
     _paramsChanged(value) {
       // Change the content of the comment tabs back to messages list, but
@@ -764,7 +785,7 @@
       this._reload(true).then(() => {
         this._performPostLoadTasks();
       });
-    },
+    }
 
     _sendShowChangeEvent() {
       this.$.jsAPI.handleEvent(this.$.jsAPI.EventType.SHOW_CHANGE, {
@@ -772,7 +793,7 @@
         patchNum: this._patchRange.patchNum,
         info: {mergeable: this._mergeable},
       });
-    },
+    }
 
     _setPrimaryTab() {
       // Selected has to be set after the paper-tabs are visible because
@@ -780,7 +801,7 @@
       this.$.commentTabs.selected = 0;
       const primaryTabs = this.$$('#primaryTabs');
       if (primaryTabs) primaryTabs.selected = 0;
-    },
+    }
 
     _performPostLoadTasks() {
       this._maybeShowReplyDialog();
@@ -799,7 +820,7 @@
         }
         this._initialLoadComplete = true;
       });
-    },
+    }
 
     _paramsAndChangeChanged(value, change) {
       // Polymer 2: check for undefined
@@ -815,16 +836,16 @@
           patchRangeState.patchNum !== this._patchRange.patchNum) {
         this._resetFileListViewState();
       }
-    },
+    }
 
     _viewStateChanged(viewState) {
       this._numFilesShown = viewState.numFilesShown ?
-          viewState.numFilesShown : DEFAULT_NUM_FILES_SHOWN;
-    },
+        viewState.numFilesShown : DEFAULT_NUM_FILES_SHOWN;
+    }
 
     _numFilesShownChanged(numFilesShown) {
       this.viewState.numFilesShown = numFilesShown;
-    },
+    }
 
     _handleMessageAnchorTap(e) {
       const hash = MSG_PREFIX + e.detail.id;
@@ -832,18 +853,18 @@
           this._patchRange.patchNum, this._patchRange.basePatchNum,
           this._editMode, hash);
       history.replaceState(null, '', url);
-    },
+    }
 
     _maybeScrollToMessage(hash) {
       if (hash.startsWith(MSG_PREFIX)) {
         this.messagesList.scrollToMessage(hash.substr(MSG_PREFIX.length));
       }
-    },
+    }
 
     _getLocationSearch() {
       // Not inlining to make it easier to test.
       return window.location.search;
-    },
+    }
 
     _getUrlParameter(param) {
       const pageURL = this._getLocationSearch().substring(1);
@@ -855,7 +876,7 @@
         }
       }
       return null;
-    },
+    }
 
     _maybeShowRevertDialog() {
       Gerrit.awaitPluginsLoaded()
@@ -871,7 +892,7 @@
               this.$.actions.showRevertDialog();
             }
           });
-    },
+    }
 
     _maybeShowReplyDialog() {
       this._getLoggedIn().then(loggedIn => {
@@ -885,7 +906,7 @@
           this.set('viewState.showReplyDialog', false);
         }
       });
-    },
+    }
 
     _resetFileListViewState() {
       this.set('viewState.selectedFileIndex', 0);
@@ -899,7 +920,7 @@
       }
       this.set('viewState.changeNum', this._changeNum);
       this.set('viewState.patchRange', this._patchRange);
-    },
+    }
 
     _changeChanged(change) {
       if (!change || !this._patchRange || !this._allPatchSets) { return; }
@@ -915,7 +936,7 @@
 
       const title = change.subject + ' (' + change.change_id.substr(0, 9) + ')';
       this.fire('title-change', {title});
-    },
+    }
 
     /**
      * Gets base patch number, if it is a parent try and decide from
@@ -937,7 +958,7 @@
       // check that there is at least 2 parents otherwise fall back to 1,
       // which means there is only one parent.
       const parentCount = parentCounts.hasOwnProperty(1) ?
-          parentCounts[1] : 1;
+        parentCounts[1] : 1;
 
       const preferFirst = this._prefs &&
           this._prefs.default_base_for_merges === 'FIRST_PARENT';
@@ -947,19 +968,19 @@
       }
 
       return 'PARENT';
-    },
+    }
 
     _computeShowPrimaryTabs(dynamicTabHeaderEndpoints) {
       return dynamicTabHeaderEndpoints && dynamicTabHeaderEndpoints.length > 0;
-    },
+    }
 
     _computeChangeUrl(change) {
       return Gerrit.Nav.getUrlForChange(change);
-    },
+    }
 
     _computeShowCommitInfo(changeStatus, current_revision) {
       return changeStatus === 'Merged' && current_revision;
-    },
+    }
 
     _computeMergedCommitInfo(current_revision, revisions) {
       const rev = revisions[current_revision];
@@ -968,11 +989,11 @@
       // in <gr-commit-info>. @see Issue 5337
       if (!rev.commit.commit) { rev.commit.commit = current_revision; }
       return rev.commit;
-    },
+    }
 
     _computeChangeIdClass(displayChangeId) {
       return displayChangeId === CHANGE_ID_ERROR.MISMATCH ? 'warning' : '';
-    },
+    }
 
     _computeTitleAttributeWarning(displayChangeId) {
       if (displayChangeId === CHANGE_ID_ERROR.MISMATCH) {
@@ -980,7 +1001,7 @@
       } else if (displayChangeId === CHANGE_ID_ERROR.MISSING) {
         return 'No Change-Id in commit message';
       }
-    },
+    }
 
     _computeChangeIdCommitMessageError(commitMessage, change) {
       // Polymer 2: check for undefined
@@ -1010,11 +1031,11 @@
       }
       // There is no change-id in the commit message.
       return CHANGE_ID_ERROR.MISSING;
-    },
+    }
 
     _computeLabelNames(labels) {
       return Object.keys(labels).sort();
-    },
+    }
 
     _computeLabelValues(labelName, labels) {
       const result = [];
@@ -1039,7 +1060,7 @@
         }
       }
       return result;
-    },
+    }
 
     _computeReplyButtonLabel(changeRecord, canStartReview) {
       // Polymer 2: check for undefined
@@ -1061,7 +1082,7 @@
         label += ' (' + draftCount + ')';
       }
       return label;
-    },
+    }
 
     _handleOpenReplyDialog(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1077,7 +1098,7 @@
         e.preventDefault();
         this._openReplyDialog(this.$.replyDialog.FocusTarget.ANY);
       });
-    },
+    }
 
     _handleOpenDownloadDialogShortcut(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1085,7 +1106,7 @@
 
       e.preventDefault();
       this.$.downloadOverlay.open();
-    },
+    }
 
     _handleEditTopic(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1093,13 +1114,13 @@
 
       e.preventDefault();
       this.$.metadata.editTopic();
-    },
+    }
 
     _handleRefreshChange(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
       e.preventDefault();
       Gerrit.Nav.navigateToChange(this._change);
-    },
+    }
 
     _handleToggleChangeStar(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1107,7 +1128,7 @@
 
       e.preventDefault();
       this.$.changeStar.toggleStar();
-    },
+    }
 
     _handleUpToDashboard(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1115,7 +1136,7 @@
 
       e.preventDefault();
       this._determinePageBack();
-    },
+    }
 
     _handleExpandAllMessages(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1123,7 +1144,7 @@
 
       e.preventDefault();
       this.messagesList.handleExpandCollapse(true);
-    },
+    }
 
     _handleCollapseAllMessages(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1131,7 +1152,7 @@
 
       e.preventDefault();
       this.messagesList.handleExpandCollapse(false);
-    },
+    }
 
     _handleOpenDiffPrefsShortcut(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -1141,14 +1162,14 @@
 
       e.preventDefault();
       this.$.fileList.openDiffPrefs();
-    },
+    }
 
     _determinePageBack() {
       // Default backPage to root if user came to change view page
       // via an email link, etc.
       Gerrit.Nav.navigateToRelativeUrl(this.backPage ||
           Gerrit.Nav.getUrlForRoot());
-    },
+    }
 
     _handleLabelRemoved(splices, path) {
       for (const splice of splices) {
@@ -1163,7 +1184,7 @@
           }
         }
       }
-    },
+    }
 
     _labelsChanged(changeRecord) {
       if (!changeRecord) { return; }
@@ -1174,7 +1195,7 @@
       this.$.jsAPI.handleEvent(this.$.jsAPI.EventType.LABEL_CHANGE, {
         change: this._change,
       });
-    },
+    }
 
     /**
      * @param {string=} opt_section
@@ -1186,7 +1207,7 @@
         Polymer.dom.flush();
         this.$.replyOverlay.center();
       });
-    },
+    }
 
     _handleReloadChange(e) {
       return this._reload().then(() => {
@@ -1197,19 +1218,19 @@
           Gerrit.Nav.navigateToChange(this._change);
         }
       });
-    },
+    }
 
     _handleGetChangeDetailError(response) {
       this.fire('page-error', {response});
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _getServerConfig() {
       return this.$.restAPI.getConfig();
-    },
+    }
 
     _getProjectConfig() {
       if (!this._change) return;
@@ -1217,18 +1238,18 @@
           config => {
             this._projectConfig = config;
           });
-    },
+    }
 
     _getPreferences() {
       return this.$.restAPI.getPreferences();
-    },
+    }
 
     _prepareCommitMsgForLinkify(msg) {
       // TODO(wyatta) switch linkify sequence, see issue 5526.
       // This is a zero-with space. It is added to prevent the linkify library
       // from including R= or CC= as part of the email address.
       return msg.replace(REVIEWERS_REGEX, '$1=\u200B');
-    },
+    }
 
     /**
      * Utility function to make the necessary modifications to a change in the
@@ -1258,7 +1279,7 @@
         change.revisions[edit.commit.commit].actions =
             change.revisions[edit.base_revision].actions;
       }
-    },
+    }
 
     _getChangeDetail() {
       const detailCompletes = this.$.restAPI.getChangeDetail(
@@ -1288,7 +1309,6 @@
               this._latestCommitMessage = null;
             }
 
-
             const lineHeight = getComputedStyle(this).lineHeight;
 
             // Slice returns a number as a string, convert to an int.
@@ -1313,25 +1333,25 @@
                       parseInt(this._patchRange.patchNum, 10));
             }
           });
-    },
+    }
 
     _isSubmitEnabled(revisionActions) {
       return !!(revisionActions && revisionActions.submit &&
         revisionActions.submit.enabled);
-    },
+    }
 
     _getEdit() {
       return this.$.restAPI.getChangeEdit(this._changeNum, true);
-    },
+    }
 
     _getLatestCommitMessage() {
       return this.$.restAPI.getChangeCommitInfo(this._changeNum,
           this.computeLatestPatchNum(this._allPatchSets)).then(commitInfo => {
-            if (!commitInfo) return Promise.resolve();
-            this._latestCommitMessage =
+        if (!commitInfo) return Promise.resolve();
+        this._latestCommitMessage =
                     this._prepareCommitMsgForLinkify(commitInfo.message);
-          });
-    },
+      });
+    }
 
     _getLatestRevisionSHA(change) {
       if (change.current_revision) {
@@ -1350,7 +1370,7 @@
         }
       }
       return latestRev;
-    },
+    }
 
     _getCommitInfo() {
       return this.$.restAPI.getChangeCommitInfo(
@@ -1358,13 +1378,13 @@
           commitInfo => {
             this._commitInfo = commitInfo;
           });
-    },
+    }
 
     _reloadDraftsWithCallback(e) {
       return this._reloadDrafts().then(() => {
         return e.detail.resolve();
       });
-    },
+    }
 
     /**
      * Fetches a new changeComment object, and data for all types of comments
@@ -1376,9 +1396,9 @@
             this._changeComments = comments;
             this._diffDrafts = Object.assign({}, this._changeComments.drafts);
             this._commentThreads = this._changeComments.getAllThreadsForChange()
-              .map(c => Object.assign({}, c));
+                .map(c => Object.assign({}, c));
           });
-    },
+    }
 
     /**
      * Fetches a new changeComment object, but only updated data for drafts is
@@ -1390,7 +1410,7 @@
             this._changeComments = comments;
             this._diffDrafts = Object.assign({}, this._changeComments.drafts);
           });
-    },
+    }
 
     /**
      * Reload the change.
@@ -1497,7 +1517,7 @@
       });
 
       return coreDataPromise;
-    },
+    }
 
     /**
      * Kicks off requests for resources that rely on the patch range
@@ -1508,7 +1528,7 @@
         this._getCommitInfo(),
         this.$.fileList.reload(),
       ]);
-    },
+    }
 
     _getMergeability() {
       if (!this._change) {
@@ -1528,59 +1548,59 @@
       return this.$.restAPI.getMergeable(this._changeNum).then(m => {
         this._mergeable = m.mergeable;
       });
-    },
+    }
 
     _computeCanStartReview(change) {
       return !!(change.actions && change.actions.ready &&
           change.actions.ready.enabled);
-    },
+    }
 
-    _computeReplyDisabled() { return false; },
+    _computeReplyDisabled() { return false; }
 
     _computeChangePermalinkAriaLabel(changeNum) {
       return 'Change ' + changeNum;
-    },
+    }
 
     _computeCommitClass(collapsed, commitMessage) {
       if (this._computeCommitToggleHidden(commitMessage)) { return ''; }
       return collapsed ? 'collapsed' : '';
-    },
+    }
 
     _computeRelatedChangesClass(collapsed) {
       return collapsed ? 'collapsed' : '';
-    },
+    }
 
     _computeCollapseText(collapsed) {
       // Symbols are up and down triangles.
       return collapsed ? '\u25bc Show more' : '\u25b2 Show less';
-    },
+    }
 
     _toggleCommitCollapsed() {
       this._commitCollapsed = !this._commitCollapsed;
       if (this._commitCollapsed) {
         window.scrollTo(0, 0);
       }
-    },
+    }
 
     _toggleRelatedChangesCollapsed() {
       this._relatedChangesCollapsed = !this._relatedChangesCollapsed;
       if (this._relatedChangesCollapsed) {
         window.scrollTo(0, 0);
       }
-    },
+    }
 
     _computeCommitToggleHidden(commitMessage) {
       if (!commitMessage) { return true; }
       return commitMessage.split('\n').length < MIN_LINES_FOR_COMMIT_COLLAPSE;
-    },
+    }
 
     _getOffsetHeight(element) {
       return element.offsetHeight;
-    },
+    }
 
     _getScrollHeight(element) {
       return element.scrollHeight;
-    },
+    }
 
     /**
      * Get the line height of an element to the nearest integer.
@@ -1588,7 +1608,7 @@
     _getLineHeight(element) {
       const lineHeightStr = getComputedStyle(element).lineHeight;
       return Math.round(lineHeightStr.slice(0, lineHeightStr.length - 2));
-    },
+    }
 
     /**
      * New max height for the related changes section, shorter than the existing
@@ -1647,7 +1667,7 @@
       }
 
       this.updateStyles(stylesToUpdate);
-    },
+    }
 
     _computeShowRelatedToggle() {
       // Make sure the max height has been applied, since there is now content
@@ -1667,7 +1687,7 @@
         return this._showRelatedToggle = true;
       }
       this._showRelatedToggle = false;
-    },
+    }
 
     _updateToggleContainerClass(showRelatedToggle) {
       if (showRelatedToggle) {
@@ -1675,7 +1695,7 @@
       } else {
         this.$.relatedChangesToggle.classList.remove('showToggle');
       }
-    },
+    }
 
     _startUpdateCheckTimer() {
       if (!this._serverConfig ||
@@ -1718,14 +1738,14 @@
           });
         });
       }, this._serverConfig.change.update_delay * 1000);
-    },
+    }
 
     _cancelUpdateCheckTimer() {
       if (this._updateCheckTimerHandle) {
         this.cancelAsync(this._updateCheckTimerHandle);
       }
       this._updateCheckTimerHandle = null;
-    },
+    }
 
     _handleVisibilityChange() {
       if (document.hidden && this._updateCheckTimerHandle) {
@@ -1733,17 +1753,17 @@
       } else if (!this._updateCheckTimerHandle) {
         this._startUpdateCheckTimer();
       }
-    },
+    }
 
     _handleTopicChanged() {
       this.$.relatedChanges.reload();
-    },
+    }
 
     _computeHeaderClass(editMode) {
       const classes = ['header'];
       if (editMode) { classes.push('editMode'); }
       return classes.join(' ');
-    },
+    }
 
     _computeEditMode(patchRangeRecord, paramsRecord) {
       if ([patchRangeRecord, paramsRecord].some(arg => arg === undefined)) {
@@ -1754,7 +1774,7 @@
 
       const patchRange = patchRangeRecord.base || {};
       return this.patchNumEquals(patchRange.patchNum, this.EDIT_NAME);
-    },
+    }
 
     _handleFileActionTap(e) {
       e.preventDefault();
@@ -1776,11 +1796,11 @@
           controls.openRestoreDialog(path);
           break;
       }
-    },
+    }
 
     _computeCommitMessageKey(number, revision) {
       return `c${number}_rev${revision}`;
-    },
+    }
 
     _patchNumChanged(patchNumStr) {
       if (!this._selectedRevision) {
@@ -1792,7 +1812,7 @@
       }
       this._selectedRevision = Object.values(this._change.revisions).find(
           revision => revision._number === patchNum);
-    },
+    }
 
     /**
      * If an edit exists already, load it. Otherwise, toggle edit mode via the
@@ -1800,7 +1820,7 @@
      */
     _handleEditTap() {
       const editInfo = Object.values(this._change.revisions).find(info =>
-          info._number === this.EDIT_NAME);
+        info._number === this.EDIT_NAME);
 
       if (editInfo) {
         Gerrit.Nav.navigateToChange(this._change, this.EDIT_NAME);
@@ -1815,31 +1835,33 @@
         patchNum = this._patchRange.patchNum;
       }
       Gerrit.Nav.navigateToChange(this._change, patchNum, null, true);
-    },
+    }
 
     _handleStopEditTap() {
       Gerrit.Nav.navigateToChange(this._change, this._patchRange.patchNum);
-    },
+    }
 
     _resetReplyOverlayFocusStops() {
       this.$.replyOverlay.setFocusStops(this.$.replyDialog.getFocusStops());
-    },
+    }
 
     _handleToggleStar(e) {
       this.$.restAPI.saveChangeStarred(e.detail.change._number,
           e.detail.starred);
-    },
+    }
 
     _getRevisionInfo(change) {
       return new Gerrit.RevisionInfo(change);
-    },
+    }
 
     _computeCurrentRevision(currentRevision, revisions) {
       return currentRevision && revisions && revisions[currentRevision];
-    },
+    }
 
     _computeDiffPrefsDisabled(disableDiffPrefs, loggedIn) {
       return disableDiffPrefs || !loggedIn;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeView.is, GrChangeView);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.html b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.html
index f7d1a18..d9b8464 100644
--- a/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.html
+++ b/polygerrit-ui/app/elements/change/gr-change-view/gr-change-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -176,7 +176,7 @@
           assert.isFalse(element.$.replyOverlay.opened);
           assert(openSpy.lastCall.calledWithExactly(
               element.$.replyDialog.FocusTarget.ANY),
-              '_openReplyDialog should have been passed ANY');
+          '_openReplyDialog should have been passed ANY');
           assert.equal(openSpy.callCount, 1);
           done();
         });
@@ -1046,7 +1046,7 @@
           MockInteractions.tap(element.$.replyBtn);
           assert(openStub.lastCall.calledWithExactly(
               element.$.replyDialog.FocusTarget.ANY),
-              '_openReplyDialog should have been passed ANY');
+          '_openReplyDialog should have been passed ANY');
           assert.equal(openStub.callCount, 1);
         });
 
@@ -1058,7 +1058,7 @@
             {message: {message: 'text'}});
         assert(openStub.lastCall.calledWithExactly(
             element.$.replyDialog.FocusTarget.BODY),
-            '_openReplyDialog should have been passed BODY');
+        '_openReplyDialog should have been passed BODY');
         assert.equal(openStub.callCount, 1);
         done();
       });
@@ -1362,7 +1362,6 @@
             '96px');
       });
 
-
       suite('update checks', () => {
         setup(() => {
           sandbox.spy(element, '_startUpdateCheckTimer');
@@ -1483,7 +1482,7 @@
 
     test('_computeEditMode', () => {
       const callCompute = (range, params) =>
-          element._computeEditMode({base: range}, {base: params});
+        element._computeEditMode({base: range}, {base: params});
       assert.isFalse(callCompute({}, {}));
       assert.isTrue(callCompute({}, {edit: true}));
       assert.isFalse(callCompute({basePatchNum: 'PARENT', patchNum: 1}, {}));
@@ -1703,7 +1702,7 @@
 
       element._patchRange = {patchNum: 1};
       element.$.actions.dispatchEvent(new CustomEvent('stop-edit-tap',
-            {bubbles: false}));
+          {bubbles: false}));
     });
 
     suite('plugin endpoints', () => {
diff --git a/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list.js b/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list.js
index cbc7e42..60d459e 100644
--- a/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list.js
+++ b/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list.js
@@ -16,46 +16,54 @@
  */
 (function() {
   'use strict';
-  Polymer({
-    is: 'gr-comment-list',
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.PathListBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.PathListMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrCommentList extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.PathListBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-comment-list'; }
 
-    properties: {
-      changeNum: Number,
-      comments: Object,
-      patchNum: Number,
-      projectName: String,
-      /** @type {?} */
-      projectConfig: Object,
-    },
+    static get properties() {
+      return {
+        changeNum: Number,
+        comments: Object,
+        patchNum: Number,
+        projectName: String,
+        /** @type {?} */
+        projectConfig: Object,
+      };
+    }
 
     _computeFilesFromComments(comments) {
       const arr = Object.keys(comments || {});
       return arr.sort(this.specialFilePathCompare);
-    },
+    }
 
     _isOnParent(comment) {
       return comment.side === 'PARENT';
-    },
+    }
 
     _computeDiffLineURL(file, changeNum, patchNum, comment) {
       const basePatchNum = comment.hasOwnProperty('parent') ?
-          -comment.parent : null;
+        -comment.parent : null;
       return Gerrit.Nav.getUrlForDiffById(this.changeNum, this.projectName,
           file, patchNum, basePatchNum, comment.line,
           this._isOnParent(comment));
-    },
+    }
 
     _computeCommentsForFile(comments, file) {
       // Changes are not picked up by the dom-repeat due to the array instance
       // identity not changing even when it has elements added/removed from it.
       return (comments[file] || []).slice();
-    },
+    }
 
     _computePatchDisplayName(comment) {
       if (this._isOnParent(comment)) {
@@ -65,6 +73,8 @@
         return `PS${comment.patch_set}, `;
       }
       return '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCommentList.is, GrCommentList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list_test.html b/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list_test.html
index c18ae8d..97be9b7 100644
--- a/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-comment-list/gr-comment-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-comment-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info.js b/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info.js
index e2fcdff..2a3fe89 100644
--- a/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info.js
+++ b/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info.js
@@ -17,23 +17,27 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-commit-info',
+  class GrCommitInfo extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-commit-info'; }
 
-    properties: {
-      change: Object,
-      /** @type {?} */
-      commitInfo: Object,
-      serverConfig: Object,
-      _showWebLink: {
-        type: Boolean,
-        computed: '_computeShowWebLink(change, commitInfo, serverConfig)',
-      },
-      _webLink: {
-        type: String,
-        computed: '_computeWebLink(change, commitInfo, serverConfig)',
-      },
-    },
+    static get properties() {
+      return {
+        change: Object,
+        /** @type {?} */
+        commitInfo: Object,
+        serverConfig: Object,
+        _showWebLink: {
+          type: Boolean,
+          computed: '_computeShowWebLink(change, commitInfo, serverConfig)',
+        },
+        _webLink: {
+          type: String,
+          computed: '_computeWebLink(change, commitInfo, serverConfig)',
+        },
+      };
+    }
 
     _getWeblink(change, commitInfo, config) {
       return Gerrit.Nav.getPatchSetWeblink(
@@ -43,7 +47,7 @@
             weblinks: commitInfo.web_links,
             config,
           });
-    },
+    }
 
     _computeShowWebLink(change, commitInfo, serverConfig) {
       // Polymer 2: check for undefined
@@ -53,7 +57,7 @@
 
       const weblink = this._getWeblink(change, commitInfo, serverConfig);
       return !!weblink && !!weblink.url;
-    },
+    }
 
     _computeWebLink(change, commitInfo, serverConfig) {
       // Polymer 2: check for undefined
@@ -63,12 +67,14 @@
 
       const {url} = this._getWeblink(change, commitInfo, serverConfig) || {};
       return url;
-    },
+    }
 
     _computeShortHash(commitInfo) {
       const {name} =
             this._getWeblink(this.change, commitInfo, this.serverConfig) || {};
       return name;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCommitInfo.is, GrCommitInfo);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info_test.html b/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info_test.html
index f271a70..2c5b431 100644
--- a/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info_test.html
+++ b/polygerrit-ui/app/elements/change/gr-commit-info/gr-commit-info_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-commit-info</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -101,7 +101,6 @@
           element.serverConfig), 'https://link-url');
     });
 
-
     test('ignore web links that are neither gitweb nor gitiles', () => {
       const router = document.createElement('gr-router');
       sandbox.stub(Gerrit.Nav, '_generateWeblinks',
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog.js
index 524876e..6ef5b69 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog.js
@@ -17,9 +17,17 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-confirm-abandon-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrConfirmAbandonDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-abandon-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -32,41 +40,42 @@
      * @event cancel
      */
 
-    properties: {
-      message: String,
-    },
+    static get properties() {
+      return {
+        message: String,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    keyBindings: {
-      'ctrl+enter meta+enter': '_handleEnterKey',
-    },
+    get keyBindings() {
+      return {
+        'ctrl+enter meta+enter': '_handleEnterKey',
+      };
+    }
 
     resetFocus() {
       this.$.messageInput.textarea.focus();
-    },
+    }
 
     _handleEnterKey(e) {
       this._confirm();
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this._confirm();
-    },
+    }
 
     _confirm() {
       this.fire('confirm', {reason: this.message}, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmAbandonDialog.is, GrConfirmAbandonDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog_test.html
index cc4b80e..e9964c5 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-abandon-dialog/gr-confirm-abandon-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-abandon-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog.js
index a0da331..669c6b1 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog.js
@@ -17,12 +17,15 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-confirm-cherrypick-conflict-dialog',
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmCherrypickConflictDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-cherrypick-conflict-dialog'; }
 
     /**
      * Fired when the confirm button is pressed.
@@ -40,12 +43,15 @@
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmCherrypickConflictDialog.is,
+      GrConfirmCherrypickConflictDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog_test.html
index f411de4..557972a 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-conflict-dialog/gr-confirm-cherrypick-conflict-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-cherrypick-conflict-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog.js
index bf84003..bdc5c10 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog.js
@@ -19,9 +19,15 @@
 
   const SUGGESTIONS_LIMIT = 15;
 
-  Polymer({
-    is: 'gr-confirm-cherrypick-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmCherrypickDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-cherrypick-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -34,29 +40,29 @@
      * @event cancel
      */
 
-    properties: {
-      branch: String,
-      baseCommit: String,
-      changeStatus: String,
-      commitMessage: String,
-      commitNum: String,
-      message: String,
-      project: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getProjectBranchesSuggestions.bind(this);
+    static get properties() {
+      return {
+        branch: String,
+        baseCommit: String,
+        changeStatus: String,
+        commitMessage: String,
+        commitNum: String,
+        message: String,
+        project: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getProjectBranchesSuggestions.bind(this);
+          },
         },
-      },
-    },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_computeMessage(changeStatus, commitNum, commitMessage)',
-    ],
+    static get observers() {
+      return [
+        '_computeMessage(changeStatus, commitNum, commitMessage)',
+      ];
+    }
 
     _computeMessage(changeStatus, commitNum, commitMessage) {
       // Polymer 2: check for undefined
@@ -74,23 +80,23 @@
         newMessage += '(cherry picked from commit ' + commitNum + ')';
       }
       this.message = newMessage;
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
+    }
 
     resetFocus() {
       this.$.branchInput.focus();
-    },
+    }
 
     _getProjectBranchesSuggestions(input) {
       if (input.startsWith('refs/heads/')) {
@@ -98,21 +104,24 @@
       }
       return this.$.restAPI.getRepoBranches(
           input, this.project, SUGGESTIONS_LIMIT).then(response => {
-            const branches = [];
-            let branch;
-            for (const key in response) {
-              if (!response.hasOwnProperty(key)) { continue; }
-              if (response[key].ref.startsWith('refs/heads/')) {
-                branch = response[key].ref.substring('refs/heads/'.length);
-              } else {
-                branch = response[key].ref;
-              }
-              branches.push({
-                name: branch,
-              });
-            }
-            return branches;
+        const branches = [];
+        let branch;
+        for (const key in response) {
+          if (!response.hasOwnProperty(key)) { continue; }
+          if (response[key].ref.startsWith('refs/heads/')) {
+            branch = response[key].ref.substring('refs/heads/'.length);
+          } else {
+            branch = response[key].ref;
+          }
+          branches.push({
+            name: branch,
           });
-    },
-  });
+        }
+        return branches;
+      });
+    }
+  }
+
+  customElements.define(GrConfirmCherrypickDialog.is,
+      GrConfirmCherrypickDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog_test.html
index 22a2aba..42310fb 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-cherrypick-dialog/gr-confirm-cherrypick-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-cherrypick-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog.js
index 23123c3..fb78bfb 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog.js
@@ -19,9 +19,15 @@
 
   const SUGGESTIONS_LIMIT = 15;
 
-  Polymer({
-    is: 'gr-confirm-move-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmMoveDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-move-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -34,33 +40,31 @@
      * @event cancel
      */
 
-    properties: {
-      branch: String,
-      message: String,
-      project: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getProjectBranchesSuggestions.bind(this);
+    static get properties() {
+      return {
+        branch: String,
+        message: String,
+        project: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getProjectBranchesSuggestions.bind(this);
+          },
         },
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+      };
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
+    }
 
     _getProjectBranchesSuggestions(input) {
       if (input.startsWith('refs/heads/')) {
@@ -68,21 +72,23 @@
       }
       return this.$.restAPI.getRepoBranches(
           input, this.project, SUGGESTIONS_LIMIT).then(response => {
-            const branches = [];
-            let branch;
-            for (const key in response) {
-              if (!response.hasOwnProperty(key)) { continue; }
-              if (response[key].ref.startsWith('refs/heads/')) {
-                branch = response[key].ref.substring('refs/heads/'.length);
-              } else {
-                branch = response[key].ref;
-              }
-              branches.push({
-                name: branch,
-              });
-            }
-            return branches;
+        const branches = [];
+        let branch;
+        for (const key in response) {
+          if (!response.hasOwnProperty(key)) { continue; }
+          if (response[key].ref.startsWith('refs/heads/')) {
+            branch = response[key].ref.substring('refs/heads/'.length);
+          } else {
+            branch = response[key].ref;
+          }
+          branches.push({
+            name: branch,
           });
-    },
-  });
+        }
+        return branches;
+      });
+    }
+  }
+
+  customElements.define(GrConfirmMoveDialog.is, GrConfirmMoveDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog_test.html
index 8d6e029..036950b 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-move-dialog/gr-confirm-move-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-move-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.js
index 1b884e7..7169437 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog.js
@@ -17,9 +17,10 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-confirm-rebase-dialog',
-
+  class GrConfirmRebaseDialog extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-confirm-rebase-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -32,24 +33,28 @@
      * @event cancel
      */
 
-    properties: {
-      branch: String,
-      changeNumber: Number,
-      hasParent: Boolean,
-      rebaseOnCurrent: Boolean,
-      _text: String,
-      _query: {
-        type: Function,
-        value() {
-          return this._getChangeSuggestions.bind(this);
+    static get properties() {
+      return {
+        branch: String,
+        changeNumber: Number,
+        hasParent: Boolean,
+        rebaseOnCurrent: Boolean,
+        _text: String,
+        _query: {
+          type: Function,
+          value() {
+            return this._getChangeSuggestions.bind(this);
+          },
         },
-      },
-      _recentChanges: Array,
-    },
+        _recentChanges: Array,
+      };
+    }
 
-    observers: [
-      '_updateSelectedOption(rebaseOnCurrent, hasParent)',
-    ],
+    static get observers() {
+      return [
+        '_updateSelectedOption(rebaseOnCurrent, hasParent)',
+      ];
+    }
 
     // This is called by gr-change-actions every time the rebase dialog is
     // re-opened. Unlike other autocompletes that make a request with each
@@ -71,36 +76,36 @@
             this._recentChanges = changes;
             return this._recentChanges;
           });
-    },
+    }
 
     _getRecentChanges() {
       if (this._recentChanges) {
         return Promise.resolve(this._recentChanges);
       }
       return this.fetchRecentChanges();
-    },
+    }
 
     _getChangeSuggestions(input) {
       return this._getRecentChanges().then(changes =>
-          this._filterChanges(input, changes));
-    },
+        this._filterChanges(input, changes));
+    }
 
     _filterChanges(input, changes) {
       return changes.filter(change => change.name.includes(input) &&
           change.value !== this.changeNumber);
-    },
+    }
 
     _displayParentOption(rebaseOnCurrent, hasParent) {
       return hasParent && rebaseOnCurrent;
-    },
+    }
 
     _displayParentUpToDateMsg(rebaseOnCurrent, hasParent) {
       return hasParent && !rebaseOnCurrent;
-    },
+    }
 
     _displayTipOption(rebaseOnCurrent, hasParent) {
       return !(!rebaseOnCurrent && !hasParent);
-    },
+    }
 
     /**
      * There is a subtle but important difference between setting the base to an
@@ -115,7 +120,7 @@
       // Change numbers will have their description appended by the
       // autocomplete.
       return this._text.split(':')[0];
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
@@ -123,22 +128,22 @@
       this.dispatchEvent(new CustomEvent('confirm',
           {detail: {base: this._getSelectedBase()}}));
       this._text = '';
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.dispatchEvent(new CustomEvent('cancel'));
       this._text = '';
-    },
+    }
 
     _handleRebaseOnOther() {
       this.$.parentInput.focus();
-    },
+    }
 
     _handleEnterChangeNumberClick() {
       this.$.rebaseOnOtherInput.checked = true;
-    },
+    }
 
     /**
      * Sets the default radio button based on the state of the app and
@@ -157,6 +162,8 @@
       } else {
         this.$.rebaseOnOtherInput.checked = true;
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmRebaseDialog.is, GrConfirmRebaseDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.html
index cd5b130..b116171 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-rebase-dialog/gr-confirm-rebase-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-rebase-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.js
index 662b64c..e95f2c9 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog.js
@@ -20,9 +20,15 @@
   const ERR_COMMIT_NOT_FOUND =
       'Unable to find the commit hash of this change.';
 
-  Polymer({
-    is: 'gr-confirm-revert-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmRevertDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-revert-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -35,13 +41,11 @@
      * @event cancel
      */
 
-    properties: {
-      message: String,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        message: String,
+      };
+    }
 
     populateRevertMessage(message, commitHash) {
       // Figure out what the revert title should be.
@@ -55,18 +59,20 @@
 
       this.message = `${revertTitle}\n\n${revertCommitText}\n\n` +
           `Reason for revert: <INSERT REASONING HERE>\n`;
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmRevertDialog.is, GrConfirmRevertDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_test.html
index 6e41555..dbdfba2 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-dialog/gr-confirm-revert-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-revert-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.html b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.html
new file mode 100644
index 0000000..b334989
--- /dev/null
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.html
@@ -0,0 +1,71 @@
+<!--
+@license
+Copyright (C) 2019 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<link rel="import" href="/bower_components/iron-autogrow-textarea/iron-autogrow-textarea.html">
+<link rel="import" href="/bower_components/polymer/polymer.html">
+<link rel="import" href="../../../behaviors/fire-behavior/fire-behavior.html">
+<link rel="import" href="../../shared/gr-dialog/gr-dialog.html">
+<link rel="import" href="../../../styles/shared-styles.html">
+
+<dom-module id="gr-confirm-revert-submission-dialog">
+  <template>
+    <!-- TODO(taoalpha): move all shared styles to a style module. -->
+    <style include="shared-styles">
+      :host {
+        display: block;
+      }
+      :host([disabled]) {
+        opacity: .5;
+        pointer-events: none;
+      }
+      label {
+        cursor: pointer;
+        display: block;
+        width: 100%;
+      }
+      iron-autogrow-textarea {
+        font-family: var(--monospace-font-family);
+        padding: 0;
+        width: 73ch; /* Add a char to account for the border. */
+
+        --iron-autogrow-textarea {
+          border: 1px solid var(--border-color);
+          box-sizing: border-box;
+          font-family: var(--monospace-font-family);
+        }
+      }
+    </style>
+    <gr-dialog
+        confirm-label="Revert Submission"
+        on-confirm="_handleConfirmTap"
+        on-cancel="_handleCancelTap">
+      <div class="header" slot="header">Revert Submission</div>
+      <div class="main" slot="main">
+        <label for="messageInput">
+          Revert Commit Message
+        </label>
+        <iron-autogrow-textarea
+            id="messageInput"
+            class="message"
+            autocomplete="on"
+            max-rows="15"
+            bind-value="{{message}}"></iron-autogrow-textarea>
+      </div>
+    </gr-dialog>
+  </template>
+  <script src="gr-confirm-revert-submission-dialog.js"></script>
+</dom-module>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.js
new file mode 100644
index 0000000..04b16ee
--- /dev/null
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog.js
@@ -0,0 +1,76 @@
+/**
+ * @license
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+(function() {
+  'use strict';
+
+  const ERR_COMMIT_NOT_FOUND =
+      'Unable to find the commit hash of this change.';
+
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmRevertSubmissionDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-revert-submission-dialog'; }
+    /**
+     * Fired when the confirm button is pressed.
+     *
+     * @event confirm
+     */
+
+    /**
+     * Fired when the cancel button is pressed.
+     *
+     * @event cancel
+     */
+
+    static get properties() {
+      return {
+        message: String,
+      };
+    }
+
+    populateRevertSubmissionMessage(message, commitHash) {
+      // Follow the same convention of the revert
+      const revertTitle = 'Revert submission';
+      if (!commitHash) {
+        this.fire('show-alert', {message: ERR_COMMIT_NOT_FOUND});
+        return;
+      }
+      this.message = `${revertTitle}\n\n` +
+          `Reason for revert: <INSERT REASONING HERE>\n`;
+    }
+
+    _handleConfirmTap(e) {
+      e.preventDefault();
+      e.stopPropagation();
+      this.fire('confirm', null, {bubbles: false});
+    }
+
+    _handleCancelTap(e) {
+      e.preventDefault();
+      e.stopPropagation();
+      this.fire('cancel', null, {bubbles: false});
+    }
+  }
+
+  customElements.define(GrConfirmRevertSubmissionDialog.is,
+      GrConfirmRevertSubmissionDialog);
+})();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog_test.html
new file mode 100644
index 0000000..cc4bd54
--- /dev/null
+++ b/polygerrit-ui/app/elements/change/gr-confirm-revert-submission-dialog/gr-confirm-revert-submission-dialog_test.html
@@ -0,0 +1,100 @@
+<!DOCTYPE html>
+<!--
+@license
+Copyright (C) 2019 The Android Open Source Project
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
+<title>gr-confirm-revert-submission-dialog</title>
+
+<script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
+
+<script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
+<script src="/bower_components/web-component-tester/browser.js"></script>
+<link rel="import" href="../../../test/common-test-setup.html"/>
+<link rel="import" href="gr-confirm-revert-submission-dialog.html">
+
+<script>void(0);</script>
+
+<test-fixture id="basic">
+  <template>
+    <gr-confirm-revert-submission-dialog>
+    </gr-confirm-revert-submission-dialog>
+  </template>
+</test-fixture>
+
+<script>
+  suite('gr-confirm-revert-submission-dialog tests', () => {
+    let element;
+    let sandbox;
+
+    setup(() => {
+      element = fixture('basic');
+      sandbox =sinon.sandbox.create();
+    });
+
+    teardown(() => sandbox.restore());
+
+    test('no match', () => {
+      assert.isNotOk(element.message);
+      const alertStub = sandbox.stub();
+      element.addEventListener('show-alert', alertStub);
+      element.populateRevertSubmissionMessage(
+          'not a commitHash in sight'
+      );
+      assert.isTrue(alertStub.calledOnce);
+    });
+
+    test('single line', () => {
+      assert.isNotOk(element.message);
+      element.populateRevertSubmissionMessage(
+          'one line commit\n\nChange-Id: abcdefg\n',
+          'abcd123');
+      const expected = 'Revert submission\n\n' +
+        'Reason for revert: <INSERT REASONING HERE>\n';
+      assert.equal(element.message, expected);
+    });
+
+    test('multi line', () => {
+      assert.isNotOk(element.message);
+      element.populateRevertSubmissionMessage(
+          'many lines\ncommit\n\nmessage\n\nChange-Id: abcdefg\n',
+          'abcd123');
+      const expected = 'Revert submission\n\n' +
+        'Reason for revert: <INSERT REASONING HERE>\n';
+      assert.equal(element.message, expected);
+    });
+
+    test('issue above change id', () => {
+      assert.isNotOk(element.message);
+      element.populateRevertSubmissionMessage(
+          'test \nvery\n\ncommit\n\nBug: Issue 42\nChange-Id: abcdefg\n',
+          'abcd123');
+      const expected = 'Revert submission\n\n' +
+          'Reason for revert: <INSERT REASONING HERE>\n';
+      assert.equal(element.message, expected);
+    });
+
+    test('revert a revert', () => {
+      assert.isNotOk(element.message);
+      element.populateRevertSubmissionMessage(
+          'Revert "one line commit"\n\nChange-Id: abcdefg\n',
+          'abcd123');
+      const expected = 'Revert submission\n\n' +
+        'Reason for revert: <INSERT REASONING HERE>\n';
+      assert.equal(element.message, expected);
+    });
+  });
+</script>
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog.js b/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog.js
index e86e21c..05841e9 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog.js
@@ -17,9 +17,10 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-confirm-submit-dialog',
-
+  class GrConfirmSubmitDialog extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-confirm-submit-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -32,37 +33,41 @@
      * @event cancel
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * @type {{
        *    is_private: boolean,
        *    subject: string,
        *  }}
        */
-      change: Object,
+        change: Object,
 
-      /**
+        /**
        * @type {{
        *    label: string,
        *  }}
        */
-      action: Object,
-    },
+        action: Object,
+      };
+    }
 
     resetFocus(e) {
       this.$.dialog.resetFocus();
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.dispatchEvent(new CustomEvent('confirm', {bubbles: false}));
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.dispatchEvent(new CustomEvent('cancel', {bubbles: false}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmSubmitDialog.is, GrConfirmSubmitDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog_test.html b/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog_test.html
index 40fa29a..515147f 100644
--- a/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-confirm-submit-dialog/gr-confirm-submit-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-confirm-submit-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.html b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.html
index e20bbd7..4ddc876 100644
--- a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.html
+++ b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.html
@@ -27,16 +27,13 @@
   <template>
     <style include="shared-styles">
       :host {
-        background-color: var(--dialog-background-color);
         display: block;
+        padding: var(--spacing-m) 0;
       }
       section {
         display: flex;
         padding: var(--spacing-m) var(--spacing-xl);
       }
-      section:not(:first-of-type) {
-        border-top: 1px solid var(--border-color);
-      }
       .flexContainer {
         display: flex;
         justify-content: space-between;
@@ -76,9 +73,9 @@
       }
     </style>
     <section>
-      <span class="title">
+      <h3 class="title">
         Patch set [[patchNum]] of [[_computePatchSetQuantity(change.revisions)]]
-      </span>
+      </h3>
     </section>
     <section class$="[[_computeShowDownloadCommands(_schemes)]]">
       <gr-download-commands
diff --git a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.js b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.js
index 90cc60f..ab849de 100644
--- a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog.js
@@ -17,40 +17,47 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-download-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrDownloadDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-download-dialog'; }
     /**
      * Fired when the user presses the close button.
      *
      * @event close
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {{ revisions: Array }} */
-      change: Object,
-      patchNum: String,
-      /** @type {?} */
-      config: Object,
+        change: Object,
+        patchNum: String,
+        /** @type {?} */
+        config: Object,
 
-      _schemes: {
-        type: Array,
-        value() { return []; },
-        computed: '_computeSchemes(change, patchNum)',
-        observer: '_schemesChanged',
-      },
-      _selectedScheme: String,
-    },
+        _schemes: {
+          type: Array,
+          value() { return []; },
+          computed: '_computeSchemes(change, patchNum)',
+          observer: '_schemesChanged',
+        },
+        _selectedScheme: String,
+      };
+    }
 
-    hostAttributes: {
-      role: 'dialog',
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'dialog');
+    }
 
     focus() {
       if (this._schemes.length) {
@@ -58,7 +65,7 @@
       } else {
         this.$.download.focus();
       }
-    },
+    }
 
     getFocusStops() {
       const links = this.$$('#archives').querySelectorAll('a');
@@ -66,7 +73,7 @@
         start: this.$.closeButton,
         end: links[links.length - 1],
       };
-    },
+    }
 
     _computeDownloadCommands(change, patchNum, _selectedScheme) {
       let commandObj;
@@ -87,7 +94,7 @@
         });
       }
       return commands;
-    },
+    }
 
     /**
      * @param {!Object} change
@@ -97,7 +104,7 @@
      */
     _computeZipDownloadLink(change, patchNum) {
       return this._computeDownloadLink(change, patchNum, true);
-    },
+    }
 
     /**
      * @param {!Object} change
@@ -107,7 +114,7 @@
      */
     _computeZipDownloadFilename(change, patchNum) {
       return this._computeDownloadFilename(change, patchNum, true);
-    },
+    }
 
     /**
      * @param {!Object} change
@@ -123,8 +130,7 @@
       }
       return this.changeBaseURL(change.project, change._number, patchNum) +
           '/patch?' + (opt_zip ? 'zip' : 'download');
-    },
-
+    }
 
     /**
      * @param {!Object} change
@@ -147,7 +153,7 @@
         }
       }
       return shortRev + '.diff.' + (opt_zip ? 'zip' : 'base64');
-    },
+    }
 
     _computeHidePatchFile(change, patchNum) {
       // Polymer 2: check for undefined
@@ -157,12 +163,12 @@
       for (const rev of Object.values(change.revisions || {})) {
         if (this.patchNumEquals(rev._number, patchNum)) {
           const parentLength = rev.commit && rev.commit.parents ?
-                rev.commit.parents.length : 0;
+            rev.commit.parents.length : 0;
           return parentLength == 0;
         }
       }
       return false;
-    },
+    }
 
     _computeArchiveDownloadLink(change, patchNum, format) {
       // Polymer 2: check for undefined
@@ -171,7 +177,7 @@
       }
       return this.changeBaseURL(change.project, change._number, patchNum) +
           '/archive?format=' + format;
-    },
+    }
 
     _computeSchemes(change, patchNum) {
       // Polymer 2: check for undefined
@@ -189,28 +195,30 @@
         }
       }
       return [];
-    },
+    }
 
     _computePatchSetQuantity(revisions) {
       if (!revisions) { return 0; }
       return Object.keys(revisions).length;
-    },
+    }
 
     _handleCloseTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('close', null, {bubbles: false});
-    },
+    }
 
     _schemesChanged(schemes) {
       if (schemes.length === 0) { return; }
       if (!schemes.includes(this._selectedScheme)) {
         this._selectedScheme = schemes.sort()[0];
       }
-    },
+    }
 
     _computeShowDownloadCommands(schemes) {
       return schemes.length ? '' : 'hidden';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDownloadDialog.is, GrDownloadDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog_test.html b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog_test.html
index de02923..0f1260f 100644
--- a/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-download-dialog/gr-download-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-download-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -182,7 +182,7 @@
       test('computed fields', () => {
         assert.equal(element._computeArchiveDownloadLink(
             {project: 'test/project', _number: 123}, 2, 'tgz'),
-            '/changes/test%2Fproject~123/revisions/2/archive?format=tgz');
+        '/changes/test%2Fproject~123/revisions/2/archive?format=tgz');
       });
 
       test('close event', done => {
diff --git a/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header.js b/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header.js
index 2126433..dded147 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header.js
+++ b/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header.js
@@ -21,9 +21,17 @@
   const PATCH_DESC_MAX_LENGTH = 500;
   const MERGED_STATUS = 'MERGED';
 
-  Polymer({
-    is: 'gr-file-list-header',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  class GrFileListHeader extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-file-list-header'; }
     /**
      * @event expand-diffs
      */
@@ -48,72 +56,71 @@
      * @event open-upload-help-dialog
      */
 
-    properties: {
-      account: Object,
-      allPatchSets: Array,
-      /** @type {?} */
-      change: Object,
-      changeNum: String,
-      changeUrl: String,
-      changeComments: Object,
-      commitInfo: Object,
-      editMode: Boolean,
-      loggedIn: Boolean,
-      serverConfig: Object,
-      shownFileCount: Number,
-      diffPrefs: Object,
-      diffPrefsDisabled: Boolean,
-      diffViewMode: {
-        type: String,
-        notify: true,
-      },
-      patchNum: String,
-      basePatchNum: String,
-      filesExpanded: String,
-      // Caps the number of files that can be shown and have the 'show diffs' /
-      // 'hide diffs' buttons still be functional.
-      _maxFilesForBulkActions: {
-        type: Number,
-        readOnly: true,
-        value: 225,
-      },
-      _patchsetDescription: {
-        type: String,
-        value: '',
-      },
-      showTitle: {
-        type: Boolean,
-        value: true,
-      },
-      _descriptionReadOnly: {
-        type: Boolean,
-        computed: '_computeDescriptionReadOnly(loggedIn, change, account)',
-      },
-      revisionInfo: Object,
-    },
+    static get properties() {
+      return {
+        account: Object,
+        allPatchSets: Array,
+        /** @type {?} */
+        change: Object,
+        changeNum: String,
+        changeUrl: String,
+        changeComments: Object,
+        commitInfo: Object,
+        editMode: Boolean,
+        loggedIn: Boolean,
+        serverConfig: Object,
+        shownFileCount: Number,
+        diffPrefs: Object,
+        diffPrefsDisabled: Boolean,
+        diffViewMode: {
+          type: String,
+          notify: true,
+        },
+        patchNum: String,
+        basePatchNum: String,
+        filesExpanded: String,
+        // Caps the number of files that can be shown and have the 'show diffs' /
+        // 'hide diffs' buttons still be functional.
+        _maxFilesForBulkActions: {
+          type: Number,
+          readOnly: true,
+          value: 225,
+        },
+        _patchsetDescription: {
+          type: String,
+          value: '',
+        },
+        showTitle: {
+          type: Boolean,
+          value: true,
+        },
+        _descriptionReadOnly: {
+          type: Boolean,
+          computed: '_computeDescriptionReadOnly(loggedIn, change, account)',
+        },
+        revisionInfo: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-    ],
-
-    observers: [
-      '_computePatchSetDescription(change, patchNum)',
-    ],
+    static get observers() {
+      return [
+        '_computePatchSetDescription(change, patchNum)',
+      ];
+    }
 
     setDiffViewMode(mode) {
       this.$.modeSelect.setMode(mode);
-    },
+    }
 
     _expandAllDiffs() {
       this._expanded = true;
       this.fire('expand-diffs');
-    },
+    }
 
     _collapseAllDiffs() {
       this._expanded = false;
       this.fire('collapse-diffs');
-    },
+    }
 
     _computeExpandedClass(filesExpanded) {
       const classes = [];
@@ -125,11 +132,11 @@
         classes.push('openFile');
       }
       return classes.join(' ');
-    },
+    }
 
     _computeDescriptionPlaceholder(readOnly) {
       return (readOnly ? 'No' : 'Add') + ' patchset description';
-    },
+    }
 
     _computeDescriptionReadOnly(loggedIn, change, account) {
       // Polymer 2: check for undefined
@@ -138,7 +145,7 @@
       }
 
       return !(loggedIn && (account._account_id === change.owner._account_id));
-    },
+    }
 
     _computePatchSetDescription(change, patchNum) {
       // Polymer 2: check for undefined
@@ -148,12 +155,12 @@
 
       const rev = this.getRevisionByPatchNum(change.revisions, patchNum);
       this._patchsetDescription = (rev && rev.description) ?
-          rev.description.substring(0, PATCH_DESC_MAX_LENGTH) : '';
-    },
+        rev.description.substring(0, PATCH_DESC_MAX_LENGTH) : '';
+    }
 
     _handleDescriptionRemoved(e) {
       return this._updateDescription('', e);
-    },
+    }
 
     /**
      * @param {!Object} revisions The revisions object keyed by revision hashes
@@ -167,12 +174,12 @@
           return rev;
         }
       }
-    },
+    }
 
     _handleDescriptionChanged(e) {
       const desc = e.detail.trim();
       this._updateDescription(desc, e);
-    },
+    }
 
     /**
      * Update the patchset description with the rest API.
@@ -197,43 +204,43 @@
             if (target) { target.disabled = false; }
             return;
           });
-    },
+    }
 
     _computePrefsButtonHidden(prefs, diffPrefsDisabled) {
       return diffPrefsDisabled || !prefs;
-    },
+    }
 
     _fileListActionsVisible(shownFileCount, maxFilesForBulkActions) {
       return shownFileCount <= maxFilesForBulkActions;
-    },
+    }
 
     _handlePatchChange(e) {
       const {basePatchNum, patchNum} = e.detail;
       if (this.patchNumEquals(basePatchNum, this.basePatchNum) &&
           this.patchNumEquals(patchNum, this.patchNum)) { return; }
       Gerrit.Nav.navigateToChange(this.change, patchNum, basePatchNum);
-    },
+    }
 
     _handlePrefsTap(e) {
       e.preventDefault();
       this.fire('open-diff-prefs');
-    },
+    }
 
     _handleIncludedInTap(e) {
       e.preventDefault();
       this.fire('open-included-in-dialog');
-    },
+    }
 
     _handleDownloadTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.dispatchEvent(
           new CustomEvent('open-download-dialog', {bubbles: false}));
-    },
+    }
 
     _computeEditModeClass(editMode) {
       return editMode ? 'editMode' : '';
-    },
+    }
 
     _computePatchInfoClass(patchNum, allPatchSets) {
       const latestNum = this.computeLatestPatchNum(allPatchSets);
@@ -241,27 +248,29 @@
         return '';
       }
       return 'patchInfoOldPatchSet';
-    },
+    }
 
     _hideIncludedIn(change) {
       return change && change.status === MERGED_STATUS ? '' : 'hide';
-    },
+    }
 
     _handleUploadTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.dispatchEvent(
           new CustomEvent('open-upload-help-dialog', {bubbles: false}));
-    },
+    }
 
     _computeUploadHelpContainerClass(change, account) {
       const changeIsMerged = change && change.status === MERGED_STATUS;
       const ownerId = change && change.owner && change.owner._account_id ?
-          change.owner._account_id : null;
+        change.owner._account_id : null;
       const userId = account && account._account_id;
       const userIsOwner = ownerId && userId && ownerId === userId;
       const hideContainer = !userIsOwner || changeIsMerged;
       return 'uploadContainer desktop' + (hideContainer ? ' hide' : '');
-    },
-  });
+    }
+  }
+
+  customElements.define(GrFileListHeader.is, GrFileListHeader);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header_test.html b/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header_test.html
index ac626ab..ea7ea8f 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header_test.html
+++ b/polygerrit-ui/app/elements/change/gr-file-list-header/gr-file-list-header_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-file-list-header</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.html b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.html
index 0668e14..318633d 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.html
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.html
@@ -433,7 +433,6 @@
                 no-auto-render
                 show-load-failure
                 display-line="[[_displayLine]]"
-                inline-index=[[index]]
                 hidden="[[!_isFileExpanded(file.__path, _expandedFilePaths.*)]]"
                 change-num="[[changeNum]]"
                 patch-range="[[patchRange]]"
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
index 4903467..fb57164 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list.js
@@ -41,162 +41,175 @@
     U: 'Unchanged',
   };
 
-  Polymer({
-    is: 'gr-file-list',
-
+  /**
+    * @appliesMixin Gerrit.AsyncForeachMixin
+    * @appliesMixin Gerrit.DomUtilMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.PathListMixin
+    */
+  class GrFileList extends Polymer.mixinBehaviors( [
+    Gerrit.AsyncForeachBehavior,
+    Gerrit.DomUtilBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.PathListBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-file-list'; }
     /**
      * Fired when a draft refresh should get triggered
      *
      * @event reload-drafts
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      patchRange: Object,
-      patchNum: String,
-      changeNum: String,
-      /** @type {?} */
-      changeComments: Object,
-      drafts: Object,
-      revisions: Array,
-      projectConfig: Object,
-      selectedIndex: {
-        type: Number,
-        notify: true,
-      },
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      /** @type {?} */
-      change: Object,
-      diffViewMode: {
-        type: String,
-        notify: true,
-        observer: '_updateDiffPreferences',
-      },
-      editMode: {
-        type: Boolean,
-        observer: '_editModeChanged',
-      },
-      filesExpanded: {
-        type: String,
-        value: GrFileListConstants.FilesExpandedState.NONE,
-        notify: true,
-      },
-      _filesByPath: Object,
-      _files: {
-        type: Array,
-        observer: '_filesChanged',
-        value() { return []; },
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-      _reviewed: {
-        type: Array,
-        value() { return []; },
-      },
-      diffPrefs: {
-        type: Object,
-        notify: true,
-        observer: '_updateDiffPreferences',
-      },
-      /** @type {?} */
-      _userPrefs: Object,
-      _showInlineDiffs: Boolean,
-      numFilesShown: {
-        type: Number,
-        notify: true,
-      },
-      /** @type {?} */
-      _patchChange: {
-        type: Object,
-        computed: '_calculatePatchChange(_files)',
-      },
-      fileListIncrement: Number,
-      _hideChangeTotals: {
-        type: Boolean,
-        computed: '_shouldHideChangeTotals(_patchChange)',
-      },
-      _hideBinaryChangeTotals: {
-        type: Boolean,
-        computed: '_shouldHideBinaryChangeTotals(_patchChange)',
-      },
+        patchRange: Object,
+        patchNum: String,
+        changeNum: String,
+        /** @type {?} */
+        changeComments: Object,
+        drafts: Object,
+        revisions: Array,
+        projectConfig: Object,
+        selectedIndex: {
+          type: Number,
+          notify: true,
+        },
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
+        /** @type {?} */
+        change: Object,
+        diffViewMode: {
+          type: String,
+          notify: true,
+          observer: '_updateDiffPreferences',
+        },
+        editMode: {
+          type: Boolean,
+          observer: '_editModeChanged',
+        },
+        filesExpanded: {
+          type: String,
+          value: GrFileListConstants.FilesExpandedState.NONE,
+          notify: true,
+        },
+        _filesByPath: Object,
+        _files: {
+          type: Array,
+          observer: '_filesChanged',
+          value() { return []; },
+        },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+        _reviewed: {
+          type: Array,
+          value() { return []; },
+        },
+        diffPrefs: {
+          type: Object,
+          notify: true,
+          observer: '_updateDiffPreferences',
+        },
+        /** @type {?} */
+        _userPrefs: Object,
+        _showInlineDiffs: Boolean,
+        numFilesShown: {
+          type: Number,
+          notify: true,
+        },
+        /** @type {?} */
+        _patchChange: {
+          type: Object,
+          computed: '_calculatePatchChange(_files)',
+        },
+        fileListIncrement: Number,
+        _hideChangeTotals: {
+          type: Boolean,
+          computed: '_shouldHideChangeTotals(_patchChange)',
+        },
+        _hideBinaryChangeTotals: {
+          type: Boolean,
+          computed: '_shouldHideBinaryChangeTotals(_patchChange)',
+        },
 
-      _shownFiles: {
-        type: Array,
-        computed: '_computeFilesShown(numFilesShown, _files)',
-      },
+        _shownFiles: {
+          type: Array,
+          computed: '_computeFilesShown(numFilesShown, _files)',
+        },
 
-      /**
+        /**
        * The amount of files added to the shown files list the last time it was
        * updated. This is used for reporting the average render time.
        */
-      _reportinShownFilesIncrement: Number,
+        _reportinShownFilesIncrement: Number,
 
-      _expandedFilePaths: {
-        type: Array,
-        value() { return []; },
-      },
-      _displayLine: Boolean,
-      _loading: {
-        type: Boolean,
-        observer: '_loadingChanged',
-      },
-      /** @type {Gerrit.LayoutStats|undefined} */
-      _sizeBarLayout: {
-        type: Object,
-        computed: '_computeSizeBarLayout(_shownFiles.*)',
-      },
+        _expandedFilePaths: {
+          type: Array,
+          value() { return []; },
+        },
+        _displayLine: Boolean,
+        _loading: {
+          type: Boolean,
+          observer: '_loadingChanged',
+        },
+        /** @type {Gerrit.LayoutStats|undefined} */
+        _sizeBarLayout: {
+          type: Object,
+          computed: '_computeSizeBarLayout(_shownFiles.*)',
+        },
 
-      _showSizeBars: {
-        type: Boolean,
-        value: true,
-        computed: '_computeShowSizeBars(_userPrefs)',
-      },
+        _showSizeBars: {
+          type: Boolean,
+          value: true,
+          computed: '_computeShowSizeBars(_userPrefs)',
+        },
 
-      /** @type {Function} */
-      _cancelForEachDiff: Function,
+        /** @type {Function} */
+        _cancelForEachDiff: Function,
 
-      _showDynamicColumns: {
-        type: Boolean,
-        computed: '_computeShowDynamicColumns(_dynamicHeaderEndpoints, ' +
+        _showDynamicColumns: {
+          type: Boolean,
+          computed: '_computeShowDynamicColumns(_dynamicHeaderEndpoints, ' +
                   '_dynamicContentEndpoints, _dynamicSummaryEndpoints)',
-      },
-      /** @type {Array<string>} */
-      _dynamicHeaderEndpoints: {
-        type: Array,
-      },
-      /** @type {Array<string>} */
-      _dynamicContentEndpoints: {
-        type: Array,
-      },
-      /** @type {Array<string>} */
-      _dynamicSummaryEndpoints: {
-        type: Array,
-      },
-    },
+        },
+        /** @type {Array<string>} */
+        _dynamicHeaderEndpoints: {
+          type: Array,
+        },
+        /** @type {Array<string>} */
+        _dynamicContentEndpoints: {
+          type: Array,
+        },
+        /** @type {Array<string>} */
+        _dynamicSummaryEndpoints: {
+          type: Array,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.AsyncForeachBehavior,
-      Gerrit.DomUtilBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.PathListBehavior,
-    ],
-
-    observers: [
-      '_expandedPathsChanged(_expandedFilePaths.splices)',
-      '_computeFiles(_filesByPath, changeComments, patchRange, _reviewed, ' +
+    static get observers() {
+      return [
+        '_expandedPathsChanged(_expandedFilePaths.splices)',
+        '_computeFiles(_filesByPath, changeComments, patchRange, _reviewed, ' +
           '_loading)',
-    ],
+      ];
+    }
 
-    keyBindings: {
-      esc: '_handleEscKey',
-    },
+    get keyBindings() {
+      return {
+        esc: '_handleEscKey',
+      };
+    }
 
     keyboardShortcuts() {
       return {
@@ -221,12 +234,16 @@
         [this.Shortcut.EXPAND_ALL_COMMENT_THREADS]: null,
         [this.Shortcut.COLLAPSE_ALL_COMMENT_THREADS]: null,
       };
-    },
-    listeners: {
-      keydown: '_scopedKeydownHandler',
-    },
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('keydown',
+          e => this._scopedKeydownHandler(e));
+    }
 
     attached() {
+      super.attached();
       Gerrit.awaitPluginsLoaded().then(() => {
         this._dynamicHeaderEndpoints = Gerrit._endpoints.getDynamicEndpoints(
             'change-view-file-list-header');
@@ -246,11 +263,12 @@
               'Different number of dynamic file-list headers and summary.');
         }
       });
-    },
+    }
 
     detached() {
+      super.detached();
       this._cancelDiffs();
-    },
+    }
 
     /**
      * Iron-a11y-keys-behavior catches keyboard events globally. Some keyboard
@@ -264,7 +282,7 @@
         // Enter.
         this._handleOpenFile(e);
       }
-    },
+    }
 
     reload() {
       if (!this.changeNum || !this.patchRange.patchNum) {
@@ -302,23 +320,23 @@
         this._detectChromiteButler();
         this.$.reporting.fileListDisplayed();
       });
-    },
+    }
 
     _detectChromiteButler() {
       const hasButler = !!document.getElementById('butler-suggested-owners');
       if (hasButler) {
         this.$.reporting.reportExtension('butler');
       }
-    },
+    }
 
     get diffs() {
       return Array.from(
           Polymer.dom(this.root).querySelectorAll('gr-diff-host'));
-    },
+    }
 
     openDiffPrefs() {
       this.$.diffPreferencesDialog.open();
-    },
+    }
 
     _calculatePatchChange(files) {
       const magicFilesExcluded = files.filter(files => {
@@ -343,15 +361,15 @@
         };
       }, {inserted: 0, deleted: 0, size_delta_inserted: 0,
         size_delta_deleted: 0, total_size: 0});
-    },
+    }
 
     _getDiffPreferences() {
       return this.$.restAPI.getDiffPreferences();
-    },
+    }
 
     _getPreferences() {
       return this.$.restAPI.getPreferences();
-    },
+    }
 
     _togglePathExpanded(path) {
       // Is the path in the list of expanded diffs? IF so remove it, otherwise
@@ -362,11 +380,11 @@
       } else {
         this.splice('_expandedFilePaths', pathIndex, 1);
       }
-    },
+    }
 
     _togglePathExpandedByIndex(index) {
       this._togglePathExpanded(this._files[index].__path);
-    },
+    }
 
     _updateDiffPreferences() {
       if (!this.diffs.length) { return; }
@@ -374,14 +392,14 @@
       this.$.reporting.time(EXPAND_ALL_TIMING_LABEL);
       this._renderInOrder(this._expandedFilePaths, this.diffs,
           this._expandedFilePaths.length);
-    },
+    }
 
     _forEachDiff(fn) {
       const diffs = this.diffs;
       for (let i = 0; i < diffs.length; i++) {
         fn(diffs[i]);
       }
-    },
+    }
 
     expandAllDiffs() {
       this._showInlineDiffs = true;
@@ -398,7 +416,7 @@
       }
 
       this.splice(...['_expandedFilePaths', 0, 0].concat(newPaths));
-    },
+    }
 
     collapseAllDiffs() {
       this._showInlineDiffs = false;
@@ -406,7 +424,7 @@
       this.filesExpanded = this._computeExpandedFiles(
           this._expandedFilePaths.length, this._files.length);
       this.$.diffCursor.handleDiffUpdate();
-    },
+    }
 
     /**
      * Computes a string with the number of comments and unresolved comments.
@@ -433,7 +451,7 @@
           (commentString && unresolvedString ? ' ' : '') +
           // Add parentheses around unresolved if it exists.
           (unresolvedString ? `(${unresolvedString})` : '');
-    },
+    }
 
     /**
      * Computes a string with the number of drafts.
@@ -448,7 +466,7 @@
           changeComments.computeDraftCount(patchRange.basePatchNum, path) +
           changeComments.computeDraftCount(patchRange.patchNum, path);
       return GrCountStringFormatter.computePluralString(draftCount, 'draft');
-    },
+    }
 
     /**
      * Computes a shortened string with the number of drafts.
@@ -463,7 +481,7 @@
           changeComments.computeDraftCount(patchRange.basePatchNum, path) +
           changeComments.computeDraftCount(patchRange.patchNum, path);
       return GrCountStringFormatter.computeShortString(draftCount, 'd');
-    },
+    }
 
     /**
      * Computes a shortened string with the number of comments.
@@ -478,7 +496,7 @@
           changeComments.computeCommentCount(patchRange.basePatchNum, path) +
           changeComments.computeCommentCount(patchRange.patchNum, path);
       return GrCountStringFormatter.computeShortString(commentCount, 'c');
-    },
+    }
 
     /**
      * @param {string} path
@@ -495,27 +513,27 @@
       }
 
       this._saveReviewedState(path, reviewed);
-    },
+    }
 
     _saveReviewedState(path, reviewed) {
       return this.$.restAPI.saveFileReviewed(this.changeNum,
           this.patchRange.patchNum, path, reviewed);
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _getReviewedFiles() {
       if (this.editMode) { return Promise.resolve([]); }
       return this.$.restAPI.getReviewedFiles(this.changeNum,
           this.patchRange.patchNum);
-    },
+    }
 
     _getFiles() {
       return this.$.restAPI.getChangeOrEditFiles(
           this.changeNum, this.patchRange);
-    },
+    }
 
     /**
      * The closure compiler doesn't realize this.specialFilePathCompare is
@@ -534,7 +552,7 @@
         files.push(info);
       }
       return files;
-    },
+    }
 
     /**
      * Handle all events from the file list dom-repeat so event handleers don't
@@ -564,7 +582,7 @@
 
       e.preventDefault();
       this._togglePathExpanded(path);
-    },
+    }
 
     _handleLeftPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e) || this._noDiffsExpanded()) {
@@ -573,7 +591,7 @@
 
       e.preventDefault();
       this.$.diffCursor.moveLeft();
-    },
+    }
 
     _handleRightPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e) || this._noDiffsExpanded()) {
@@ -582,7 +600,7 @@
 
       e.preventDefault();
       this.$.diffCursor.moveRight();
-    },
+    }
 
     _handleToggleInlineDiff(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -591,14 +609,14 @@
 
       e.preventDefault();
       this._togglePathExpandedByIndex(this.$.fileCursor.index);
-    },
+    }
 
     _handleToggleAllInlineDiffs(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
 
       e.preventDefault();
       this._toggleInlineDiffs();
-    },
+    }
 
     _handleCursorNext(e) {
       if (this.shouldSuppressKeyboardShortcut(e) || this.modifierPressed(e)) {
@@ -616,7 +634,7 @@
         this.$.fileCursor.next();
         this.selectedIndex = this.$.fileCursor.index;
       }
-    },
+    }
 
     _handleCursorPrev(e) {
       if (this.shouldSuppressKeyboardShortcut(e) || this.modifierPressed(e)) {
@@ -634,20 +652,14 @@
         this.$.fileCursor.previous();
         this.selectedIndex = this.$.fileCursor.index;
       }
-    },
+    }
 
     _handleNewComment(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
           this.modifierPressed(e)) { return; }
-
-      const isRangeSelected = this.diffs.some(diff => {
-        return diff.isRangeSelected();
-      }, this);
-      if (!isRangeSelected) {
-        e.preventDefault();
-        this._addDraftAtTarget();
-      }
-    },
+      e.preventDefault();
+      this.$.diffCursor.createCommentInPlace();
+    }
 
     _handleOpenLastFile(e) {
       // Check for meta key to avoid overriding native chrome shortcut.
@@ -656,7 +668,7 @@
 
       e.preventDefault();
       this._openSelectedFile(this._files.length - 1);
-    },
+    }
 
     _handleOpenFirstFile(e) {
       // Check for meta key to avoid overriding native chrome shortcut.
@@ -665,7 +677,7 @@
 
       e.preventDefault();
       this._openSelectedFile(0);
-    },
+    }
 
     _handleOpenFile(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -678,7 +690,7 @@
       }
 
       this._openSelectedFile();
-    },
+    }
 
     _handleNextChunk(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -693,7 +705,7 @@
       } else {
         this.$.diffCursor.moveToNextChunk();
       }
-    },
+    }
 
     _handlePrevChunk(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -708,7 +720,7 @@
       } else {
         this.$.diffCursor.moveToPreviousChunk();
       }
-    },
+    }
 
     _handleToggleFileReviewed(e) {
       if (this.shouldSuppressKeyboardShortcut(e) || this.modifierPressed(e)) {
@@ -718,7 +730,7 @@
       e.preventDefault();
       if (!this._files[this.$.fileCursor.index]) { return; }
       this._reviewFile(this._files[this.$.fileCursor.index].__path);
-    },
+    }
 
     _handleToggleLeftPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -727,7 +739,7 @@
       this._forEachDiff(diff => {
         diff.toggleLeftDiff();
       });
-    },
+    }
 
     _toggleInlineDiffs() {
       if (this._showInlineDiffs) {
@@ -735,13 +747,13 @@
       } else {
         this.expandAllDiffs();
       }
-    },
+    }
 
     _openCursorFile() {
       const diff = this.$.diffCursor.getTargetDiffElement();
       Gerrit.Nav.navigateToDiff(this.change, diff.path,
           diff.patchRange.patchNum, this.patchRange.basePatchNum);
-    },
+    }
 
     /**
      * @param {number=} opt_index
@@ -754,7 +766,7 @@
       Gerrit.Nav.navigateToDiff(this.change,
           this._files[this.$.fileCursor.index].__path, this.patchRange.patchNum,
           this.patchRange.basePatchNum);
-    },
+    }
 
     _addDraftAtTarget() {
       const diff = this.$.diffCursor.getTargetDiffElement();
@@ -762,20 +774,20 @@
       if (diff && target) {
         diff.addDraftAtLine(target);
       }
-    },
+    }
 
     _shouldHideChangeTotals(_patchChange) {
       return _patchChange.inserted === 0 && _patchChange.deleted === 0;
-    },
+    }
 
     _shouldHideBinaryChangeTotals(_patchChange) {
       return _patchChange.size_delta_inserted === 0 &&
           _patchChange.size_delta_deleted === 0;
-    },
+    }
 
     _computeFileStatus(status) {
       return status || 'M';
-    },
+    }
 
     _computeDiffURL(change, patchNum, basePatchNum, path, editMode) {
       // Polymer 2: check for undefined
@@ -790,7 +802,7 @@
             basePatchNum);
       }
       return Gerrit.Nav.getUrlForDiff(change, path, patchNum, basePatchNum);
-    },
+    }
 
     _formatBytes(bytes) {
       if (bytes == 0) return '+/-0 B';
@@ -802,7 +814,7 @@
       const prepend = bytes > 0 ? '+' : '';
       return prepend + parseFloat((bytes / Math.pow(bits, exponent))
           .toFixed(decimals)) + ' ' + sizes[exponent];
-    },
+    }
 
     _formatPercentage(size, delta) {
       const oldSize = size - delta;
@@ -811,12 +823,12 @@
 
       const percentage = Math.round(Math.abs(delta * 100 / oldSize));
       return '(' + (delta > 0 ? '+' : '-') + percentage + '%)';
-    },
+    }
 
     _computeBinaryClass(delta) {
       if (delta === 0) { return; }
       return delta >= 0 ? 'added' : 'removed';
-    },
+    }
 
     /**
      * @param {string} baseClass
@@ -831,16 +843,16 @@
         classes.push('invisible');
       }
       return classes.join(' ');
-    },
+    }
 
     _computePathClass(path, expandedFilesRecord) {
       return this._isFileExpanded(path, expandedFilesRecord) ? 'expanded' : '';
-    },
+    }
 
     _computeShowHideIcon(path, expandedFilesRecord) {
       return this._isFileExpanded(path, expandedFilesRecord) ?
-          'gr-icons:expand-less' : 'gr-icons:expand-more';
-    },
+        'gr-icons:expand-less' : 'gr-icons:expand-more';
+    }
 
     _computeFiles(filesByPath, changeComments, patchRange, reviewed, loading) {
       // Polymer 2: check for undefined
@@ -870,7 +882,7 @@
       }
 
       this._files = this._normalizeChangeFilesResponse(files);
-    },
+    }
 
     _computeFilesShown(numFilesShown, files) {
       // Polymer 2: check for undefined
@@ -879,7 +891,7 @@
       }
 
       const previousNumFilesShown = this._shownFiles ?
-          this._shownFiles.length : 0;
+        this._shownFiles.length : 0;
 
       const filesShown = files.slice(0, numFilesShown);
       this.fire('files-shown-changed', {length: filesShown.length});
@@ -894,13 +906,13 @@
           Math.max(0, filesShown.length - previousNumFilesShown);
 
       return filesShown;
-    },
+    }
 
     _updateDiffCursor() {
       // Overwrite the cursor's list of diffs:
       this.$.diffCursor.splice(
           ...['diffs', 0, this.$.diffCursor.diffs.length].concat(this.diffs));
-    },
+    }
 
     _filesChanged() {
       if (this._files && this._files.length > 0) {
@@ -910,41 +922,41 @@
         this.$.fileCursor.stops = files;
         this.$.fileCursor.setCursorAtIndex(this.selectedIndex, true);
       }
-    },
+    }
 
     _incrementNumFilesShown() {
       this.numFilesShown += this.fileListIncrement;
-    },
+    }
 
     _computeFileListControlClass(numFilesShown, files) {
       return numFilesShown >= files.length ? 'invisible' : '';
-    },
+    }
 
     _computeIncrementText(numFilesShown, files) {
       if (!files) { return ''; }
       const text =
           Math.min(this.fileListIncrement, files.length - numFilesShown);
       return 'Show ' + text + ' more';
-    },
+    }
 
     _computeShowAllText(files) {
       if (!files) { return ''; }
       return 'Show all ' + files.length + ' files';
-    },
+    }
 
     _computeWarnShowAll(files) {
       return files.length > WARN_SHOW_ALL_THRESHOLD;
-    },
+    }
 
     _computeShowAllWarning(files) {
       if (!this._computeWarnShowAll(files)) { return ''; }
       return 'Warning: showing all ' + files.length +
           ' files may take several seconds.';
-    },
+    }
 
     _showAllFiles() {
       this.numFilesShown = this._files.length;
-    },
+    }
 
     _computePatchSetDescription(revisions, patchNum) {
       // Polymer 2: check for undefined
@@ -954,8 +966,8 @@
 
       const rev = this.getRevisionByPatchNum(revisions, patchNum);
       return (rev && rev.description) ?
-          rev.description.substring(0, PATCH_DESC_MAX_LENGTH) : '';
-    },
+        rev.description.substring(0, PATCH_DESC_MAX_LENGTH) : '';
+    }
 
     /**
      * Get a descriptive label for use in the status indicator's tooltip and
@@ -966,17 +978,17 @@
     _computeFileStatusLabel(status) {
       const statusCode = this._computeFileStatus(status);
       return FileStatus.hasOwnProperty(statusCode) ?
-          FileStatus[statusCode] : 'Status Unknown';
-    },
+        FileStatus[statusCode] : 'Status Unknown';
+    }
 
     _isFileExpanded(path, expandedFilesRecord) {
       return expandedFilesRecord.base.includes(path);
-    },
+    }
 
     _onLineSelected(e, detail) {
       this.$.diffCursor.moveToLineNumber(detail.number, detail.side,
           detail.path);
-    },
+    }
 
     _computeExpandedFiles(expandedCount, totalCount) {
       if (expandedCount === 0) {
@@ -985,7 +997,7 @@
         return GrFileListConstants.FilesExpandedState.ALL;
       }
       return GrFileListConstants.FilesExpandedState.SOME;
-    },
+    }
 
     /**
      * Handle splices to the list of expanded file paths. If there are any new
@@ -998,7 +1010,7 @@
       // Clear content for any diffs that are not open so if they get re-opened
       // the stale content does not flash before it is cleared and reloaded.
       const collapsedDiffs = this.diffs.filter(diff =>
-          this._expandedFilePaths.indexOf(diff.path) === -1);
+        this._expandedFilePaths.indexOf(diff.path) === -1);
       this._clearCollapsedDiffs(collapsedDiffs);
 
       if (!record) { return; } // Happens after "Collapse all" clicked.
@@ -1008,9 +1020,9 @@
 
       // Find the paths introduced by the new index splices:
       const newPaths = record.indexSplices
-            .map(splice => splice.object.slice(
-                splice.index, splice.index + splice.addedCount))
-            .reduce((acc, paths) => acc.concat(paths), []);
+          .map(splice => splice.object.slice(
+              splice.index, splice.index + splice.addedCount))
+          .reduce((acc, paths) => acc.concat(paths), []);
 
       // Required so that the newly created diff view is included in this.diffs.
       Polymer.dom.flush();
@@ -1023,14 +1035,14 @@
 
       this._updateDiffCursor();
       this.$.diffCursor.handleDiffUpdate();
-    },
+    }
 
     _clearCollapsedDiffs(collapsedDiffs) {
       for (const diff of collapsedDiffs) {
         diff.cancel();
         diff.clearDiffContent();
       }
-    },
+    }
 
     /**
      * Given an array of paths and a NodeList of diff elements, render the diff
@@ -1071,13 +1083,13 @@
           this.$.diffCursor.handleDiffUpdate();
         });
       });
-    },
+    }
 
     /** Cancel the rendering work of every diff in the list */
     _cancelDiffs() {
       if (this._cancelForEachDiff) { this._cancelForEachDiff(); }
       this._forEachDiff(d => d.cancel());
-    },
+    }
 
     /**
      * In the given NodeList of diff elements, find the diff for the given path.
@@ -1091,7 +1103,7 @@
           return diffElements[i];
         }
       }
-    },
+    }
 
     /**
      * Reset the comments of a modified thread
@@ -1128,14 +1140,14 @@
       });
       Polymer.dom.flush();
       return;
-    },
+    }
 
     _handleEscKey(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
           this.modifierPressed(e)) { return; }
       e.preventDefault();
       this._displayLine = false;
-    },
+    }
 
     /**
      * Update the loading class for the file list rows. The update is inside a
@@ -1149,19 +1161,19 @@
         // this way, the gray loading style is not shown on initial loads.
         this.classList.toggle('loading', loading && !!this._files.length);
       }, LOADING_DEBOUNCE_INTERVAL);
-    },
+    }
 
     _editModeChanged(editMode) {
       this.classList.toggle('editMode', editMode);
-    },
+    }
 
     _computeReviewedClass(isReviewed) {
       return isReviewed ? 'isReviewed' : '';
-    },
+    }
 
     _computeReviewedText(isReviewed) {
       return isReviewed ? 'MARK UNREVIEWED' : 'MARK REVIEWED';
-    },
+    }
 
     /**
      * Given a file path, return whether that path should have visible size bars
@@ -1171,7 +1183,7 @@
      */
     _showBarsForPath(path) {
       return path !== this.COMMIT_MESSAGE_PATH && path !== this.MERGE_LIST_PATH;
-    },
+    }
 
     /**
      * Compute size bar layout values from the file list.
@@ -1205,7 +1217,7 @@
         stats.deletionOffset = stats.maxAdditionWidth + SIZE_BAR_GAP_WIDTH;
       }
       return stats;
-    },
+    }
 
     /**
      * Get the width of the addition bar for a file.
@@ -1222,7 +1234,7 @@
       const width =
           stats.maxAdditionWidth * file.lines_inserted / stats.maxInserted;
       return width === 0 ? 0 : Math.max(SIZE_BAR_MIN_WIDTH, width);
-    },
+    }
 
     /**
      * Get the x-offset of the addition bar for a file.
@@ -1233,7 +1245,7 @@
     _computeBarAdditionX(file, stats) {
       return stats.maxAdditionWidth -
           this._computeBarAdditionWidth(file, stats);
-    },
+    }
 
     /**
      * Get the width of the deletion bar for a file.
@@ -1250,7 +1262,7 @@
       const width =
           stats.maxDeletionWidth * file.lines_deleted / stats.maxDeleted;
       return width === 0 ? 0 : Math.max(SIZE_BAR_MIN_WIDTH, width);
-    },
+    }
 
     /**
      * Get the x-offset of the deletion bar for a file.
@@ -1259,11 +1271,11 @@
      */
     _computeBarDeletionX(stats) {
       return stats.deletionOffset;
-    },
+    }
 
     _computeShowSizeBars(userPrefs) {
       return !!userPrefs.size_bar_in_change_table;
-    },
+    }
 
     _computeSizeBarsClass(showSizeBars, path) {
       let hideClass = '';
@@ -1273,7 +1285,7 @@
         hideClass = 'invisible';
       }
       return `sizeBars desktop ${hideClass}`;
-    },
+    }
 
     /**
      * Shows registered dynamic columns iff the 'header', 'content' and
@@ -1286,7 +1298,7 @@
       return headerEndpoints && contentEndpoints && summaryEndpoints &&
              headerEndpoints.length === contentEndpoints.length &&
              headerEndpoints.length === summaryEndpoints.length;
-    },
+    }
 
     /**
      * Returns true if none of the inline diffs have been expanded.
@@ -1294,7 +1306,7 @@
      */
     _noDiffsExpanded() {
       return this.filesExpanded === GrFileListConstants.FilesExpandedState.NONE;
-    },
+    }
 
     /**
      * Method to call via binding when each file list row is rendered. This
@@ -1311,7 +1323,7 @@
         }, 1);
       }
       return '';
-    },
+    }
 
     _reviewedTitle(reviewed) {
       if (reviewed) {
@@ -1319,12 +1331,14 @@
       }
 
       return 'Mark as reviewed (shortcut: r)';
-    },
+    }
 
     _handleReloadingDiffPreference() {
       this._getDiffPreferences().then(prefs => {
         this.diffPrefs = prefs;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrFileList.is, GrFileList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_test.html b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_test.html
index 122291e..0d25846 100644
--- a/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-file-list/gr-file-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-file-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -440,10 +440,10 @@
               '/COMMIT_MSG', 'comment'), '3 comments (1 unresolved)');
       assert.equal(
           element._computeCommentsStringMobile(element.changeComments, parentTo1
-          , '/COMMIT_MSG'), '2c');
+              , '/COMMIT_MSG'), '2c');
       assert.equal(
           element._computeCommentsStringMobile(element.changeComments, _1To2
-          , '/COMMIT_MSG'), '3c');
+              , '/COMMIT_MSG'), '3c');
       assert.equal(
           element._computeDraftsString(element.changeComments, parentTo1,
               'unresolved.file'), '1 draft');
@@ -639,7 +639,7 @@
 
         assert(navStub.lastCall.calledWith(element.change,
             'file_added_in_rev2.txt', '2'),
-            'Should navigate to /c/42/2/file_added_in_rev2.txt');
+        'Should navigate to /c/42/2/file_added_in_rev2.txt');
 
         MockInteractions.pressAndReleaseKeyOn(element, 75, null, 'k');
         MockInteractions.pressAndReleaseKeyOn(element, 75, null, 'k');
@@ -647,9 +647,10 @@
         assert.equal(element.$.fileCursor.index, 0);
         assert.equal(element.selectedIndex, 0);
 
-        sandbox.stub(element, '_addDraftAtTarget');
+        const createCommentInPlaceStub = sandbox.stub(element.$.diffCursor,
+            'createCommentInPlace');
         MockInteractions.pressAndReleaseKeyOn(element, 67, null, 'c');
-        assert.isTrue(element._addDraftAtTarget.called);
+        assert.isTrue(createCommentInPlaceStub.called);
       });
 
       test('i key shows/hides selected inline diff', () => {
@@ -1639,7 +1640,7 @@
 
       element.set('_filesByPath', _filesByPath);
       flushAsynchronousOperations();
-       // Navigates when a file is selected.
+      // Navigates when a file is selected.
       element._openSelectedFile();
       assert.isTrue(navStub.called);
     });
@@ -1701,7 +1702,7 @@
       const editControls =
           Array.from(
               Polymer.dom(element.root)
-              .querySelectorAll('.row:not(.header-row)'))
+                  .querySelectorAll('.row:not(.header-row)'))
               .map(row => row.querySelector('gr-edit-file-controls'));
       assert.isTrue(editControls[0].classList.contains('invisible'));
     });
diff --git a/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog.js b/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog.js
index 4b8ce22..f0cba0b 100644
--- a/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog.js
@@ -17,36 +17,40 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-included-in-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrIncludedInDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-included-in-dialog'; }
     /**
      * Fired when the user presses the close button.
      *
      * @event close
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      changeNum: {
-        type: Object,
-        observer: '_resetData',
-      },
-      /** @type {?} */
-      _includedIn: Object,
-      _loaded: {
-        type: Boolean,
-        value: false,
-      },
-      _filterText: {
-        type: String,
-        value: '',
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+        changeNum: {
+          type: Object,
+          observer: '_resetData',
+        },
+        /** @type {?} */
+        _includedIn: Object,
+        _loaded: {
+          type: Boolean,
+          value: false,
+        },
+        _filterText: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     loadData() {
       if (!this.changeNum) { return; }
@@ -57,12 +61,12 @@
             this._includedIn = configs;
             this._loaded = true;
           });
-    },
+    }
 
     _resetData() {
       this._includedIn = null;
       this._loaded = false;
-    },
+    }
 
     _computeGroups(includedIn, filterText) {
       if (!includedIn) { return []; }
@@ -83,22 +87,24 @@
         }
       }
       return groups.filter(g => g.items.length);
-    },
+    }
 
     _handleCloseTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('close', null, {bubbles: false});
-    },
+    }
 
     _computeLoadingClass(loaded) {
       return loaded ? 'loading loaded' : 'loading';
-    },
+    }
 
     _onFilterChanged() {
       this.debounce('filter-change', () => {
         this._filterText = this.$.filterInput.bindValue;
       }, 100);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrIncludedInDialog.is, GrIncludedInDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog_test.html b/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog_test.html
index 68c77e6..b97e0b4 100644
--- a/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-included-in-dialog/gr-included-in-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-included-in-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.html b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.html
index 220546b..46fd227 100644
--- a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.html
+++ b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.html
@@ -23,7 +23,9 @@
 
 <dom-module id="gr-label-score-row">
   <template>
-    <style include="gr-voting-styles"></style>
+    <style include="gr-voting-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       .labelContainer {
         align-items: center;
@@ -109,7 +111,7 @@
         </template>
         <iron-selector
             id="labelSelector"
-            attr-for-selected="value"
+            attr-for-selected="data-value"
             selected="[[_computeLabelValue(labels, permittedLabels, label)]]"
             hidden$="[[!_computeAnyPermittedLabelValues(permittedLabels, label.name)]]"
             on-selected-item-changed="_setSelectedValueText">
@@ -119,8 +121,8 @@
             <gr-button
                 class$="[[_computeButtonClass(value, index, _items.length)]]"
                 has-tooltip
-                name="[[label.name]]"
-                value$="[[value]]"
+                data-name$="[[label.name]]"
+                data-value$="[[value]]"
                 title$="[[_computeLabelValueTitle(labels, label.name, value)]]">
               [[value]]</gr-button>
           </template>
diff --git a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.js b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.js
index 0b888c4..abfe469 100644
--- a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.js
+++ b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row.js
@@ -17,56 +17,59 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-label-score-row',
-
+  class GrLabelScoreRow extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-label-score-row'; }
     /**
      * Fired when any label is changed.
      *
      * @event labels-changed
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * @type {{ name: string }}
        */
-      label: Object,
-      labels: Object,
-      name: {
-        type: String,
-        reflectToAttribute: true,
-      },
-      permittedLabels: Object,
-      labelValues: Object,
-      _selectedValueText: {
-        type: String,
-        value: 'No value selected',
-      },
-      _items: {
-        type: Array,
-        computed: '_computePermittedLabelValues(permittedLabels, label.name)',
-      },
-    },
+        label: Object,
+        labels: Object,
+        name: {
+          type: String,
+          reflectToAttribute: true,
+        },
+        permittedLabels: Object,
+        labelValues: Object,
+        _selectedValueText: {
+          type: String,
+          value: 'No value selected',
+        },
+        _items: {
+          type: Array,
+          computed: '_computePermittedLabelValues(permittedLabels, label.name)',
+        },
+      };
+    }
 
     get selectedItem() {
       if (!this._ironSelector) { return undefined; }
       return this._ironSelector.selectedItem;
-    },
+    }
 
     get selectedValue() {
       if (!this._ironSelector) { return undefined; }
       return this._ironSelector.selected;
-    },
+    }
 
     setSelectedValue(value) {
       // The selector may not be present if it’s not at the latest patch set.
       if (!this._ironSelector) { return; }
       this._ironSelector.select(value);
-    },
+    }
 
     get _ironSelector() {
       return this.$ && this.$.labelSelector;
-    },
+    }
 
     _computeBlankItems(permittedLabels, label, side) {
       if (!permittedLabels || !permittedLabels[label] ||
@@ -82,7 +85,7 @@
       const endPosition = this.labelValues[parseInt(
           permittedLabels[label][permittedLabels[label].length - 1], 10)];
       return new Array(Object.keys(this.labelValues).length - endPosition - 1);
-    },
+    }
 
     _getLabelValue(labels, permittedLabels, label) {
       if (label.value) {
@@ -93,7 +96,7 @@
         return permittedLabels[label.name].find(
             value => parseInt(value, 10) === labels[label.name].default_value);
       }
-    },
+    }
 
     _computeButtonClass(value, index, totalItems) {
       const classes = [];
@@ -114,7 +117,7 @@
       }
 
       return classes.join(' ');
-    },
+    }
 
     _computeLabelValue(labels, permittedLabels, label) {
       if ([labels, permittedLabels, label].some(arg => arg === undefined)) {
@@ -123,7 +126,7 @@
       if (!labels[label.name]) { return null; }
       const labelValue = this._getLabelValue(labels, permittedLabels, label);
       const len = permittedLabels[label.name] != null ?
-          permittedLabels[label.name].length : 0;
+        permittedLabels[label.name].length : 0;
       for (let i = 0; i < len; i++) {
         const val = permittedLabels[label.name][i];
         if (val === labelValue) {
@@ -131,7 +134,7 @@
         }
       }
       return null;
-    },
+    }
 
     _setSelectedValueText(e) {
       // Needed because when the selected item changes, it first changes to
@@ -140,22 +143,22 @@
       this._selectedValueText = e.target.selectedItem.getAttribute('title');
       // Needed to update the style of the selected button.
       this.updateStyles();
-      const name = e.target.selectedItem.name;
-      const value = e.target.selectedItem.getAttribute('value');
+      const name = e.target.selectedItem.dataset.name;
+      const value = e.target.selectedItem.dataset.value;
       this.dispatchEvent(new CustomEvent(
           'labels-changed',
           {detail: {name, value}, bubbles: true, composed: true}));
-    },
+    }
 
     _computeAnyPermittedLabelValues(permittedLabels, label) {
       return permittedLabels && permittedLabels.hasOwnProperty(label) &&
         permittedLabels[label].length;
-    },
+    }
 
     _computeHiddenClass(permittedLabels, label) {
       return !this._computeAnyPermittedLabelValues(permittedLabels, label) ?
-          'hidden' : '';
-    },
+        'hidden' : '';
+    }
 
     _computePermittedLabelValues(permittedLabels, label) {
       // Polymer 2: check for undefined
@@ -164,12 +167,14 @@
       }
 
       return permittedLabels[label];
-    },
+    }
 
     _computeLabelValueTitle(labels, label, value) {
       return labels[label] &&
         labels[label].values &&
         labels[label].values[value];
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLabelScoreRow.is, GrLabelScoreRow);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row_test.html b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row_test.html
index 519fbb8..e9c21bc 100644
--- a/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row_test.html
+++ b/polygerrit-ui/app/elements/change/gr-label-score-row/gr-label-score-row_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-label-score-row</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -110,7 +110,7 @@
       element.addEventListener('labels-changed', labelsChangedHandler);
       assert.ok(element.$.labelSelector);
       MockInteractions.tap(element.$$(
-          'gr-button[value="-1"]'));
+          'gr-button[data-value="-1"]'));
       flushAsynchronousOperations();
       assert.strictEqual(element.selectedValue, '-1');
       assert.strictEqual(element.selectedItem
@@ -167,7 +167,7 @@
 
     test('do not display tooltips on touch devices', () => {
       const verifiedBtn = element.$$(
-          'iron-selector > gr-button[value="-1"]');
+          'iron-selector > gr-button[data-value="-1"]');
 
       // On touch devices, tooltips should not be shown.
       verifiedBtn._isTouchDevice = true;
diff --git a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.js b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.js
index 5b498c2..2c164f1 100644
--- a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.js
+++ b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores.js
@@ -17,22 +17,29 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-label-scores',
+  class GrLabelScores extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-label-scores'; }
 
-    properties: {
-      _labels: {
-        type: Array,
-        computed: '_computeLabels(change.labels.*, account)',
-      },
-      permittedLabels: {
-        type: Object,
-        observer: '_computeColumns',
-      },
-      /** @type {?} */
-      change: Object,
-      _labelValues: Object,
-    },
+    static get properties() {
+      return {
+        _labels: {
+          type: Array,
+          computed: '_computeLabels(change.labels.*, account)',
+        },
+        permittedLabels: {
+          type: Object,
+          observer: '_computeColumns',
+        },
+        /** @type {?} */
+        change: Object,
+        /** @type {?} */
+        account: Object,
+
+        _labelValues: Object,
+      };
+    }
 
     getLabelValues() {
       const labels = {};
@@ -58,7 +65,7 @@
         }
       }
       return labels;
-    },
+    }
 
     _getStringLabelValue(labels, labelName, numberValue) {
       for (const k in labels[labelName].values) {
@@ -67,7 +74,7 @@
         }
       }
       return numberValue;
-    },
+    }
 
     _getVoteForAccount(labels, labelName, account) {
       const votes = labels[labelName];
@@ -80,7 +87,7 @@
         }
       }
       return null;
-    },
+    }
 
     _computeLabels(labelRecord, account) {
       // Polymer 2: check for undefined
@@ -96,7 +103,7 @@
           value: this._getVoteForAccount(labelsObj, key, this.account),
         };
       });
-    },
+    }
 
     _computeColumns(permittedLabels) {
       const labels = Object.keys(permittedLabels);
@@ -115,11 +122,11 @@
         values[orderedValues[i]] = i;
       }
       this._labelValues = values;
-    },
+    }
 
     _changeIsMerged(changeStatus) {
       return changeStatus === 'MERGED';
-    },
+    }
 
     /**
      * @param label {string|undefined}
@@ -133,6 +140,8 @@
 
       return permittedLabels.hasOwnProperty(label) &&
         permittedLabels[label].length ? 'access' : 'no-access';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLabelScores.is, GrLabelScores);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores_test.html b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores_test.html
index f986a58..4c489b7 100644
--- a/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores_test.html
+++ b/polygerrit-ui/app/elements/change/gr-label-scores/gr-label-scores_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-label-scores</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -123,7 +123,7 @@
       const labelName = 'Code-Review';
       assert.strictEqual(element._getVoteForAccount(
           element.change.labels, labelName, element.account),
-          '+1');
+      '+1');
     });
 
     test('_computeColumns', () => {
@@ -187,10 +187,10 @@
           {name: 'Verified', value: null}
       ]);
       element.set(['change', 'labels', 'Verified', 'all'],
-         [{_account_id: 123, value: 1}]);
+          [{_account_id: 123, value: 1}]);
       assert.deepEqual(element._labels, [
-          {name: 'Code-Review', value: null},
-          {name: 'Verified', value: '+1'},
+        {name: 'Code-Review', value: null},
+        {name: 'Verified', value: '+1'},
       ]);
     });
   });
diff --git a/polygerrit-ui/app/elements/change/gr-message/gr-message.html b/polygerrit-ui/app/elements/change/gr-message/gr-message.html
index da5eb39..fbd5d68d 100644
--- a/polygerrit-ui/app/elements/change/gr-message/gr-message.html
+++ b/polygerrit-ui/app/elements/change/gr-message/gr-message.html
@@ -31,7 +31,9 @@
 
 <dom-module id="gr-message">
   <template>
-    <style include="gr-voting-styles"></style>
+    <style include="gr-voting-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       :host {
         border-bottom: 1px solid var(--border-color);
diff --git a/polygerrit-ui/app/elements/change/gr-message/gr-message.js b/polygerrit-ui/app/elements/change/gr-message/gr-message.js
index 26e0cd3..7c1d66c 100644
--- a/polygerrit-ui/app/elements/change/gr-message/gr-message.js
+++ b/polygerrit-ui/app/elements/change/gr-message/gr-message.js
@@ -20,9 +20,15 @@
   const PATCH_SET_PREFIX_PATTERN = /^Patch Set \d+: /;
   const LABEL_TITLE_SCORE_PATTERN = /^([A-Za-z0-9-]+)([+-]\d+)$/;
 
-  Polymer({
-    is: 'gr-message',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrMessage extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-message'; }
     /**
      * Fired when this message's reply link is tapped.
      *
@@ -35,90 +41,93 @@
      * @event message-anchor-tap
      */
 
-    listeners: {
-      click: '_handleClick',
-    },
+    static get properties() {
+      return {
+        changeNum: Number,
+        /** @type {?} */
+        message: Object,
+        author: {
+          type: Object,
+          computed: '_computeAuthor(message)',
+        },
+        comments: {
+          type: Object,
+          observer: '_commentsChanged',
+        },
+        config: Object,
+        hideAutomated: {
+          type: Boolean,
+          value: false,
+        },
+        hidden: {
+          type: Boolean,
+          computed: '_computeIsHidden(hideAutomated, isAutomated)',
+          reflectToAttribute: true,
+        },
+        isAutomated: {
+          type: Boolean,
+          computed: '_computeIsAutomated(message)',
+        },
+        showAvatar: {
+          type: Boolean,
+          computed: '_computeShowAvatar(author, config)',
+        },
+        showOnBehalfOf: {
+          type: Boolean,
+          computed: '_computeShowOnBehalfOf(message)',
+        },
+        showReplyButton: {
+          type: Boolean,
+          computed: '_computeShowReplyButton(message, _loggedIn)',
+        },
+        projectName: {
+          type: String,
+          observer: '_projectNameChanged',
+        },
 
-    properties: {
-      changeNum: Number,
-      /** @type {?} */
-      message: Object,
-      author: {
-        type: Object,
-        computed: '_computeAuthor(message)',
-      },
-      comments: {
-        type: Object,
-        observer: '_commentsChanged',
-      },
-      config: Object,
-      hideAutomated: {
-        type: Boolean,
-        value: false,
-      },
-      hidden: {
-        type: Boolean,
-        computed: '_computeIsHidden(hideAutomated, isAutomated)',
-        reflectToAttribute: true,
-      },
-      isAutomated: {
-        type: Boolean,
-        computed: '_computeIsAutomated(message)',
-      },
-      showAvatar: {
-        type: Boolean,
-        computed: '_computeShowAvatar(author, config)',
-      },
-      showOnBehalfOf: {
-        type: Boolean,
-        computed: '_computeShowOnBehalfOf(message)',
-      },
-      showReplyButton: {
-        type: Boolean,
-        computed: '_computeShowReplyButton(message, _loggedIn)',
-      },
-      projectName: {
-        type: String,
-        observer: '_projectNameChanged',
-      },
-
-      /**
+        /**
        * A mapping from label names to objects representing the minimum and
        * maximum possible values for that label.
        */
-      labelExtremes: Object,
+        labelExtremes: Object,
 
-      /**
+        /**
        * @type {{ commentlinks: Array }}
        */
-      _projectConfig: Object,
-      // Computed property needed to trigger Polymer value observing.
-      _expanded: {
-        type: Object,
-        computed: '_computeExpanded(message.expanded)',
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _projectConfig: Object,
+        // Computed property needed to trigger Polymer value observing.
+        _expanded: {
+          type: Object,
+          computed: '_computeExpanded(message.expanded)',
+        },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get observers() {
+      return [
+        '_updateExpandedClass(message.expanded)',
+      ];
+    }
 
-    observers: [
-      '_updateExpandedClass(message.expanded)',
-    ],
+    created() {
+      super.created();
+      this.addEventListener('click',
+          e => this._handleClick(e));
+    }
 
     ready() {
+      super.ready();
       this.$.restAPI.getConfig().then(config => {
         this.config = config;
       });
       this.$.restAPI.getLoggedIn().then(loggedIn => {
         this._loggedIn = loggedIn;
       });
-    },
+    }
 
     _updateExpandedClass(expanded) {
       if (expanded) {
@@ -126,30 +135,30 @@
       } else {
         this.classList.remove('expanded');
       }
-    },
+    }
 
     _computeAuthor(message) {
       return message.author || message.updated_by;
-    },
+    }
 
     _computeShowAvatar(author, config) {
       return !!(author && config && config.plugin && config.plugin.has_avatars);
-    },
+    }
 
     _computeShowOnBehalfOf(message) {
       const author = message.author || message.updated_by;
       return !!(author && message.real_author &&
           author._account_id != message.real_author._account_id);
-    },
+    }
 
     _computeShowReplyButton(message, loggedIn) {
       return message && !!message.message && loggedIn &&
           !this._computeIsAutomated(message);
-    },
+    }
 
     _computeExpanded(expanded) {
       return expanded;
-    },
+    }
 
     /**
      * If there is no value set on the message object as to whether _expanded
@@ -160,33 +169,33 @@
       if (this.message && this.message.expanded === undefined) {
         this.set('message.expanded', Object.keys(value || {}).length > 0);
       }
-    },
+    }
 
     _handleClick(e) {
       if (this.message.expanded) { return; }
       e.stopPropagation();
       this.set('message.expanded', true);
-    },
+    }
 
     _handleAuthorClick(e) {
       if (!this.message.expanded) { return; }
       e.stopPropagation();
       this.set('message.expanded', false);
-    },
+    }
 
     _computeIsAutomated(message) {
       return !!(message.reviewer ||
           this._computeIsReviewerUpdate(message) ||
           (message.tag && message.tag.startsWith('autogenerated')));
-    },
+    }
 
     _computeIsHidden(hideAutomated, isAutomated) {
       return hideAutomated && isAutomated;
-    },
+    }
 
     _computeIsReviewerUpdate(event) {
       return event.type === 'REVIEWER_UPDATE';
-    },
+    }
 
     _getScores(message) {
       if (!message.message) { return []; }
@@ -199,7 +208,7 @@
           .map(s => s.match(LABEL_TITLE_SCORE_PATTERN))
           .filter(ms => ms && ms.length === 3)
           .map(ms => ({label: ms[1], value: ms[2]}));
-    },
+    }
 
     _computeScoreClass(score, labelExtremes) {
       // Polymer 2: check for undefined
@@ -222,14 +231,14 @@
         }
       }
       return classes.join(' ');
-    },
+    }
 
     _computeClass(expanded, showAvatar, message) {
       const classes = [];
       classes.push(expanded ? 'expanded' : 'collapsed');
       classes.push(showAvatar ? 'showAvatar' : 'hideAvatar');
       return classes.join(' ');
-    },
+    }
 
     _handleAnchorClick(e) {
       e.preventDefault();
@@ -238,26 +247,28 @@
         composed: true,
         detail: {id: this.message.id},
       }));
-    },
+    }
 
     _handleReplyTap(e) {
       e.preventDefault();
       this.fire('reply', {message: this.message});
-    },
+    }
 
     _projectNameChanged(name) {
       this.$.restAPI.getProjectConfig(name).then(config => {
         this._projectConfig = config;
       });
-    },
+    }
 
     _computeExpandToggleIcon(expanded) {
       return expanded ? 'gr-icons:expand-less' : 'gr-icons:expand-more';
-    },
+    }
 
     _toggleExpanded(e) {
       e.stopPropagation();
       this.set('message.expanded', !this.message.expanded);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrMessage.is, GrMessage);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-message/gr-message_test.html b/polygerrit-ui/app/elements/change/gr-message/gr-message_test.html
index ef5a756..01bc691 100644
--- a/polygerrit-ui/app/elements/change/gr-message/gr-message_test.html
+++ b/polygerrit-ui/app/elements/change/gr-message/gr-message_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-message</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list.js b/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list.js
index ba4a1a9..92e7cce 100644
--- a/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list.js
+++ b/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list.js
@@ -25,57 +25,61 @@
     SHOW_MORE: 'show-more-messages',
   };
 
-  Polymer({
-    is: 'gr-messages-list',
+  class GrMessagesList extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-messages-list'; }
 
-    properties: {
-      changeNum: Number,
-      messages: {
-        type: Array,
-        value() { return []; },
-      },
-      reviewerUpdates: {
-        type: Array,
-        value() { return []; },
-      },
-      changeComments: Object,
-      projectName: String,
-      showReplyButtons: {
-        type: Boolean,
-        value: false,
-      },
-      labels: Object,
+    static get properties() {
+      return {
+        changeNum: Number,
+        messages: {
+          type: Array,
+          value() { return []; },
+        },
+        reviewerUpdates: {
+          type: Array,
+          value() { return []; },
+        },
+        changeComments: Object,
+        projectName: String,
+        showReplyButtons: {
+          type: Boolean,
+          value: false,
+        },
+        labels: Object,
 
-      _expanded: {
-        type: Boolean,
-        value: false,
-        observer: '_expandedChanged',
-      },
-      _hideAutomated: {
-        type: Boolean,
-        value: false,
-      },
-      /**
+        _expanded: {
+          type: Boolean,
+          value: false,
+          observer: '_expandedChanged',
+        },
+        _hideAutomated: {
+          type: Boolean,
+          value: false,
+        },
+        /**
        * The messages after processing and including merged reviewer updates.
        */
-      _processedMessages: {
-        type: Array,
-        computed: '_computeItems(messages, reviewerUpdates)',
-        observer: '_processedMessagesChanged',
-      },
-      /**
+        _processedMessages: {
+          type: Array,
+          computed: '_computeItems(messages, reviewerUpdates)',
+          observer: '_processedMessagesChanged',
+        },
+        /**
        * The subset of _processedMessages that is visible to the user.
        */
-      _visibleMessages: {
-        type: Array,
-        value() { return []; },
-      },
+        _visibleMessages: {
+          type: Array,
+          value() { return []; },
+        },
 
-      _labelExtremes: {
-        type: Object,
-        computed: '_computeLabelExtremes(labels.*)',
-      },
-    },
+        _labelExtremes: {
+          type: Object,
+          computed: '_computeLabelExtremes(labels.*)',
+        },
+      };
+    }
 
     scrollToMessage(messageID) {
       let el = this.$$('[data-message-id="' + messageID + '"]');
@@ -102,18 +106,18 @@
       el.set('message.expanded', true);
       let top = el.offsetTop;
       for (let offsetParent = el.offsetParent;
-           offsetParent;
-           offsetParent = offsetParent.offsetParent) {
+        offsetParent;
+        offsetParent = offsetParent.offsetParent) {
         top += offsetParent.offsetTop;
       }
       window.scrollTo(0, top);
       this._highlightEl(el);
-    },
+    }
 
     _isAutomated(message) {
       return !!(message.reviewer ||
           (message.tag && message.tag.startsWith('autogenerated')));
-    },
+    }
 
     _computeItems(messages, reviewerUpdates) {
       // Polymer 2: check for undefined
@@ -152,7 +156,7 @@
         }
       }
       return result;
-    },
+    }
 
     _expandedChanged(exp) {
       if (this._processedMessages) {
@@ -169,7 +173,7 @@
           this.notifyPath(`_visibleMessages.${i}.expanded`);
         }
       }
-    },
+    }
 
     _highlightEl(el) {
       const highlightedEls =
@@ -183,23 +187,23 @@
       }
       el.addEventListener('animationend', handleAnimationEnd);
       el.classList.add('highlighted');
-    },
+    }
 
     /**
      * @param {boolean} expand
      */
     handleExpandCollapse(expand) {
       this._expanded = expand;
-    },
+    }
 
     _handleExpandCollapseTap(e) {
       e.preventDefault();
       this.handleExpandCollapse(!this._expanded);
-    },
+    }
 
     _handleAnchorClick(e) {
       this.scrollToMessage(e.detail.id);
-    },
+    }
 
     _hasAutomatedMessages(messages) {
       if (!messages) { return false; }
@@ -209,11 +213,11 @@
         }
       }
       return false;
-    },
+    }
 
     _computeExpandCollapseMessage(expanded) {
       return expanded ? 'Collapse all' : 'Expand all';
-    },
+    }
 
     /**
      * Computes message author's file comments for change's message.
@@ -268,7 +272,7 @@
         }
       }
       return msgComments;
-    },
+    }
 
     /**
      * Returns the number of messages to splice to the beginning of
@@ -293,7 +297,7 @@
         delta = msgsRemaining - i;
       }
       return Math.min(msgsRemaining, delta);
-    },
+    }
 
     /**
      * Gets the number of messages that would be visible, but do not currently
@@ -309,20 +313,20 @@
             this._getHumanMessages(visibleMessages).length;
       }
       return messages.length - visibleMessages.length;
-    },
+    }
 
     _computeIncrementText(visibleMessages, messages, hideAutomated) {
       let delta = this._getDelta(visibleMessages, messages, hideAutomated);
       delta = Math.min(
           this._numRemaining(visibleMessages, messages, hideAutomated), delta);
       return 'Show ' + Math.min(MESSAGES_INCREMENT, delta) + ' more';
-    },
+    }
 
     _getHumanMessages(messages) {
       return messages.filter(msg => {
         return !this._isAutomated(msg);
       });
-    },
+    }
 
     _computeShowHideTextHidden(visibleMessages, messages,
         hideAutomated) {
@@ -335,12 +339,12 @@
         visibleMessages = this._getHumanMessages(visibleMessages);
       }
       return visibleMessages.length >= messages.length;
-    },
+    }
 
     _handleShowAllTap() {
       this._visibleMessages = this._processedMessages;
       this.$.reporting.reportInteraction(ReportingEvent.SHOW_ALL);
-    },
+    }
 
     _handleIncrementShownMessages() {
       const delta = this._getDelta(this._visibleMessages,
@@ -350,27 +354,27 @@
       // Add newMessages to the beginning of _visibleMessages
       this.splice(...['_visibleMessages', 0, 0].concat(newMessages));
       this.$.reporting.reportInteraction(ReportingEvent.SHOW_MORE);
-    },
+    }
 
     _processedMessagesChanged(messages) {
       if (messages) {
         this._visibleMessages = messages.slice(-MAX_INITIAL_SHOWN_MESSAGES);
       }
-    },
+    }
 
     _computeNumMessagesText(visibleMessages, messages,
         hideAutomated) {
       const total =
           this._numRemaining(visibleMessages, messages, hideAutomated);
       return total === 1 ? 'Show 1 message' : 'Show all ' + total + ' messages';
-    },
+    }
 
     _computeIncrementHidden(visibleMessages, messages,
         hideAutomated) {
       const total =
           this._numRemaining(visibleMessages, messages, hideAutomated);
       return total <= this._getDelta(visibleMessages, messages, hideAutomated);
-    },
+    }
 
     /**
      * Compute a mapping from label name to objects representing the minimum and
@@ -389,6 +393,8 @@
         extremes[key] = {min: values[0], max: values[values.length - 1]};
       }
       return extremes;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrMessagesList.is, GrMessagesList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list_test.html b/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list_test.html
index 315403e..9caf13d 100644
--- a/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-messages-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -49,7 +49,6 @@
 </test-fixture>
 
 <script>
-
   const randomMessage = function(opt_params) {
     const params = opt_params || {};
     const author1 = {
@@ -517,7 +516,6 @@
       assert.equal(element._getDelta([], messages, false), 1);
       assert.equal(element._getDelta([], messages, true), 1);
 
-
       messages = _.times(7, randomMessage);
       assert.equal(element._getDelta([], messages, false), 5);
       assert.equal(element._getDelta([], messages, true), 5);
diff --git a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list.js b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list.js
index 76c5980..25a56a9 100644
--- a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list.js
+++ b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list.js
@@ -17,9 +17,19 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-related-changes-list',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrRelatedChangesList extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-related-changes-list'; }
     /**
      * Fired when a new section is loaded so that the change view can determine
      * a show more button is needed, sometimes before all the sections finish
@@ -28,64 +38,62 @@
      * @event new-section-loaded
      */
 
-    properties: {
-      change: Object,
-      hasParent: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
-      patchNum: String,
-      parentChange: Object,
-      hidden: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      loading: {
-        type: Boolean,
-        notify: true,
-      },
-      mergeable: Boolean,
-      _connectedRevisions: {
-        type: Array,
-        computed: '_computeConnectedRevisions(change, patchNum, ' +
+    static get properties() {
+      return {
+        change: Object,
+        hasParent: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
+        patchNum: String,
+        parentChange: Object,
+        hidden: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        loading: {
+          type: Boolean,
+          notify: true,
+        },
+        mergeable: Boolean,
+        _connectedRevisions: {
+          type: Array,
+          computed: '_computeConnectedRevisions(change, patchNum, ' +
             '_relatedResponse.changes)',
-      },
-      /** @type {?} */
-      _relatedResponse: {
-        type: Object,
-        value() { return {changes: []}; },
-      },
-      /** @type {?} */
-      _submittedTogether: {
-        type: Object,
-        value() { return {changes: []}; },
-      },
-      _conflicts: {
-        type: Array,
-        value() { return []; },
-      },
-      _cherryPicks: {
-        type: Array,
-        value() { return []; },
-      },
-      _sameTopic: {
-        type: Array,
-        value() { return []; },
-      },
-    },
+        },
+        /** @type {?} */
+        _relatedResponse: {
+          type: Object,
+          value() { return {changes: []}; },
+        },
+        /** @type {?} */
+        _submittedTogether: {
+          type: Object,
+          value() { return {changes: []}; },
+        },
+        _conflicts: {
+          type: Array,
+          value() { return []; },
+        },
+        _cherryPicks: {
+          type: Array,
+          value() { return []; },
+        },
+        _sameTopic: {
+          type: Array,
+          value() { return []; },
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
-
-    observers: [
-      '_resultsChanged(_relatedResponse, _submittedTogether, ' +
+    static get observers() {
+      return [
+        '_resultsChanged(_relatedResponse, _submittedTogether, ' +
           '_conflicts, _cherryPicks, _sameTopic)',
-    ],
+      ];
+    }
 
     clear() {
       this.loading = true;
@@ -96,7 +104,7 @@
       this._conflicts = [];
       this._cherryPicks = [];
       this._sameTopic = [];
-    },
+    }
 
     reload() {
       if (!this.change || !this.patchNum) {
@@ -144,7 +152,7 @@
       return Promise.all(promises).then(() => {
         this.loading = false;
       });
-    },
+    }
 
     _fireReloadEvent() {
       // The listener on the change computes height of the related changes
@@ -152,7 +160,7 @@
       // that requires a flush.
       Polymer.dom.flush();
       this.dispatchEvent(new CustomEvent('new-section-loaded'));
-    },
+    }
 
     /**
      * Determines whether or not the given change has a parent change. If there
@@ -166,34 +174,34 @@
       return relatedChanges.length > 0 &&
           relatedChanges[relatedChanges.length - 1].change_id !==
           currentChangeId;
-    },
+    }
 
     _getRelatedChanges() {
       return this.$.restAPI.getRelatedChanges(this.change._number,
           this.patchNum);
-    },
+    }
 
     _getSubmittedTogether() {
       return this.$.restAPI.getChangesSubmittedTogether(this.change._number);
-    },
+    }
 
     _getServerConfig() {
       return this.$.restAPI.getConfig();
-    },
+    }
 
     _getConflicts() {
       return this.$.restAPI.getChangeConflicts(this.change._number);
-    },
+    }
 
     _getCherryPicks() {
       return this.$.restAPI.getChangeCherryPicks(this.change.project,
           this.change.change_id, this.change._number);
-    },
+    }
 
     _getChangesWithSameTopic() {
       return this.$.restAPI.getChangesWithSameTopic(this.change.topic,
           this.change._number);
-    },
+    }
 
     /**
      * @param {number} changeNum
@@ -203,7 +211,7 @@
      */
     _computeChangeURL(changeNum, project, opt_patchNum) {
       return Gerrit.Nav.getUrlForChangeById(changeNum, project, opt_patchNum);
-    },
+    }
 
     _computeChangeContainerClass(currentChange, relatedChange) {
       const classes = ['changeContainer'];
@@ -214,7 +222,7 @@
         classes.push('thisChange');
       }
       return classes.join(' ');
-    },
+    }
 
     /**
      * Do the given objects describe the same change? Compares the changes by
@@ -229,7 +237,7 @@
       const aNum = this._getChangeNumber(a);
       const bNum = this._getChangeNumber(b);
       return aNum === bNum;
-    },
+    }
 
     /**
      * Get the change number from either a ChangeInfo (such as those included in
@@ -251,7 +259,7 @@
         return change._change_number;
       }
       return change._number;
-    },
+    }
 
     _computeLinkClass(change) {
       const statuses = [];
@@ -262,7 +270,7 @@
         statuses.push('submittable');
       }
       return statuses.join(' ');
-    },
+    }
 
     _computeChangeStatusClass(change) {
       const classes = ['status'];
@@ -276,7 +284,7 @@
         classes.push('hidden');
       }
       return classes.join(' ');
-    },
+    }
 
     _computeChangeStatus(change) {
       switch (change.status) {
@@ -293,7 +301,7 @@
         return 'Submittable';
       }
       return '';
-    },
+    }
 
     _resultsChanged(related, submittedTogether, conflicts,
         cherryPicks, sameTopic) {
@@ -323,11 +331,11 @@
         }
       }
       this.hidden = true;
-    },
+    }
 
     _isIndirectAncestor(change) {
       return !this._connectedRevisions.includes(change.commit.commit);
-    },
+    }
 
     _computeConnectedRevisions(change, patchNum, relatedChanges) {
       // Polymer 2: check for undefined
@@ -364,20 +372,22 @@
         --pos;
       }
       return connected;
-    },
+    }
 
     _computeSubmittedTogetherClass(submittedTogether) {
       if (!submittedTogether || (
-          submittedTogether.changes.length === 0 &&
+        submittedTogether.changes.length === 0 &&
           !submittedTogether.non_visible_changes)) {
         return 'hidden';
       }
       return '';
-    },
+    }
 
     _computeNonVisibleChangesNote(n) {
       const noun = n === 1 ? 'change' : 'changes';
       return `(+ ${n} non-visible ${noun})`;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRelatedChangesList.is, GrRelatedChangesList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_test.html b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_test.html
index 06b7a5d..38b2fb9 100644
--- a/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-related-changes-list/gr-related-changes-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-related-changes-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -321,7 +321,7 @@
         sandbox.stub(element, '_getCherryPicks')
             .returns(Promise.resolve());
         conflictsStub = sandbox.stub(element, '_getConflicts')
-          .returns(Promise.resolve());
+            .returns(Promise.resolve());
       });
 
       test('request conflicts if open and mergeable', () => {
diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog-it_test.html b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog-it_test.html
index 3632348..7d95323 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog-it_test.html
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog-it_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reply-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -156,7 +156,7 @@
             const labelScoreRows = Polymer.dom(element.$.labelScores.root)
                 .querySelector('gr-label-score-row[name="Code-Review"]');
             const selectedBtn = Polymer.dom(labelScoreRows.root)
-                .querySelector('gr-button[value="+1"].iron-selected');
+                .querySelector('gr-button[data-value="+1"].iron-selected');
             assert.isOk(selectedBtn);
             done();
           });
diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.js b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.js
index cc7fbe6..eab1c8d 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog.js
@@ -52,9 +52,23 @@
 
   const SEND_REPLY_TIMING_LABEL = 'SendReply';
 
-  Polymer({
-    is: 'gr-reply-dialog',
-
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrReplyDialog extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-reply-dialog'; }
     /**
      * Fired when a reply is successfully sent.
      *
@@ -87,169 +101,172 @@
      * @event comment-refresh
      */
 
-     /**
+    /**
       * Fires when the state of the send button (enabled/disabled) changes.
       *
       * @event send-disabled-changed
       */
 
-    properties: {
+    constructor() {
+      super();
+      this.FocusTarget = FocusTarget;
+    }
+
+    static get properties() {
+      return {
       /**
        * @type {{ _number: number, removable_reviewers: Array }}
        */
-      change: Object,
-      patchNum: String,
-      canBeStarted: {
-        type: Boolean,
-        value: false,
-      },
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      draft: {
-        type: String,
-        value: '',
-        observer: '_draftChanged',
-      },
-      quote: {
-        type: String,
-        value: '',
-      },
-      diffDrafts: {
-        type: Object,
-        observer: '_handleHeightChanged',
-      },
-      /** @type {!Function} */
-      filterReviewerSuggestion: {
-        type: Function,
-        value() {
-          return this._filterReviewerSuggestionGenerator(false);
+        change: Object,
+        patchNum: String,
+        canBeStarted: {
+          type: Boolean,
+          value: false,
         },
-      },
-      /** @type {!Function} */
-      filterCCSuggestion: {
-        type: Function,
-        value() {
-          return this._filterReviewerSuggestionGenerator(true);
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
         },
-      },
-      permittedLabels: Object,
-      /**
+        draft: {
+          type: String,
+          value: '',
+          observer: '_draftChanged',
+        },
+        quote: {
+          type: String,
+          value: '',
+        },
+        diffDrafts: {
+          type: Object,
+          observer: '_handleHeightChanged',
+        },
+        /** @type {!Function} */
+        filterReviewerSuggestion: {
+          type: Function,
+          value() {
+            return this._filterReviewerSuggestionGenerator(false);
+          },
+        },
+        /** @type {!Function} */
+        filterCCSuggestion: {
+          type: Function,
+          value() {
+            return this._filterReviewerSuggestionGenerator(true);
+          },
+        },
+        permittedLabels: Object,
+        /**
        * @type {{ commentlinks: Array }}
        */
-      projectConfig: Object,
-      knownLatestState: String,
-      underReview: {
-        type: Boolean,
-        value: true,
-      },
-
-      _account: Object,
-      _ccs: Array,
-      /** @type {?Object} */
-      _ccPendingConfirmation: {
-        type: Object,
-        observer: '_reviewerPendingConfirmationUpdated',
-      },
-      _messagePlaceholder: {
-        type: String,
-        computed: '_computeMessagePlaceholder(canBeStarted)',
-      },
-      _owner: Object,
-      /** @type {?} */
-      _pendingConfirmationDetails: Object,
-      _includeComments: {
-        type: Boolean,
-        value: true,
-      },
-      _reviewers: Array,
-      /** @type {?Object} */
-      _reviewerPendingConfirmation: {
-        type: Object,
-        observer: '_reviewerPendingConfirmationUpdated',
-      },
-      _previewFormatting: {
-        type: Boolean,
-        value: false,
-        observer: '_handleHeightChanged',
-      },
-      _reviewersPendingRemove: {
-        type: Object,
-        value: {
-          CC: [],
-          REVIEWER: [],
+        projectConfig: Object,
+        knownLatestState: String,
+        underReview: {
+          type: Boolean,
+          value: true,
         },
-      },
-      _sendButtonLabel: {
-        type: String,
-        computed: '_computeSendButtonLabel(canBeStarted)',
-      },
-      _savingComments: Boolean,
-      _reviewersMutated: {
-        type: Boolean,
-        value: false,
-      },
-      _labelsChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _saveTooltip: {
-        type: String,
-        value: ButtonTooltips.SAVE,
-        readOnly: true,
-      },
-      _pluginMessage: {
-        type: String,
-        value: '',
-      },
-      _sendDisabled: {
-        type: Boolean,
-        computed: '_computeSendButtonDisabled(_sendButtonLabel, diffDrafts, ' +
-            'draft, _reviewersMutated, _labelsChanged, _includeComments, ' +
-            'disabled)',
-        observer: '_sendDisabledChanged',
-      },
-    },
 
-    FocusTarget,
+        _account: Object,
+        _ccs: Array,
+        /** @type {?Object} */
+        _ccPendingConfirmation: {
+          type: Object,
+          observer: '_reviewerPendingConfirmationUpdated',
+        },
+        _messagePlaceholder: {
+          type: String,
+          computed: '_computeMessagePlaceholder(canBeStarted)',
+        },
+        _owner: Object,
+        /** @type {?} */
+        _pendingConfirmationDetails: Object,
+        _includeComments: {
+          type: Boolean,
+          value: true,
+        },
+        _reviewers: Array,
+        /** @type {?Object} */
+        _reviewerPendingConfirmation: {
+          type: Object,
+          observer: '_reviewerPendingConfirmationUpdated',
+        },
+        _previewFormatting: {
+          type: Boolean,
+          value: false,
+          observer: '_handleHeightChanged',
+        },
+        _reviewersPendingRemove: {
+          type: Object,
+          value: {
+            CC: [],
+            REVIEWER: [],
+          },
+        },
+        _sendButtonLabel: {
+          type: String,
+          computed: '_computeSendButtonLabel(canBeStarted)',
+        },
+        _savingComments: Boolean,
+        _reviewersMutated: {
+          type: Boolean,
+          value: false,
+        },
+        _labelsChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _saveTooltip: {
+          type: String,
+          value: ButtonTooltips.SAVE,
+          readOnly: true,
+        },
+        _pluginMessage: {
+          type: String,
+          value: '',
+        },
+        _sendDisabled: {
+          type: Boolean,
+          computed: '_computeSendButtonDisabled(_sendButtonLabel, ' +
+            'diffDrafts, draft, _reviewersMutated, _labelsChanged, ' +
+            '_includeComments, disabled)',
+          observer: '_sendDisabledChanged',
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
+    get keyBindings() {
+      return {
+        'esc': '_handleEscKey',
+        'ctrl+enter meta+enter': '_handleEnterKey',
+      };
+    }
 
-    keyBindings: {
-      'esc': '_handleEscKey',
-      'ctrl+enter meta+enter': '_handleEnterKey',
-    },
-
-    observers: [
-      '_changeUpdated(change.reviewers.*, change.owner)',
-      '_ccsChanged(_ccs.splices)',
-      '_reviewersChanged(_reviewers.splices)',
-    ],
+    static get observers() {
+      return [
+        '_changeUpdated(change.reviewers.*, change.owner)',
+        '_ccsChanged(_ccs.splices)',
+        '_reviewersChanged(_reviewers.splices)',
+      ];
+    }
 
     attached() {
+      super.attached();
       this._getAccount().then(account => {
         this._account = account || {};
       });
-    },
+    }
 
     ready() {
+      super.ready();
       this.$.jsAPI.addElement(this.$.jsAPI.Element.REPLY_DIALOG, this);
-    },
+    }
 
     open(opt_focusTarget) {
       this.knownLatestState = LatestPatchState.CHECKING;
       this.fetchChangeUpdates(this.change, this.$.restAPI)
           .then(result => {
             this.knownLatestState = result.isLatest ?
-                LatestPatchState.LATEST : LatestPatchState.NOT_LATEST;
+              LatestPatchState.LATEST : LatestPatchState.NOT_LATEST;
           });
 
       this._focusOn(opt_focusTarget);
@@ -268,11 +285,11 @@
           this._savingComments = false;
         });
       }
-    },
+    }
 
     focus() {
       this._focusOn(FocusTarget.ANY);
-    },
+    }
 
     getFocusStops() {
       const end = this._sendDisabled ? this.$.cancelButton : this.$.sendButton;
@@ -280,14 +297,14 @@
         start: this.$.reviewers.focusStart,
         end,
       };
-    },
+    }
 
     setLabelValue(label, value) {
       const selectorEl =
           this.$.labelScores.$$(`gr-label-score-row[name="${label}"]`);
       if (!selectorEl) { return; }
       selectorEl.setSelectedValue(value);
-    },
+    }
 
     getLabelValue(label) {
       const selectorEl =
@@ -295,23 +312,23 @@
       if (!selectorEl) { return null; }
 
       return selectorEl.selectedValue;
-    },
+    }
 
     _handleEscKey(e) {
       this.cancel();
-    },
+    }
 
     _handleEnterKey(e) {
       this._submit();
-    },
+    }
 
     _ccsChanged(splices) {
       this._reviewerTypeChanged(splices, ReviewerTypes.CC);
-    },
+    }
 
     _reviewersChanged(splices) {
       this._reviewerTypeChanged(splices, ReviewerTypes.REVIEWER);
-    },
+    }
 
     _reviewerTypeChanged(splices, reviewerType) {
       if (splices && splices.indexSplices) {
@@ -342,7 +359,7 @@
           }
         }
       }
-    },
+    }
 
     _processReviewerChange(indexSplices, type) {
       for (const splice of indexSplices) {
@@ -354,7 +371,7 @@
           this._reviewersPendingRemove[type].push(account);
         }
       }
-    },
+    }
 
     /**
      * Resets the state of the _reviewersPendingRemove object, and removes
@@ -380,7 +397,7 @@
           this._reviewersPendingRemove[type] = [];
         }
       }
-    },
+    }
 
     /**
      * Removes an account from the change, both on the backend and the client.
@@ -394,17 +411,17 @@
 
       return this.$.restAPI.removeChangeReviewer(this.change._number,
           account._account_id).then(response => {
-            if (!response.ok) { return response; }
+        if (!response.ok) { return response; }
 
-            const reviewers = this.change.reviewers[type] || [];
-            for (let i = 0; i < reviewers.length; i++) {
-              if (reviewers[i]._account_id == account._account_id) {
-                this.splice(`change.reviewers.${type}`, i, 1);
-                break;
-              }
-            }
-          });
-    },
+        const reviewers = this.change.reviewers[type] || [];
+        for (let i = 0; i < reviewers.length; i++) {
+          if (reviewers[i]._account_id == account._account_id) {
+            this.splice(`change.reviewers.${type}`, i, 1);
+            break;
+          }
+        }
+      });
+    }
 
     _mapReviewer(reviewer) {
       let reviewerId;
@@ -416,7 +433,7 @@
         confirmed = reviewer.group.confirmed;
       }
       return {reviewer: reviewerId, confirmed};
-    },
+    }
 
     send(includeComments, startReview) {
       this.$.reporting.time(SEND_REPLY_TIMING_LABEL);
@@ -479,7 +496,7 @@
         this.disabled = false;
         throw err;
       });
-    },
+    }
 
     _focusOn(section) {
       // Safeguard- always want to focus on something.
@@ -497,7 +514,7 @@
         const ccEntry = this.$.ccs.focusStart;
         ccEntry.async(ccEntry.focus);
       }
-    },
+    }
 
     _chooseFocusTarget() {
       // If we are the owner and the reviewers field is empty, focus on that.
@@ -509,7 +526,7 @@
 
       // Default to BODY.
       return FocusTarget.BODY;
-    },
+    }
 
     _handle400Error(response) {
       // A call to _saveReview could fail with a server error if erroneous
@@ -551,11 +568,11 @@
         this.fire('server-error', {response});
         return null; // Means that the error has been handled.
       });
-    },
+    }
 
     _computeHideDraftList(drafts) {
       return Object.keys(drafts || {}).length == 0;
-    },
+    }
 
     _computeDraftsTitle(drafts) {
       let total = 0;
@@ -567,13 +584,13 @@
       if (total == 0) { return ''; }
       if (total == 1) { return '1 Draft'; }
       if (total > 1) { return total + ' Drafts'; }
-    },
+    }
 
     _computeMessagePlaceholder(canBeStarted) {
       return canBeStarted ?
         'Add a note for your reviewers...' :
         'Say something nice...';
-    },
+    }
 
     _changeUpdated(changeRecord, owner) {
       // Polymer 2: check for undefined
@@ -582,7 +599,7 @@
       }
 
       this._rebuildReviewerArrays(changeRecord.base, owner);
-    },
+    }
 
     _rebuildReviewerArrays(change, owner) {
       this._owner = owner;
@@ -614,11 +631,11 @@
 
       this._ccs = ccs;
       this._reviewers = reviewers;
-    },
+    }
 
     _accountOrGroupKey(entry) {
       return entry.id || entry._account_id;
-    },
+    }
 
     /**
      * Generates a function to filter out reviewer/CC entries. When isCCs is
@@ -650,23 +667,23 @@
         }
         return this._reviewers.find(finder) === undefined;
       };
-    },
+    }
 
     _getAccount() {
       return this.$.restAPI.getAccount();
-    },
+    }
 
     _cancelTapHandler(e) {
       e.preventDefault();
       this.cancel();
-    },
+    }
 
     cancel() {
       this.fire('cancel', null, {bubbles: false});
       this.$.textarea.closeDropdown();
       this._purgeReviewersPendingRemove(true);
       this._rebuildReviewerArrays(this.change.reviewers, this._owner);
-    },
+    }
 
     _saveTapHandler(e) {
       e.preventDefault();
@@ -678,12 +695,12 @@
       this.send(this._includeComments, false).then(keepReviewers => {
         this._purgeReviewersPendingRemove(false, keepReviewers);
       });
-    },
+    }
 
     _sendTapHandler(e) {
       e.preventDefault();
       this._submit();
-    },
+    }
 
     _submit() {
       if (!this.$.ccs.submitEntryText()) {
@@ -710,12 +727,12 @@
               detail: {message: `Error submitting review ${err}`},
             }));
           });
-    },
+    }
 
     _saveReview(review, opt_errFn) {
       return this.$.restAPI.saveChangeReview(this.change._number, this.patchNum,
           review, opt_errFn);
-    },
+    }
 
     _reviewerPendingConfirmationUpdated(reviewer) {
       if (reviewer === null) {
@@ -725,7 +742,7 @@
             this._ccPendingConfirmation || this._reviewerPendingConfirmation;
         this.$.reviewerConfirmationOverlay.open();
       }
-    },
+    }
 
     _confirmPendingReviewer() {
       if (this._ccPendingConfirmation) {
@@ -735,7 +752,7 @@
         this.$.reviewers.confirmGroup(this._reviewerPendingConfirmation.group);
         this._focusOn(FocusTarget.REVIEWERS);
       }
-    },
+    }
 
     _cancelPendingReviewer() {
       this._ccPendingConfirmation = null;
@@ -744,7 +761,7 @@
       const target =
           this._ccPendingConfirmation ? FocusTarget.CCS : FocusTarget.REVIEWERS;
       this._focusOn(target);
-    },
+    }
 
     _getStorageLocation() {
       // Tests trigger this method without setting change.
@@ -754,12 +771,12 @@
         patchNum: '@change',
         path: '@change',
       };
-    },
+    }
 
     _loadStoredDraft() {
       const draft = this.$.storage.getDraftComment(this._getStorageLocation());
       return draft ? draft.message : '';
-    },
+    }
 
     _handleAccountTextEntry() {
       // When either of the account entries has input added to the autocomplete,
@@ -767,7 +784,7 @@
       //
       // Note: if the text is removed, the save button will not get disabled.
       this._reviewersMutated = true;
-    },
+    }
 
     _draftChanged(newDraft, oldDraft) {
       this.debounce('store', () => {
@@ -780,37 +797,37 @@
               this.draft);
         }
       }, STORAGE_DEBOUNCE_INTERVAL_MS);
-    },
+    }
 
     _handleHeightChanged(e) {
       this.fire('autogrow');
-    },
+    }
 
     _handleLabelsChanged() {
       this._labelsChanged = Object.keys(
           this.$.labelScores.getLabelValues()).length !== 0;
-    },
+    }
 
     _isState(knownLatestState, value) {
       return knownLatestState === value;
-    },
+    }
 
     _reload() {
       // Load the current change without any patch range.
       location.href = this.getBaseUrl() + '/c/' + this.change._number;
-    },
+    }
 
     _computeSendButtonLabel(canBeStarted) {
       return canBeStarted ? ButtonLabels.START_REVIEW : ButtonLabels.SEND;
-    },
+    }
 
     _computeSendButtonTooltip(canBeStarted) {
       return canBeStarted ? ButtonTooltips.START_REVIEW : ButtonTooltips.SEND;
-    },
+    }
 
     _computeSavingLabelClass(savingComments) {
       return savingComments ? 'saving' : '';
-    },
+    }
 
     _computeSendButtonDisabled(buttonLabel, drafts, text, reviewersMutated,
         labelsChanged, includeComments, disabled) {
@@ -831,7 +848,7 @@
       if (buttonLabel === ButtonLabels.START_REVIEW) { return false; }
       const hasDrafts = includeComments && Object.keys(drafts).length;
       return !hasDrafts && !text.length && !reviewersMutated && !labelsChanged;
-    },
+    }
 
     _computePatchSetWarning(patchNum, labelsChanged) {
       let str = `Patch ${patchNum} is not latest.`;
@@ -839,28 +856,30 @@
         str += ' Voting on a non-latest patch will have no effect.';
       }
       return str;
-    },
+    }
 
     setPluginMessage(message) {
       this._pluginMessage = message;
-    },
+    }
 
     _sendDisabledChanged(sendDisabled) {
       this.dispatchEvent(new CustomEvent('send-disabled-changed'));
-    },
+    }
 
     _getReviewerSuggestionsProvider(change) {
       const provider = GrReviewerSuggestionsProvider.create(this.$.restAPI,
           change._number, Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.REVIEWER);
       provider.init();
       return provider;
-    },
+    }
 
     _getCcSuggestionsProvider(change) {
       const provider = GrReviewerSuggestionsProvider.create(this.$.restAPI,
           change._number, Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.CC);
       provider.init();
       return provider;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrReplyDialog.is, GrReplyDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_test.html b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_test.html
index 727373a..badd62a 100644
--- a/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-reply-dialog/gr-reply-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reply-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -414,8 +414,8 @@
       }).then(() => {
         assert.isFalse(isVisible(element.$.reviewerConfirmationOverlay));
         const additions = cc ?
-            element.$.ccs.additions() :
-            element.$.reviewers.additions();
+          element.$.ccs.additions() :
+          element.$.reviewers.additions();
         assert.deepEqual(
             additions,
             [
@@ -843,7 +843,7 @@
       // Send and purge and verify moves, delete cc3.
       element.send()
           .then(keepReviewers =>
-              element._purgeReviewersPendingRemove(false, keepReviewers))
+            element._purgeReviewersPendingRemove(false, keepReviewers))
           .then(() => {
             assert.deepEqual(
                 mutations, [
@@ -1084,7 +1084,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ false,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       assert.isTrue(fn(
           /* buttonLabel= */ 'Send',
@@ -1093,7 +1093,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ false,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Mock nonempty comment draft array, with seding comments.
       assert.isFalse(fn(
@@ -1103,7 +1103,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ false,
           /* includeComments= */ true,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Mock nonempty comment draft array, without seding comments.
       assert.isTrue(fn(
@@ -1113,7 +1113,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ false,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Mock nonempty change message.
       assert.isFalse(fn(
@@ -1123,7 +1123,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ false,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Mock reviewers mutated.
       assert.isFalse(fn(
@@ -1133,7 +1133,7 @@
           /* reviewersMutated= */ true,
           /* labelsChanged= */ false,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Mock labels changed.
       assert.isFalse(fn(
@@ -1143,7 +1143,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ true,
           /* includeComments= */ false,
-          /* disabled= */ false,
+          /* disabled= */ false
       ));
       // Whole dialog is disabled.
       assert.isTrue(fn(
@@ -1153,7 +1153,7 @@
           /* reviewersMutated= */ false,
           /* labelsChanged= */ true,
           /* includeComments= */ false,
-          /* disabled= */ true,
+          /* disabled= */ true
       ));
     });
 
diff --git a/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list.js b/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list.js
index d8df9d4..3cc79fa 100644
--- a/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list.js
+++ b/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list.js
@@ -17,70 +17,75 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-reviewer-list',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrReviewerList extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-reviewer-list'; }
     /**
      * Fired when the "Add reviewer..." button is tapped.
      *
      * @event show-reply-dialog
      */
 
-    properties: {
-      change: Object,
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      mutable: {
-        type: Boolean,
-        value: false,
-      },
-      reviewersOnly: {
-        type: Boolean,
-        value: false,
-      },
-      ccsOnly: {
-        type: Boolean,
-        value: false,
-      },
-      maxReviewersDisplayed: Number,
+    static get properties() {
+      return {
+        change: Object,
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        mutable: {
+          type: Boolean,
+          value: false,
+        },
+        reviewersOnly: {
+          type: Boolean,
+          value: false,
+        },
+        ccsOnly: {
+          type: Boolean,
+          value: false,
+        },
+        maxReviewersDisplayed: Number,
 
-      _displayedReviewers: {
-        type: Array,
-        value() { return []; },
-      },
-      _reviewers: {
-        type: Array,
-        value() { return []; },
-      },
-      _showInput: {
-        type: Boolean,
-        value: false,
-      },
-      _addLabel: {
-        type: String,
-        computed: '_computeAddLabel(ccsOnly)',
-      },
-      _hiddenReviewerCount: {
-        type: Number,
-        computed: '_computeHiddenCount(_reviewers, _displayedReviewers)',
-      },
+        _displayedReviewers: {
+          type: Array,
+          value() { return []; },
+        },
+        _reviewers: {
+          type: Array,
+          value() { return []; },
+        },
+        _showInput: {
+          type: Boolean,
+          value: false,
+        },
+        _addLabel: {
+          type: String,
+          computed: '_computeAddLabel(ccsOnly)',
+        },
+        _hiddenReviewerCount: {
+          type: Number,
+          computed: '_computeHiddenCount(_reviewers, _displayedReviewers)',
+        },
 
+        // Used for testing.
+        _lastAutocompleteRequest: Object,
+        _xhrPromise: Object,
+      };
+    }
 
-      // Used for testing.
-      _lastAutocompleteRequest: Object,
-      _xhrPromise: Object,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_reviewersChanged(change.reviewers.*, change.owner)',
-    ],
+    static get observers() {
+      return [
+        '_reviewersChanged(change.reviewers.*, change.owner)',
+      ];
+    }
 
     /**
      * Converts change.permitted_labels to an array of hashes of label keys to
@@ -101,7 +106,7 @@
         label,
         scores: labels[label].map(v => parseInt(v, 10)),
       }));
-    },
+    }
 
     /**
      * Returns hash of labels to max permitted score.
@@ -115,7 +120,7 @@
                 .map(v => parseInt(v, 10))
                 .reduce((a, b) => Math.max(a, b))}))
           .reduce((acc, i) => Object.assign(acc, i), {});
-    },
+    }
 
     /**
      * Returns max permitted score for reviewer.
@@ -140,7 +145,7 @@
         return 0;
       }
       return NaN;
-    },
+    }
 
     _computeReviewerTooltip(reviewer, change) {
       if (!change || !change.labels) { return ''; }
@@ -161,7 +166,7 @@
       } else {
         return '';
       }
-    },
+    }
 
     _reviewersChanged(changeRecord, owner) {
       // Polymer 2: check for undefined
@@ -195,7 +200,7 @@
       } else {
         this._displayedReviewers = this._reviewers;
       }
-    },
+    }
 
     _computeHiddenCount(reviewers, displayedReviewers) {
       // Polymer 2: check for undefined
@@ -204,7 +209,7 @@
       }
 
       return reviewers.length - displayedReviewers.length;
-    },
+    }
 
     _computeCanRemoveReviewer(reviewer, mutable) {
       if (!mutable) { return false; }
@@ -218,7 +223,7 @@
         }
       }
       return false;
-    },
+    }
 
     _handleRemove(e) {
       e.preventDefault();
@@ -246,7 +251,7 @@
         this.disabled = false;
         throw err;
       });
-    },
+    }
 
     _handleAddTap(e) {
       e.preventDefault();
@@ -258,18 +263,20 @@
         value.ccsOnly = true;
       }
       this.fire('show-reply-dialog', {value});
-    },
+    }
 
     _handleViewAll(e) {
       this._displayedReviewers = this._reviewers;
-    },
+    }
 
     _removeReviewer(id) {
       return this.$.restAPI.removeChangeReviewer(this.change._number, id);
-    },
+    }
 
     _computeAddLabel(ccsOnly) {
       return ccsOnly ? 'Add CC' : 'Add reviewer';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrReviewerList.is, GrReviewerList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list_test.html b/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list_test.html
index ae4934c..18f7bc5 100644
--- a/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-reviewer-list/gr-reviewer-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reviewer-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -196,7 +196,7 @@
       element.maxReviewersDisplayed = 5;
       for (let i = 0; i < 6; i++) {
         reviewers.push(
-          {email: i+'reviewer@google.com', name: 'reviewer-' + i});
+            {email: i+'reviewer@google.com', name: 'reviewer-' + i});
       }
       element.ccsOnly = true;
 
@@ -219,7 +219,7 @@
       element.maxReviewersDisplayed = 5;
       for (let i = 0; i < 8; i++) {
         reviewers.push(
-          {email: i+'reviewer@google.com', name: 'reviewer-' + i});
+            {email: i+'reviewer@google.com', name: 'reviewer-' + i});
       }
       element.ccsOnly = true;
 
@@ -237,12 +237,11 @@
       assert.isFalse(element.$$('.hiddenReviewers').hidden);
     });
 
-
     test('no maxReviewersDisplayed', () => {
       const reviewers = [];
       for (let i = 0; i < 7; i++) {
         reviewers.push(
-          {email: i+'reviewer@google.com', name: 'reviewer-' + i});
+            {email: i+'reviewer@google.com', name: 'reviewer-' + i});
       }
       element.ccsOnly = true;
 
@@ -265,7 +264,7 @@
       element.maxReviewersDisplayed = 5;
       for (let i = 0; i < 100; i++) {
         reviewers.push(
-          {email: i+'reviewer@google.com', name: 'reviewer-' + i});
+            {email: i+'reviewer@google.com', name: 'reviewer-' + i});
       }
       element.ccsOnly = true;
 
@@ -298,7 +297,7 @@
           },
           Bar: {
             all: [{_account_id: 1, permitted_voting_range: {max: 1}},
-                  {_account_id: 7, permitted_voting_range: {max: 1}}],
+              {_account_id: 7, permitted_voting_range: {max: 1}}],
           },
           FooBar: {
             all: [{_account_id: 7, value: 0}],
diff --git a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.js b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.js
index be2f0ea..3a6b2df 100644
--- a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.js
+++ b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list.js
@@ -22,39 +22,42 @@
    *
    * @event thread-list-modified
    */
+  class GrThreadList extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-thread-list'; }
 
-  Polymer({
-    is: 'gr-thread-list',
-
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      change: Object,
-      threads: Array,
-      changeNum: String,
-      loggedIn: Boolean,
-      _sortedThreads: {
-        type: Array,
-      },
-      _filteredThreads: {
-        type: Array,
-        computed: '_computeFilteredThreads(_sortedThreads, _unresolvedOnly, ' +
-            '_draftsOnly)',
-      },
-      _unresolvedOnly: {
-        type: Boolean,
-        value: false,
-      },
-      _draftsOnly: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        change: Object,
+        threads: Array,
+        changeNum: String,
+        loggedIn: Boolean,
+        _sortedThreads: {
+          type: Array,
+        },
+        _filteredThreads: {
+          type: Array,
+          computed: '_computeFilteredThreads(_sortedThreads, ' +
+            '_unresolvedOnly, _draftsOnly)',
+        },
+        _unresolvedOnly: {
+          type: Boolean,
+          value: false,
+        },
+        _draftsOnly: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    observers: ['_computeSortedThreads(threads.*)'],
+    static get observers() { return ['_computeSortedThreads(threads.*)']; }
 
     _computeShowDraftToggle(loggedIn) {
       return loggedIn ? 'show' : '';
-    },
+    }
 
     /**
      * Order as follows:
@@ -68,7 +71,7 @@
       const threads = changeRecord.base;
       if (!threads) { return []; }
       this._updateSortedThreads(threads);
-    },
+    }
 
     _updateSortedThreads(threads) {
       this._sortedThreads =
@@ -90,7 +93,7 @@
             }
             return dateCompare ? dateCompare : c1.id.localeCompare(c2.id);
           });
-    },
+    }
 
     _computeFilteredThreads(sortedThreads, unresolvedOnly, draftsOnly) {
       // Polymer 2: check for undefined
@@ -125,15 +128,15 @@
           return c;
         }
       }).map(threadInfo => threadInfo.thread);
-    },
+    }
 
     _getThreadWithSortInfo(thread) {
       const lastComment = thread.comments[thread.comments.length - 1] || {};
 
       const lastNonDraftComment =
           (lastComment.__draft && thread.comments.length > 1) ?
-          thread.comments[thread.comments.length - 2] :
-          lastComment;
+            thread.comments[thread.comments.length - 2] :
+            lastComment;
 
       return {
         thread,
@@ -143,7 +146,7 @@
         hasDraft: !!lastComment.__draft,
         updated: lastComment.updated,
       };
-    },
+    }
 
     removeThread(rootId) {
       for (let i = 0; i < this.threads.length; i++) {
@@ -154,11 +157,11 @@
           return;
         }
       }
-    },
+    }
 
     _handleThreadDiscard(e) {
       this.removeThread(e.detail.rootId);
-    },
+    }
 
     _handleCommentsChanged(e) {
       // Reset threads so thread computations occur on deep array changes to
@@ -167,10 +170,12 @@
 
       this.dispatchEvent(new CustomEvent('thread-list-modified',
           {detail: {rootId: e.detail.rootId, path: e.detail.path}}));
-    },
+    }
 
     _isOnParent(side) {
       return !!side;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrThreadList.is, GrThreadList);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list_test.html b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list_test.html
index ff65aa8..b29246d 100644
--- a/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list_test.html
+++ b/polygerrit-ui/app/elements/change/gr-thread-list/gr-thread-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-thread-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -290,7 +290,6 @@
       assert.equal(element._filteredThreads.includes(thread), true);
     });
 
-
     test('thread removal', () => {
       threadElements[1].fire('thread-discard', {rootId: 'rc2'});
       flushAsynchronousOperations();
diff --git a/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog.js b/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog.js
index 092204a..a3ae1f9 100644
--- a/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog.js
+++ b/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog.js
@@ -27,41 +27,46 @@
     'pull',
   ];
 
-  Polymer({
-    is: 'gr-upload-help-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrUploadHelpDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-upload-help-dialog'; }
     /**
      * Fired when the user presses the close button.
      *
      * @event close
      */
 
-    properties: {
-      revision: Object,
-      targetBranch: String,
-      _commitCommand: {
-        type: String,
-        value: COMMIT_COMMAND,
-        readOnly: true,
-      },
-      _fetchCommand: {
-        type: String,
-        computed: '_computeFetchCommand(revision, ' +
+    static get properties() {
+      return {
+        revision: Object,
+        targetBranch: String,
+        _commitCommand: {
+          type: String,
+          value: COMMIT_COMMAND,
+          readOnly: true,
+        },
+        _fetchCommand: {
+          type: String,
+          computed: '_computeFetchCommand(revision, ' +
             '_preferredDownloadCommand, _preferredDownloadScheme)',
-      },
-      _preferredDownloadCommand: String,
-      _preferredDownloadScheme: String,
-      _pushCommand: {
-        type: String,
-        computed: '_computePushCommand(targetBranch)',
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+        },
+        _preferredDownloadCommand: String,
+        _preferredDownloadScheme: String,
+        _pushCommand: {
+          type: String,
+          computed: '_computePushCommand(targetBranch)',
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this.$.restAPI.getLoggedIn().then(loggedIn => {
         if (loggedIn) {
           return this.$.restAPI.getPreferences();
@@ -72,13 +77,13 @@
           this._preferredDownloadScheme = prefs.download_scheme;
         }
       });
-    },
+    }
 
     _handleCloseTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('close', null, {bubbles: false});
-    },
+    }
 
     _computeFetchCommand(revision, preferredDownloadCommand,
         preferredDownloadScheme) {
@@ -126,10 +131,12 @@
       }
 
       return undefined;
-    },
+    }
 
     _computePushCommand(targetBranch) {
       return PUSH_COMMAND_PREFIX + targetBranch;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrUploadHelpDialog.is, GrUploadHelpDialog);
 })();
diff --git a/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog_test.html b/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog_test.html
index 577b978..76377fb 100644
--- a/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog_test.html
+++ b/polygerrit-ui/app/elements/change/gr-upload-help-dialog/gr-upload-help-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-upload-help-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown.js b/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown.js
index 7cbe988..4f51a02 100644
--- a/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown.js
+++ b/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown.js
@@ -19,29 +19,39 @@
 
   const INTERPOLATE_URL_PATTERN = /\$\{([\w]+)\}/g;
 
-  Polymer({
-    is: 'gr-account-dropdown',
+  /**
+    * @appliesMixin Gerrit.DisplayNameMixin
+    */
+  class GrAccountDropdown extends Polymer.mixinBehaviors( [
+    Gerrit.DisplayNameBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-dropdown'; }
 
-    properties: {
-      account: Object,
-      config: Object,
-      links: {
-        type: Array,
-        computed: '_getLinks(_switchAccountUrl, _path)',
-      },
-      topContent: {
-        type: Array,
-        computed: '_getTopContent(account)',
-      },
-      _path: {
-        type: String,
-        value: '/',
-      },
-      _hasAvatars: Boolean,
-      _switchAccountUrl: String,
-    },
+    static get properties() {
+      return {
+        account: Object,
+        config: Object,
+        links: {
+          type: Array,
+          computed: '_getLinks(_switchAccountUrl, _path)',
+        },
+        topContent: {
+          type: Array,
+          computed: '_getTopContent(account)',
+        },
+        _path: {
+          type: String,
+          value: '/',
+        },
+        _hasAvatars: Boolean,
+        _switchAccountUrl: String,
+      };
+    }
 
     attached() {
+      super.attached();
       this._handleLocationChange();
       this.listen(window, 'location-change', '_handleLocationChange');
       this.$.restAPI.getConfig().then(cfg => {
@@ -54,15 +64,12 @@
         }
         this._hasAvatars = !!(cfg && cfg.plugin && cfg.plugin.has_avatars);
       });
-    },
-
-    behaviors: [
-      Gerrit.DisplayNameBehavior,
-    ],
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'location-change', '_handleLocationChange');
-    },
+    }
 
     _getLinks(switchAccountUrl, path) {
       // Polymer 2: check for undefined
@@ -78,30 +85,32 @@
       }
       links.push({name: 'Sign out', url: '/logout'});
       return links;
-    },
+    }
 
     _getTopContent(account) {
       return [
         {text: this._accountName(account), bold: true},
         {text: account.email ? account.email : ''},
       ];
-    },
+    }
 
     _handleLocationChange() {
       this._path =
           window.location.pathname +
           window.location.search +
           window.location.hash;
-    },
+    }
 
     _interpolateUrl(url, replacements) {
       return url.replace(INTERPOLATE_URL_PATTERN, (match, p1) => {
         return replacements[p1] || '';
       });
-    },
+    }
 
     _accountName(account) {
       return this.getUserName(this.config, account, true);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountDropdown.is, GrAccountDropdown);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown_test.html b/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown_test.html
index e29faa8..9dafb74 100644
--- a/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown_test.html
+++ b/polygerrit-ui/app/elements/core/gr-account-dropdown/gr-account-dropdown_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-dropdown</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog.js b/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog.js
index 8d3b58e..2655140 100644
--- a/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog.js
+++ b/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog.js
@@ -17,21 +17,26 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-error-dialog',
-
+  class GrErrorDialog extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-error-dialog'; }
     /**
      * Fired when the dismiss button is pressed.
      *
      * @event dismiss
      */
 
-    properties: {
-      text: String,
-    },
+    static get properties() {
+      return {
+        text: String,
+      };
+    }
 
     _handleConfirm() {
       this.dispatchEvent(new CustomEvent('dismiss'));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrErrorDialog.is, GrErrorDialog);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog_test.html b/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog_test.html
index 648f8be..dd4a71a 100644
--- a/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog_test.html
+++ b/polygerrit-ui/app/elements/core/gr-error-dialog/gr-error-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-error-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager.js b/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager.js
index 5865e3c..7437187 100644
--- a/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager.js
+++ b/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager.js
@@ -25,40 +25,47 @@
   const TOO_MANY_FILES = 'too many files to find conflicts';
   const AUTHENTICATION_REQUIRED = 'Authentication required\n';
 
-  Polymer({
-    is: 'gr-error-manager',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrErrorManager extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-error-manager'; }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-    ],
-
-    properties: {
+    static get properties() {
+      return {
       /**
        * The ID of the account that was logged in when the app was launched. If
        * not set, then there was no account at launch.
        */
-      knownAccountId: Number,
+        knownAccountId: Number,
 
-      /** @type {?Object} */
-      _alertElement: Object,
-      /** @type {?number} */
-      _hideAlertHandle: Number,
-      _refreshingCredentials: {
-        type: Boolean,
-        value: false,
-      },
+        /** @type {?Object} */
+        _alertElement: Object,
+        /** @type {?number} */
+        _hideAlertHandle: Number,
+        _refreshingCredentials: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * The time (in milliseconds) since the most recent credential check.
        */
-      _lastCredentialCheck: {
-        type: Number,
-        value() { return Date.now(); },
-      },
-    },
+        _lastCredentialCheck: {
+          type: Number,
+          value() { return Date.now(); },
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this.listen(document, 'server-error', '_handleServerError');
       this.listen(document, 'network-error', '_handleNetworkError');
       this.listen(document, 'auth-error', '_handleAuthError');
@@ -66,9 +73,10 @@
       this.listen(document, 'show-error', '_handleShowErrorDialog');
       this.listen(document, 'visibilitychange', '_handleVisibilityChange');
       this.listen(document, 'show-auth-required', '_handleAuthRequired');
-    },
+    }
 
     detached() {
+      super.detached();
       this._clearHideAlertHandle();
       this.unlisten(document, 'server-error', '_handleServerError');
       this.unlisten(document, 'network-error', '_handleNetworkError');
@@ -76,20 +84,20 @@
       this.unlisten(document, 'show-auth-required', '_handleAuthRequired');
       this.unlisten(document, 'visibilitychange', '_handleVisibilityChange');
       this.unlisten(document, 'show-error', '_handleShowErrorDialog');
-    },
+    }
 
     _shouldSuppressError(msg) {
       return msg.includes(TOO_MANY_FILES);
-    },
+    }
 
     _handleAuthRequired() {
       this._showAuthErrorAlert(
           'Log in is required to perform that action.', 'Log in.');
-    },
+    }
 
     _handleAuthError() {
       this._showAuthErrorAlert('Auth error', 'Refresh credentials.');
-    },
+    }
 
     _handleServerError(e) {
       const {request, response} = e.detail;
@@ -113,7 +121,7 @@
             }
             console.error(errorText);
           });
-    },
+    }
 
     _constructServerErrorMsg({errorText, status, statusText, url}) {
       let err = `Error ${status}`;
@@ -122,21 +130,21 @@
       if (errorText) { err += errorText; }
       if (url) { err += `\nEndpoint: ${url}`; }
       return err;
-    },
+    }
 
     _handleShowAlert(e) {
       this._showAlert(e.detail.message, e.detail.action, e.detail.callback,
           e.detail.dismissOnNavigation);
-    },
+    }
 
     _handleNetworkError(e) {
       this._showAlert('Server unavailable');
       console.error(e.detail.error.message);
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     /**
      * @param {string} text
@@ -161,7 +169,7 @@
       const el = this._createToastAlert();
       el.show(text, opt_actionText, opt_actionCallback);
       this._alertElement = el;
-    },
+    }
 
     _hideAlert() {
       if (!this._alertElement) { return; }
@@ -171,14 +179,14 @@
 
       // Remove listener for page navigation, if it exists.
       this.unlisten(document, 'location-change', '_hideAlert');
-    },
+    }
 
     _clearHideAlertHandle() {
       if (this._hideAlertHandle != null) {
         this.cancelAsync(this._hideAlertHandle);
         this._hideAlertHandle = null;
       }
-    },
+    }
 
     _showAuthErrorAlert(errorText, actionText) {
       // TODO(viktard): close alert if it's not for auth error.
@@ -193,13 +201,13 @@
       if (!document.hidden) {
         this._handleVisibilityChange();
       }
-    },
+    }
 
     _createToastAlert() {
       const el = document.createElement('gr-alert');
       el.toast = true;
       return el;
-    },
+    }
 
     _handleVisibilityChange() {
       // Ignore when the page is transitioning to hidden (or hidden is
@@ -216,12 +224,12 @@
         this._lastCredentialCheck = Date.now();
         this.$.restAPI.checkCredentials();
       }
-    },
+    }
 
     _requestCheckLoggedIn() {
       this.debounce(
           'checkLoggedIn', this._checkSignedIn, CHECK_SIGN_IN_INTERVAL_MS);
-    },
+    }
 
     _checkSignedIn() {
       this.$.restAPI.checkCredentials().then(account => {
@@ -242,11 +250,11 @@
           }
         }
       });
-    },
+    }
 
     _reloadPage() {
       window.location.reload();
-    },
+    }
 
     _createLoginPopup() {
       const left = window.screenLeft +
@@ -262,31 +270,33 @@
       window.open(this.getBaseUrl() +
           '/login/%3FcloseAfterLogin', '_blank', options.join(','));
       this.listen(window, 'focus', '_handleWindowFocus');
-    },
+    }
 
     _handleCredentialRefreshed() {
       this.unlisten(window, 'focus', '_handleWindowFocus');
       this._refreshingCredentials = false;
       this._hideAlert();
       this._showAlert('Credentials refreshed.');
-    },
+    }
 
     _handleWindowFocus() {
       this.flushDebouncer('checkLoggedIn');
-    },
+    }
 
     _handleShowErrorDialog(e) {
       this._showErrorDialog(e.detail.message);
-    },
+    }
 
     _handleDismissErrorDialog() {
       this.$.errorOverlay.close();
-    },
+    }
 
     _showErrorDialog(message) {
       this.$.reporting.reportErrorDialog(message);
       this.$.errorDialog.text = message;
       this.$.errorOverlay.open();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrErrorManager.is, GrErrorManager);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager_test.html b/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager_test.html
index 9140c17..84b6717 100644
--- a/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager_test.html
+++ b/polygerrit-ui/app/elements/core/gr-error-manager/gr-error-manager_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-error-manager</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display.js b/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display.js
index 89d1091..2b86170 100644
--- a/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display.js
+++ b/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display.js
@@ -17,20 +17,26 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-key-binding-display',
+  class GrKeyBindingDisplay extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-key-binding-display'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {Array<string>} */
-      binding: Array,
-    },
+        binding: Array,
+      };
+    }
 
     _computeModifiers(binding) {
       return binding.slice(0, binding.length - 1);
-    },
+    }
 
     _computeKey(binding) {
       return binding[binding.length - 1];
-    },
-  });
+    }
+  }
+
+  customElements.define(GrKeyBindingDisplay.is, GrKeyBindingDisplay);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display_test.html b/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display_test.html
index 39c8af8..e0d2d40 100644
--- a/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display_test.html
+++ b/polygerrit-ui/app/elements/core/gr-key-binding-display/gr-key-binding-display_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-key-binding-display</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog.js b/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog.js
index 4bc6e11..e16c975 100644
--- a/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog.js
+++ b/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog.js
@@ -19,60 +19,68 @@
 
   const {ShortcutSection} = window.Gerrit.KeyboardShortcutBinder;
 
-  Polymer({
-    is: 'gr-keyboard-shortcuts-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrKeyboardShortcutsDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-keyboard-shortcuts-dialog'; }
     /**
      * Fired when the user presses the close button.
      *
      * @event close
      */
 
-    properties: {
-      _left: Array,
-      _right: Array,
+    static get properties() {
+      return {
+        _left: Array,
+        _right: Array,
 
-      _propertyBySection: {
-        type: Object,
-        value() {
-          return {
-            [ShortcutSection.EVERYWHERE]: '_everywhere',
-            [ShortcutSection.NAVIGATION]: '_navigation',
-            [ShortcutSection.DASHBOARD]: '_dashboard',
-            [ShortcutSection.CHANGE_LIST]: '_changeList',
-            [ShortcutSection.ACTIONS]: '_actions',
-            [ShortcutSection.REPLY_DIALOG]: '_replyDialog',
-            [ShortcutSection.FILE_LIST]: '_fileList',
-            [ShortcutSection.DIFFS]: '_diffs',
-          };
+        _propertyBySection: {
+          type: Object,
+          value() {
+            return {
+              [ShortcutSection.EVERYWHERE]: '_everywhere',
+              [ShortcutSection.NAVIGATION]: '_navigation',
+              [ShortcutSection.DASHBOARD]: '_dashboard',
+              [ShortcutSection.CHANGE_LIST]: '_changeList',
+              [ShortcutSection.ACTIONS]: '_actions',
+              [ShortcutSection.REPLY_DIALOG]: '_replyDialog',
+              [ShortcutSection.FILE_LIST]: '_fileList',
+              [ShortcutSection.DIFFS]: '_diffs',
+            };
+          },
         },
-      },
-    },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    hostAttributes: {
-      role: 'dialog',
-    },
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'dialog');
+    }
 
     attached() {
+      super.attached();
       this.addKeyboardShortcutDirectoryListener(
           this._onDirectoryUpdated.bind(this));
-    },
+    }
 
     detached() {
+      super.detached();
       this.removeKeyboardShortcutDirectoryListener(
           this._onDirectoryUpdated.bind(this));
-    },
+    }
 
     _handleCloseTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('close', null, {bubbles: false});
-    },
+    }
 
     _onDirectoryUpdated(directory) {
       const left = [];
@@ -122,6 +130,9 @@
 
       this.set('_left', left);
       this.set('_right', right);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrKeyboardShortcutsDialog.is,
+      GrKeyboardShortcutsDialog);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog_test.html b/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog_test.html
index 1a3d6c7..b713aa1 100644
--- a/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog_test.html
+++ b/polygerrit-ui/app/elements/core/gr-keyboard-shortcuts-dialog/gr-keyboard-shortcuts-dialog_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-key-binding-display</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.html b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.html
index fe8384e..d29858e 100644
--- a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.html
+++ b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.html
@@ -90,7 +90,7 @@
       }
       gr-smart-search {
         flex-grow: 1;
-        margin-left: var(--spacing-m);
+        margin: 0 var(--spacing-m);
         max-width: 500px;
       }
       gr-dropdown,
diff --git a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.js b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.js
index 773ad68..1ae1e93 100644
--- a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.js
+++ b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header.js
@@ -69,94 +69,107 @@
     'CUSTOM_EXTENSION',
   ]);
 
-  Polymer({
-    is: 'gr-main-header',
+  /**
+    * @appliesMixin Gerrit.AdminNavMixin
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.DocsUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrMainHeader extends Polymer.mixinBehaviors( [
+    Gerrit.AdminNavBehavior,
+    Gerrit.BaseUrlBehavior,
+    Gerrit.DocsUrlBehavior,
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-main-header'; }
 
-    hostAttributes: {
-      role: 'banner',
-    },
-
-    properties: {
-      searchQuery: {
-        type: String,
-        notify: true,
-      },
-      loggedIn: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-      loading: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-
-      /** @type {?Object} */
-      _account: Object,
-      _adminLinks: {
-        type: Array,
-        value() { return []; },
-      },
-      _defaultLinks: {
-        type: Array,
-        value() {
-          return DEFAULT_LINKS;
+    static get properties() {
+      return {
+        searchQuery: {
+          type: String,
+          notify: true,
         },
-      },
-      _docBaseUrl: {
-        type: String,
-        value: null,
-      },
-      _links: {
-        type: Array,
-        computed: '_computeLinks(_defaultLinks, _userLinks, _adminLinks, ' +
+        loggedIn: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+        loading: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+
+        /** @type {?Object} */
+        _account: Object,
+        _adminLinks: {
+          type: Array,
+          value() { return []; },
+        },
+        _defaultLinks: {
+          type: Array,
+          value() {
+            return DEFAULT_LINKS;
+          },
+        },
+        _docBaseUrl: {
+          type: String,
+          value: null,
+        },
+        _links: {
+          type: Array,
+          computed: '_computeLinks(_defaultLinks, _userLinks, _adminLinks, ' +
             '_topMenus, _docBaseUrl)',
-      },
-      _loginURL: {
-        type: String,
-        value: '/login',
-      },
-      _userLinks: {
-        type: Array,
-        value() { return []; },
-      },
-      _topMenus: {
-        type: Array,
-        value() { return []; },
-      },
-      _registerText: {
-        type: String,
-        value: 'Sign up',
-      },
-      _registerURL: {
-        type: String,
-        value: null,
-      },
-    },
+        },
+        _loginURL: {
+          type: String,
+          value: '/login',
+        },
+        _userLinks: {
+          type: Array,
+          value() { return []; },
+        },
+        _topMenus: {
+          type: Array,
+          value() { return []; },
+        },
+        _registerText: {
+          type: String,
+          value: 'Sign up',
+        },
+        _registerURL: {
+          type: String,
+          value: null,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.AdminNavBehavior,
-      Gerrit.BaseUrlBehavior,
-      Gerrit.DocsUrlBehavior,
-      Gerrit.FireBehavior,
-    ],
+    static get observers() {
+      return [
+        '_accountLoaded(_account)',
+      ];
+    }
 
-    observers: [
-      '_accountLoaded(_account)',
-    ],
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'banner');
+    }
 
     attached() {
+      super.attached();
       this._loadAccount();
       this._loadConfig();
       this.listen(window, 'location-change', '_handleLocationChange');
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'location-change', '_handleLocationChange');
-    },
+    }
 
     reload() {
       this._loadAccount();
-    },
+    }
 
     _handleLocationChange(e) {
       const baseUrl = this.getBaseUrl();
@@ -173,11 +186,11 @@
             window.location.search +
             window.location.hash);
       }
-    },
+    }
 
     _computeRelativeURL(path) {
       return '//' + window.location.host + this.getBaseUrl() + path;
-    },
+    }
 
     _computeLinks(defaultLinks, userLinks, adminLinks, topMenus, docBaseUrl) {
       // Polymer 2: check for undefined
@@ -232,7 +245,7 @@
         }
       }
       return links;
-    },
+    }
 
     _getDocLinks(docBaseUrl, docLinks) {
       if (!docBaseUrl || !docLinks) {
@@ -249,7 +262,7 @@
           target: '_blank',
         };
       });
-    },
+    }
 
     _loadAccount() {
       this.loading = true;
@@ -273,7 +286,7 @@
               this._adminLinks = res.links;
             });
       });
-    },
+    }
 
     _loadConfig() {
       this.$.restAPI.getConfig()
@@ -282,7 +295,7 @@
             return this.getDocsBaseUrl(config, this.$.restAPI);
           })
           .then(docBaseUrl => { this._docBaseUrl = docBaseUrl; });
-    },
+    }
 
     _accountLoaded(account) {
       if (!account) { return; }
@@ -290,7 +303,7 @@
       this.$.restAPI.getPreferences().then(prefs => {
         this._userLinks = prefs.my.map(this._fixCustomMenuItem);
       });
-    },
+    }
 
     _retrieveRegisterURL(config) {
       if (AUTH_TYPES_WITH_REGISTER_URL.has(config.auth.auth_type)) {
@@ -299,11 +312,11 @@
           this._registerText = config.auth.register_text;
         }
       }
-    },
+    }
 
     _computeIsInvisible(registerURL) {
       return registerURL ? '' : 'invisible';
-    },
+    }
 
     _fixCustomMenuItem(linkObj) {
       // Normalize all urls to PolyGerrit style.
@@ -321,17 +334,17 @@
       delete linkObj.target;
 
       return linkObj;
-    },
+    }
 
     _generateSettingsLink() {
       return this.getBaseUrl() + '/settings/';
-    },
+    }
 
     _onMobileSearchTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('mobile-search', null, {bubbles: false});
-    },
+    }
 
     _computeLinkGroupClass(linkGroup) {
       if (linkGroup && linkGroup.class) {
@@ -339,6 +352,8 @@
       }
 
       return '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrMainHeader.is, GrMainHeader);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header_test.html b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header_test.html
index ef14370..46e7d32 100644
--- a/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header_test.html
+++ b/polygerrit-ui/app/elements/core/gr-main-header/gr-main-header_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-main-header</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -78,7 +78,7 @@
           'none');
       assert.notEqual(getComputedStyle(element.$$('gr-account-dropdown'))
           .display,
-          'none');
+      'none');
       assert.notEqual(getComputedStyle(element.$$('.settingsButton')).display,
           'none');
     });
@@ -116,28 +116,28 @@
           /* userLinks= */[],
           adminLinks,
           /* topMenus= */[],
-          /* docBaseUrl= */ '',
+          /* docBaseUrl= */ ''
       ),
-          defaultLinks.concat({
-            title: 'Browse',
-            links: adminLinks,
-          }));
+      defaultLinks.concat({
+        title: 'Browse',
+        links: adminLinks,
+      }));
       assert.deepEqual(element._computeLinks(
           defaultLinks,
           userLinks,
           adminLinks,
           /* topMenus= */[],
           /* docBaseUrl= */ ''
-        ),
-          defaultLinks.concat([
-            {
-              title: 'Your',
-              links: userLinks,
-            },
-            {
-              title: 'Browse',
-              links: adminLinks,
-            }])
+      ),
+      defaultLinks.concat([
+        {
+          title: 'Your',
+          links: userLinks,
+        },
+        {
+          title: 'Browse',
+          links: adminLinks,
+        }])
       );
     });
 
@@ -185,7 +185,7 @@
           /* userLinks= */ [],
           adminLinks,
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Browse',
         links: adminLinks,
@@ -221,7 +221,7 @@
           /* userLinks= */ [],
           adminLinks,
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Browse',
         links: adminLinks,
@@ -260,7 +260,7 @@
           /* userLinks= */ [],
           adminLinks,
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Browse',
         links: adminLinks,
@@ -297,7 +297,7 @@
           /* userLinks= */ [],
           /* adminLinks= */ [],
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Faves',
         links: defaultLinks[0].links.concat([{
@@ -328,7 +328,7 @@
           userLinks,
           /* adminLinks= */ [],
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Your',
         links: userLinks.concat([{
@@ -359,7 +359,7 @@
           /* userLinks= */ [],
           adminLinks,
           topMenus,
-          /* baseDocUrl= */ '',
+          /* baseDocUrl= */ ''
       ), [{
         title: 'Browse',
         links: adminLinks.concat([{
diff --git a/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation.html b/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation.html
index 9eaf603..1d8f04b 100644
--- a/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation.html
+++ b/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation.html
@@ -732,11 +732,11 @@
       getUserDashboard(user = 'self', sections = DEFAULT_SECTIONS,
           title = '') {
         sections = sections
-          .filter(section => (user === 'self' || !section.selfOnly))
-          .map(section => Object.assign({}, section, {
-            name: section.name,
-            query: section.query.replace(USER_PLACEHOLDER_PATTERN, user),
-          }));
+            .filter(section => (user === 'self' || !section.selfOnly))
+            .map(section => Object.assign({}, section, {
+              name: section.name,
+              query: section.query.replace(USER_PLACEHOLDER_PATTERN, user),
+            }));
         return {title, sections};
       },
     };
diff --git a/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation_test.html b/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation_test.html
index 73ce86a..ca44430 100644
--- a/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation_test.html
+++ b/polygerrit-ui/app/elements/core/gr-navigation/gr-navigation_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-navigation</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting.js b/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting.js
index 30d322e..d169728 100644
--- a/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting.js
+++ b/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting.js
@@ -41,14 +41,6 @@
     DETECTED: 'Extension detected',
   };
 
-  // Page visibility related constants.
-  const PAGE_VISIBILITY = {
-    TYPE: 'lifecycle',
-    CATEGORY: 'Page Visibility',
-    // Reported events - alphabetize below.
-    STARTED_HIDDEN: 'hidden',
-  };
-
   // Navigation reporting constants.
   const NAVIGATION = {
     TYPE: 'nav-report',
@@ -107,8 +99,10 @@
 
   const pending = [];
 
+  // Variables that hold context info in global scope
   const loadedPlugins = [];
   const detectedExtensions = [];
+  let reportRepoName = undefined;
 
   const onError = function(oldOnError, msg, url, line, column, error) {
     if (oldOnError) {
@@ -148,6 +142,25 @@
   };
   catchErrors();
 
+  // PerformanceObserver interface is a browser API.
+  if (window.PerformanceObserver) {
+    const supportedEntryTypes = PerformanceObserver.supportedEntryTypes || [];
+    // Safari doesn't support longtask yet
+    if (supportedEntryTypes.includes('longtask')) {
+      const catchLongJsTasks = new PerformanceObserver(list => {
+        for (const task of list.getEntries()) {
+          // We are interested in longtask longer than 200 ms (default is 50 ms)
+          if (task.duration > 200) {
+            GrReporting.prototype.reporter(TIMING.TYPE,
+                TIMING.CATEGORY_UI_LATENCY, `Task ${task.name}`,
+                Math.round(task.duration), false);
+          }
+        }
+      });
+      catchLongJsTasks.observe({entryTypes: ['longtask']});
+    }
+  }
+
   // The Polymer pass of JSCompiler requires this to be reassignable
   // eslint-disable-next-line prefer-const
   let GrReporting = Polymer({
@@ -188,7 +201,13 @@
     reporter(...args) {
       const report = (this._isMetricsPluginLoaded() && !pending.length) ?
         this.defaultReporter : this.cachingReporter;
-      args.splice(4, 0, loadedPlugins, detectedExtensions);
+      const contextInfo = {
+        loadedPlugins,
+        detectedExtensions,
+        repoName: reportRepoName,
+        isInBackgroundTab: document.visibilityState === 'hidden',
+      };
+      args.splice(4, 0, contextInfo);
       report.apply(this, args);
     },
 
@@ -198,22 +217,27 @@
      * @param {string} category
      * @param {string} eventName
      * @param {string|number} eventValue
-     * @param {Array} plugins
-     * @param {Array} extensions
+     * @param {Object} contextInfo
      * @param {boolean|undefined} opt_noLog If true, the event will not be
      *     logged to the JS console.
      */
-    defaultReporter(type, category, eventName, eventValue,
-        loadedPlugins, detectedExtensions, opt_noLog) {
+    defaultReporter(type, category, eventName, eventValue, contextInfo,
+        opt_noLog) {
       const detail = {
         type,
         category,
         name: eventName,
         value: eventValue,
       };
-      if (category === TIMING.CATEGORY_UI_LATENCY) {
-        detail.loadedPlugins = loadedPlugins;
-        detail.detectedExtensions = detectedExtensions;
+      if (category === TIMING.CATEGORY_UI_LATENCY && contextInfo) {
+        detail.loadedPlugins = contextInfo.loadedPlugins;
+        detail.detectedExtensions = contextInfo.detectedExtensions;
+      }
+      if (contextInfo && contextInfo.repoName) {
+        detail.repoName = contextInfo.repoName;
+      }
+      if (contextInfo && contextInfo.isInBackgroundTab !== undefined) {
+        detail.inBackgroundTab = contextInfo.isInBackgroundTab;
       }
       document.dispatchEvent(new CustomEvent(type, {detail}));
       if (opt_noLog) { return; }
@@ -235,43 +259,39 @@
      * @param {string} category
      * @param {string} eventName
      * @param {string|number} eventValue
-     * @param {Array} plugins
-     * @param {Array} extensions
+     * @param {Object} contextInfo
      * @param {boolean|undefined} opt_noLog If true, the event will not be
      *     logged to the JS console.
      */
-    cachingReporter(type, category, eventName, eventValue,
-        plugins, extensions, opt_noLog) {
+    cachingReporter(type, category, eventName, eventValue, contextInfo,
+        opt_noLog) {
       if (type === ERROR.TYPE && category === ERROR.CATEGORY) {
         console.error(eventValue && eventValue.error || eventName);
       }
       if (this._isMetricsPluginLoaded()) {
         if (pending.length) {
           for (const args of pending.splice(0)) {
-            this.reporter(...args);
+            this.defaultReporter(...args);
           }
         }
-        this.reporter(type, category, eventName, eventValue,
-            plugins, extensions, opt_noLog);
+        this.defaultReporter(type, category, eventName, eventValue, contextInfo,
+            opt_noLog);
       } else {
-        pending.push([type, category, eventName, eventValue,
-          plugins, extensions, opt_noLog]);
+        pending.push([type, category, eventName, eventValue, contextInfo,
+          opt_noLog]);
       }
     },
 
     /**
      * User-perceived app start time, should be reported when the app is ready.
      */
-    appStarted(hidden) {
+    appStarted() {
       this.timeEnd(TIMING.APP_STARTED);
-      if (hidden) {
-        this.reporter(PAGE_VISIBILITY.TYPE, PAGE_VISIBILITY.CATEGORY,
-            PAGE_VISIBILITY.STARTED_HIDDEN);
-      }
     },
 
     /**
-     * Page load time, should be reported at any time after navigation.
+     * Page load time and other metrics, should be reported at any time
+     * after navigation.
      */
     pageLoaded() {
       if (this.performanceTiming.loadEventEnd === 0) {
@@ -281,7 +301,35 @@
         const loadTime = this.performanceTiming.loadEventEnd -
             this.performanceTiming.navigationStart;
         this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
-            TIMING.PAGE_LOADED, loadTime);
+            TIMING.PAGE_LOADED, loadTime, true);
+
+        const requestStart = this.performanceTiming.requestStart -
+            this.performanceTiming.navigationStart;
+        this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
+            'requestStart', requestStart, true);
+
+        const responseEnd = this.performanceTiming.responseEnd -
+            this.performanceTiming.navigationStart;
+        this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
+            'responseEnd', responseEnd, true);
+
+        const domLoading = this.performanceTiming.domLoading -
+          this.performanceTiming.navigationStart;
+        this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
+            'domLoading', domLoading, true);
+
+        const domContentLoadedEventStart =
+          this.performanceTiming.domContentLoadedEventStart -
+          this.performanceTiming.navigationStart;
+        this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
+            'domContentLoadedEventStart', domContentLoadedEventStart, true);
+
+        if (this.performanceTiming.redirectEnd > 0) {
+          const redirectEnd = this.performanceTiming.redirectEnd -
+              this.performanceTiming.navigationStart;
+          this.reporter(TIMING.TYPE, TIMING.CATEGORY_UI_LATENCY,
+              'redirectEnd', redirectEnd, true);
+        }
       }
     },
 
@@ -296,6 +344,7 @@
       this.time(TIMER.DIFF_VIEW_DISPLAYED);
       this.time(TIMER.DIFF_VIEW_LOAD_FULL);
       this.time(TIMER.FILE_LIST_DISPLAYED);
+      reportRepoName = undefined;
     },
 
     locationChanged(page) {
@@ -518,6 +567,10 @@
       this.reporter(ERROR_DIALOG.TYPE, ERROR_DIALOG.CATEGORY,
           'ErrorDialog: ' + message, {error: new Error(message)});
     },
+
+    setRepoName(repoName) {
+      reportRepoName = repoName;
+    },
   });
 
   window.GrReporting = GrReporting;
diff --git a/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting_test.html b/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting_test.html
index c357979..c2c0297 100644
--- a/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting_test.html
+++ b/polygerrit-ui/app/elements/core/gr-reporting/gr-reporting_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reporting</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -64,15 +64,11 @@
 
     test('appStarted', () => {
       sandbox.stub(element, 'now').returns(42);
-      element.appStarted(true);
+      element.appStarted();
       assert.isTrue(
           element.reporter.calledWithExactly(
               'timing-report', 'UI Latency', 'App Started', 42
-      ));
-      assert.isTrue(
-          element.reporter.calledWithExactly(
-              'lifecycle', 'Page Visibility', 'hidden'
-      ));
+          ));
     });
 
     test('WebComponentsReady', () => {
@@ -88,7 +84,8 @@
       assert.isTrue(
           element.reporter.calledWithExactly(
               'timing-report', 'UI Latency', 'Page Loaded',
-              fakePerformance.loadEventEnd - fakePerformance.navigationStart)
+              fakePerformance.loadEventEnd - fakePerformance.navigationStart,
+              true)
       );
     });
 
@@ -289,9 +286,9 @@
         // element.pluginLoaded('foo');
         element.time('timeAction');
         element.timeEnd('timeAction');
-        assert.isTrue(element.defaultReporter.getCall(1).calledWith(
+        assert.isTrue(element.defaultReporter.getCall(1).calledWithMatch(
             'timing-report', 'UI Latency', 'timeAction', 0,
-            ['metrics-xyz1']
+            {loadedPlugins: ['metrics-xyz1']}
         ));
       });
 
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router.js b/polygerrit-ui/app/elements/core/gr-router/gr-router.js
index b0fc5b3..a3bf6c9 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router.js
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router.js
@@ -207,38 +207,46 @@
     });
   })();
 
-  Polymer({
-    is: 'gr-router',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrRouter extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-router'; }
 
-    properties: {
-      _app: {
-        type: Object,
-        value: app,
-      },
-      _isRedirecting: Boolean,
-      // This variable is to differentiate between internal navigation (false)
-      // and for first navigation in app after loaded from server (true).
-      _isInitialLoad: {
-        type: Boolean,
-        value: true,
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    static get properties() {
+      return {
+        _app: {
+          type: Object,
+          value: app,
+        },
+        _isRedirecting: Boolean,
+        // This variable is to differentiate between internal navigation (false)
+        // and for first navigation in app after loaded from server (true).
+        _isInitialLoad: {
+          type: Boolean,
+          value: true,
+        },
+      };
+    }
 
     start() {
       if (!this._app) { return; }
       this._startRouter();
-    },
+    }
 
     _setParams(params) {
       this._appElement().params = params;
-    },
+    }
 
     _appElement() {
       // In Polymer2 you have to reach through the shadow root of the app
@@ -248,12 +256,12 @@
       return document.getElementById('app-element') ||
           document.getElementById('app').shadowRoot.getElementById(
               'app-element');
-    },
+    }
 
     _redirect(url) {
       this._isRedirecting = true;
       page.redirect(url);
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -285,7 +293,7 @@
       }
 
       return base + url;
-    },
+    }
 
     _generateWeblinks(params) {
       const type = params.type;
@@ -299,7 +307,7 @@
         default:
           console.warn(`Unsupported weblink ${type}!`);
       }
-    },
+    }
 
     _getPatchSetWeblink(params) {
       const {commit, options} = params;
@@ -311,7 +319,7 @@
       } else {
         return {name, url: weblink.url};
       }
-    },
+    }
 
     _firstCodeBrowserWeblink(weblinks) {
       // This is an ordered whitelist of web link types that provide direct
@@ -323,8 +331,7 @@
         if (weblink) { return weblink; }
       }
       return null;
-    },
-
+    }
 
     _getBrowseCommitWeblink(weblinks, config) {
       if (!weblinks) { return null; }
@@ -340,7 +347,7 @@
       }
       if (!weblink) { return null; }
       return weblink;
-    },
+    }
 
     _getChangeWeblinks({repo, commit, options: {weblinks, config}}) {
       if (!weblinks || !weblinks.length) return [];
@@ -349,11 +356,11 @@
         !commitWeblink ||
         !commitWeblink.name ||
         weblink.name !== commitWeblink.name);
-    },
+    }
 
     _getFileWebLinks({repo, commit, file, options: {weblinks}}) {
       return weblinks;
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -400,7 +407,7 @@
       }
 
       return '/q/' + operators.join('+') + offsetExpr;
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -424,7 +431,7 @@
       } else {
         return `/c/${params.changeNum}${suffix}`;
       }
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -449,7 +456,7 @@
         // User dashboard.
         return `/dashboard/${params.user || 'self'}`;
       }
-    },
+    }
 
     /**
      * @param {!Array<!{name: string, query: string}>} sections
@@ -461,12 +468,12 @@
         // If there is a repo name provided, make sure to substitute it into the
         // ${repo} (or legacy ${project}) query tokens.
         const query = opt_repoName ?
-            section.query.replace(REPO_TOKEN_PATTERN, opt_repoName) :
-            section.query;
+          section.query.replace(REPO_TOKEN_PATTERN, opt_repoName) :
+          section.query;
         return encodeURIComponent(section.name) + '=' +
             encodeURIComponent(query);
       });
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -492,7 +499,7 @@
       } else {
         return `/c/${params.changeNum}${suffix}`;
       }
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -506,7 +513,7 @@
         url += ',audit-log';
       }
       return url;
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -526,7 +533,7 @@
         url += ',dashboards';
       }
       return url;
-    },
+    }
 
     /**
      * @param {!Object} params
@@ -534,7 +541,7 @@
      */
     _generateSettingsUrl(params) {
       return '/settings';
-    },
+    }
 
     /**
      * Given an object of parameters, potentially including a `patchNum` or a
@@ -548,7 +555,7 @@
       if (params.patchNum) { range = '' + params.patchNum; }
       if (params.basePatchNum) { range = params.basePatchNum + '..' + range; }
       return range;
-    },
+    }
 
     /**
      * Given a set of params without a project, gets the project from the rest
@@ -572,7 +579,7 @@
             this._normalizePatchRangeParams(params);
             this._redirect(this._generateUrl(params));
           });
-    },
+    }
 
     /**
      * Normalizes the params object, and determines if the URL needs to be
@@ -601,7 +608,7 @@
         params.basePatchNum = null;
       }
       return needsRedirect;
-    },
+    }
 
     /**
      * Redirect the user to login using the given return-URL for redirection
@@ -612,7 +619,7 @@
       const basePath = this.getBaseUrl() || '';
       page(
           '/login/' + encodeURIComponent(returnUrl.substring(basePath.length)));
-    },
+    }
 
     /**
      * Hashes parsed by page.js exclude "inner" hashes, so a URL like "/a#b#c"
@@ -623,7 +630,7 @@
      */
     _getHashFromCanonicalPath(canonicalPath) {
       return canonicalPath.split('#').slice(1).join('#');
-    },
+    }
 
     _parseLineAddress(hash) {
       const match = hash.match(LINE_ADDRESS_PATTERN);
@@ -632,7 +639,7 @@
         leftSide: !!match[1],
         lineNum: parseInt(match[2], 10),
       };
-    },
+    }
 
     /**
      * Check to see if the user is logged in and return a promise that only
@@ -651,12 +658,12 @@
           return Promise.reject(new Error());
         }
       });
-    },
+    }
 
     /**  Page.js middleware that warms the REST API's logged-in cache line. */
     _loadUserMiddleware(ctx, next) {
       this.$.restAPI.getLoggedIn().then(() => { next(); });
-    },
+    }
 
     /**
      * Map a route to a method on the router.
@@ -683,7 +690,7 @@
           this._redirectIfNotLoggedIn(data) : Promise.resolve();
         promise.then(() => { this[handlerName](data); });
       });
-    },
+    }
 
     _startRouter() {
       const base = this.getBaseUrl();
@@ -879,7 +886,7 @@
       this._mapRoute(RoutePattern.DEFAULT, '_handleDefaultRoute');
 
       page.start();
-    },
+    }
 
     /**
      * @param {!Object} data
@@ -920,7 +927,7 @@
           this._redirect('/q/status:open');
         }
       });
-    },
+    }
 
     /**
      * Decode an application/x-www-form-urlencoded string.
@@ -930,7 +937,7 @@
      */
     _decodeQueryString(qs) {
       return decodeURIComponent(qs.replace(PLUS_PATTERN, ' '));
-    },
+    }
 
     /**
      * Parse a query string (e.g. window.location.search) into an array of
@@ -962,7 +969,7 @@
         }
       });
       return params;
-    },
+    }
 
     /**
      * Handle dashboard routes. These may be user, or project dashboards.
@@ -987,7 +994,7 @@
           });
         }
       });
-    },
+    }
 
     /**
      * Handle custom dashboard routes.
@@ -1039,30 +1046,32 @@
       // Redirect /dashboard/ -> /dashboard/self.
       this._redirect('/dashboard/self');
       return Promise.resolve();
-    },
+    }
 
     _handleProjectDashboardRoute(data) {
+      const project = data.params[0];
       this._setParams({
         view: Gerrit.Nav.View.DASHBOARD,
-        project: data.params[0],
+        project,
         dashboard: decodeURIComponent(data.params[1]),
       });
-    },
+      this.$.reporting.setRepoName(project);
+    }
 
     _handleGroupInfoRoute(data) {
       this._redirect('/admin/groups/' + encodeURIComponent(data.params[0]));
-    },
+    }
 
     _handleGroupSelfRedirectRoute(data) {
       this._redirect('/settings/#Groups');
-    },
+    }
 
     _handleGroupRoute(data) {
       this._setParams({
         view: Gerrit.Nav.View.GROUP,
         groupId: data.params[0],
       });
-    },
+    }
 
     _handleGroupAuditLogRoute(data) {
       this._setParams({
@@ -1070,7 +1079,7 @@
         detail: Gerrit.Nav.GroupDetailView.LOG,
         groupId: data.params[0],
       });
-    },
+    }
 
     _handleGroupMembersRoute(data) {
       this._setParams({
@@ -1078,7 +1087,7 @@
         detail: Gerrit.Nav.GroupDetailView.MEMBERS,
         groupId: data.params[0],
       });
-    },
+    }
 
     _handleGroupListOffsetRoute(data) {
       this._setParams({
@@ -1088,7 +1097,7 @@
         filter: null,
         openCreateModal: data.hash === 'create',
       });
-    },
+    }
 
     _handleGroupListFilterOffsetRoute(data) {
       this._setParams({
@@ -1097,7 +1106,7 @@
         offset: data.params.offset,
         filter: data.params.filter,
       });
-    },
+    }
 
     _handleGroupListFilterRoute(data) {
       this._setParams({
@@ -1105,7 +1114,7 @@
         adminView: 'gr-admin-group-list',
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handleProjectsOldRoute(data) {
       let params = '';
@@ -1118,31 +1127,37 @@
       }
 
       this._redirect(`/admin/repos/${params}`);
-    },
+    }
 
     _handleRepoCommandsRoute(data) {
+      const repo = data.params[0];
       this._setParams({
         view: Gerrit.Nav.View.REPO,
         detail: Gerrit.Nav.RepoDetailView.COMMANDS,
-        repo: data.params[0],
+        repo,
       });
-    },
+      this.$.reporting.setRepoName(repo);
+    }
 
     _handleRepoAccessRoute(data) {
+      const repo = data.params[0];
       this._setParams({
         view: Gerrit.Nav.View.REPO,
         detail: Gerrit.Nav.RepoDetailView.ACCESS,
-        repo: data.params[0],
+        repo,
       });
-    },
+      this.$.reporting.setRepoName(repo);
+    }
 
     _handleRepoDashboardsRoute(data) {
+      const repo = data.params[0];
       this._setParams({
         view: Gerrit.Nav.View.REPO,
         detail: Gerrit.Nav.RepoDetailView.DASHBOARDS,
-        repo: data.params[0],
+        repo,
       });
-    },
+      this.$.reporting.setRepoName(repo);
+    }
 
     _handleBranchListOffsetRoute(data) {
       this._setParams({
@@ -1152,7 +1167,7 @@
         offset: data.params[2] || 0,
         filter: null,
       });
-    },
+    }
 
     _handleBranchListFilterOffsetRoute(data) {
       this._setParams({
@@ -1162,7 +1177,7 @@
         offset: data.params.offset,
         filter: data.params.filter,
       });
-    },
+    }
 
     _handleBranchListFilterRoute(data) {
       this._setParams({
@@ -1171,7 +1186,7 @@
         repo: data.params.repo,
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handleTagListOffsetRoute(data) {
       this._setParams({
@@ -1181,7 +1196,7 @@
         offset: data.params[2] || 0,
         filter: null,
       });
-    },
+    }
 
     _handleTagListFilterOffsetRoute(data) {
       this._setParams({
@@ -1191,7 +1206,7 @@
         offset: data.params.offset,
         filter: data.params.filter,
       });
-    },
+    }
 
     _handleTagListFilterRoute(data) {
       this._setParams({
@@ -1200,7 +1215,7 @@
         repo: data.params.repo,
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handleRepoListOffsetRoute(data) {
       this._setParams({
@@ -1210,7 +1225,7 @@
         filter: null,
         openCreateModal: data.hash === 'create',
       });
-    },
+    }
 
     _handleRepoListFilterOffsetRoute(data) {
       this._setParams({
@@ -1219,7 +1234,7 @@
         offset: data.params.offset,
         filter: data.params.filter,
       });
-    },
+    }
 
     _handleRepoListFilterRoute(data) {
       this._setParams({
@@ -1227,26 +1242,28 @@
         adminView: 'gr-repo-list',
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handleCreateProjectRoute(data) {
       // Redirects the legacy route to the new route, which displays the project
       // list with a hash 'create'.
       this._redirect('/admin/repos#create');
-    },
+    }
 
     _handleCreateGroupRoute(data) {
       // Redirects the legacy route to the new route, which displays the group
       // list with a hash 'create'.
       this._redirect('/admin/groups#create');
-    },
+    }
 
     _handleRepoRoute(data) {
+      const repo = data.params[0];
       this._setParams({
         view: Gerrit.Nav.View.REPO,
-        repo: data.params[0],
+        repo,
       });
-    },
+      this.$.reporting.setRepoName(repo);
+    }
 
     _handlePluginListOffsetRoute(data) {
       this._setParams({
@@ -1255,7 +1272,7 @@
         offset: data.params[1] || 0,
         filter: null,
       });
-    },
+    }
 
     _handlePluginListFilterOffsetRoute(data) {
       this._setParams({
@@ -1264,7 +1281,7 @@
         offset: data.params.offset,
         filter: data.params.filter,
       });
-    },
+    }
 
     _handlePluginListFilterRoute(data) {
       this._setParams({
@@ -1272,14 +1289,14 @@
         adminView: 'gr-plugin-list',
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handlePluginListRoute(data) {
       this._setParams({
         view: Gerrit.Nav.View.ADMIN,
         adminView: 'gr-plugin-list',
       });
-    },
+    }
 
     _handleQueryRoute(data) {
       this._setParams({
@@ -1287,15 +1304,15 @@
         query: data.params[0],
         offset: data.params[2],
       });
-    },
+    }
 
     _handleQueryLegacySuffixRoute(ctx) {
       this._redirect(ctx.path.replace(LEGACY_QUERY_SUFFIX_PATTERN, ''));
-    },
+    }
 
     _handleChangeNumberLegacyRoute(ctx) {
       this._redirect('/c/' + encodeURIComponent(ctx.params[0]));
-    },
+    }
 
     _handleChangeRoute(ctx) {
       // Parameter order is based on the regex group number matched.
@@ -1307,8 +1324,9 @@
         view: Gerrit.Nav.View.CHANGE,
       };
 
+      this.$.reporting.setRepoName(params.project);
       this._redirectOrNavigate(params);
-    },
+    }
 
     _handleDiffRoute(ctx) {
       // Parameter order is based on the regex group number matched.
@@ -1326,9 +1344,9 @@
         params.leftSide = address.leftSide;
         params.lineNum = address.lineNum;
       }
-
+      this.$.reporting.setRepoName(params.project);
       this._redirectOrNavigate(params);
-    },
+    }
 
     _handleChangeLegacyRoute(ctx) {
       // Parameter order is based on the regex group number matched.
@@ -1341,11 +1359,11 @@
       };
 
       this._normalizeLegacyRouteParams(params);
-    },
+    }
 
     _handleLegacyLinenum(ctx) {
       this._redirect(ctx.path.replace(LEGACY_LINENUM_PATTERN, '#$1'));
-    },
+    }
 
     _handleDiffLegacyRoute(ctx) {
       // Parameter order is based on the regex group number matched.
@@ -1364,29 +1382,33 @@
       }
 
       this._normalizeLegacyRouteParams(params);
-    },
+    }
 
     _handleDiffEditRoute(ctx) {
       // Parameter order is based on the regex group number matched.
+      const project = ctx.params[0];
       this._redirectOrNavigate({
-        project: ctx.params[0],
+        project,
         changeNum: ctx.params[1],
         patchNum: ctx.params[2],
         path: ctx.params[3],
         view: Gerrit.Nav.View.EDIT,
       });
-    },
+      this.$.reporting.setRepoName(project);
+    }
 
     _handleChangeEditRoute(ctx) {
       // Parameter order is based on the regex group number matched.
+      const project = ctx.params[0];
       this._redirectOrNavigate({
-        project: ctx.params[0],
+        project,
         changeNum: ctx.params[1],
         patchNum: ctx.params[3],
         view: Gerrit.Nav.View.CHANGE,
         edit: true,
       });
-    },
+      this.$.reporting.setRepoName(project);
+    }
 
     /**
      * Normalize the patch range params for a the change or diff view and
@@ -1399,16 +1421,16 @@
       } else {
         this._setParams(params);
       }
-    },
+    }
 
     _handleAgreementsRoute() {
       this._redirect('/settings/#Agreements');
-    },
+    }
 
     _handleNewAgreementsRoute(data) {
       data.params.view = Gerrit.Nav.View.AGREEMENTS;
       this._setParams(data.params);
-    },
+    }
 
     _handleSettingsLegacyRoute(data) {
       // email tokens may contain '+' but no space.
@@ -1419,11 +1441,11 @@
         view: Gerrit.Nav.View.SETTINGS,
         emailToken: token,
       });
-    },
+    }
 
     _handleSettingsRoute(data) {
       this._setParams({view: Gerrit.Nav.View.SETTINGS});
-    },
+    }
 
     _handleRegisterRoute(ctx) {
       this._setParams({justRegistered: true});
@@ -1434,7 +1456,7 @@
 
       if (path[0] !== '/') { return; }
       this._redirect(this.getBaseUrl() + path);
-    },
+    }
 
     /**
      * Handler for routes that should pass through the router and not be caught
@@ -1442,8 +1464,7 @@
      */
     _handlePassThroughRoute() {
       location.reload();
-    },
-
+    }
 
     /**
      * URL may sometimes have /+/ encoded to / /.
@@ -1453,26 +1474,26 @@
       let hash = this._getHashFromCanonicalPath(ctx.canonicalPath);
       if (hash.length) { hash = '#' + hash; }
       this._redirect(`/c/${ctx.params[0]}/+/${ctx.params[1]}${hash}`);
-    },
+    }
 
     _handlePluginScreen(ctx) {
       const view = Gerrit.Nav.View.PLUGIN_SCREEN;
       const plugin = ctx.params[0];
       const screen = ctx.params[1];
       this._setParams({view, plugin, screen});
-    },
+    }
 
     _handleDocumentationSearchRoute(data) {
       this._setParams({
         view: Gerrit.Nav.View.DOCUMENTATION_SEARCH,
         filter: data.params.filter || null,
       });
-    },
+    }
 
     _handleDocumentationSearchRedirectRoute(data) {
       this._redirect('/Documentation/q/filter:' +
           encodeURIComponent(data.params[0]));
-    },
+    }
 
     _handleDocumentationRedirectRoute(data) {
       if (data.params[1]) {
@@ -1481,7 +1502,7 @@
         // Redirect /Documentation to /Documentation/index.html
         this._redirect('/Documentation/index.html');
       }
-    },
+    }
 
     /**
      * Catchall route for when no other route is matched.
@@ -1494,7 +1515,7 @@
         // Route can be recognized by server, so we pass it to server.
         this._handlePassThroughRoute();
       }
-    },
+    }
 
     _show404() {
       // Note: the app's 404 display is tightly-coupled with catching 404
@@ -1502,6 +1523,8 @@
       // TODO: Decouple the gr-app error view from network responses.
       this._appElement().dispatchEvent(new CustomEvent('page-error',
           {detail: {response: {status: 404}}}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRouter.is, GrRouter);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.html b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.html
index 4bfc35b..fb7f0d6 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.html
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-router</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.html b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.html
index 0cdef8c..1b57ddb 100644
--- a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.html
+++ b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.html
@@ -29,11 +29,9 @@
       }
       gr-autocomplete {
         background-color: var(--view-background-color);
-        border: 1px solid var(--border-color);
         border-radius: var(--border-radius);
         flex: 1;
         outline: none;
-        padding: var(--spacing-xs);
       }
     </style>
     <form>
@@ -45,7 +43,6 @@
           on-commit="_handleInputCommit"
           allow-non-suggested-values
           multi
-          borderless
           threshold="[[_threshold]]"
           tab-complete
           vertical-offset="30"></gr-autocomplete>
diff --git a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.js b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.js
index 6c7b0fd..4ae1f20 100644
--- a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.js
+++ b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar.js
@@ -90,6 +90,7 @@
     'status:merged',
     'status:open',
     'status:reviewed',
+    'submissionid:',
     'topic:',
     'tr:',
   ];
@@ -102,75 +103,80 @@
 
   const TOKENIZE_REGEX = /(?:[^\s"]+|"[^"]*")+\s*/g;
 
-  Polymer({
-    is: 'gr-search-bar',
-
+  /**
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrSearchBar extends Polymer.mixinBehaviors( [
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-search-bar'; }
     /**
      * Fired when a search is committed
      *
      * @event handle-search
      */
 
-    behaviors: [
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
-
-    properties: {
-      value: {
-        type: String,
-        value: '',
-        notify: true,
-        observer: '_valueChanged',
-      },
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      query: {
-        type: Function,
-        value() {
-          return this._getSearchSuggestions.bind(this);
+    static get properties() {
+      return {
+        value: {
+          type: String,
+          value: '',
+          notify: true,
+          observer: '_valueChanged',
         },
-      },
-      projectSuggestions: {
-        type: Function,
-        value() {
-          return () => Promise.resolve([]);
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
         },
-      },
-      groupSuggestions: {
-        type: Function,
-        value() {
-          return () => Promise.resolve([]);
+        query: {
+          type: Function,
+          value() {
+            return this._getSearchSuggestions.bind(this);
+          },
         },
-      },
-      accountSuggestions: {
-        type: Function,
-        value() {
-          return () => Promise.resolve([]);
+        projectSuggestions: {
+          type: Function,
+          value() {
+            return () => Promise.resolve([]);
+          },
         },
-      },
-      _inputVal: String,
-      _threshold: {
-        type: Number,
-        value: 1,
-      },
-    },
+        groupSuggestions: {
+          type: Function,
+          value() {
+            return () => Promise.resolve([]);
+          },
+        },
+        accountSuggestions: {
+          type: Function,
+          value() {
+            return () => Promise.resolve([]);
+          },
+        },
+        _inputVal: String,
+        _threshold: {
+          type: Number,
+          value: 1,
+        },
+      };
+    }
 
     keyboardShortcuts() {
       return {
         [this.Shortcut.SEARCH]: '_handleSearch',
       };
-    },
+    }
 
     _valueChanged(value) {
       this._inputVal = value;
-    },
+    }
 
     _handleInputCommit(e) {
       this._preventDefaultAndNavigateToInputVal(e);
-    },
+    }
 
     /**
      * This function is called in a few different cases:
@@ -204,7 +210,7 @@
           detail: {inputVal: this._inputVal},
         }));
       }
-    },
+    }
 
     /**
      * Determine what array of possible suggestions should be provided
@@ -246,7 +252,7 @@
               .filter(operator => operator.includes(input))
               .map(operator => ({text: operator})));
       }
-    },
+    }
 
     /**
      * Get the sorted, pruned list of suggestions for the current search query.
@@ -289,7 +295,7 @@
                   };
                 });
           });
-    },
+    }
 
     _handleSearch(e) {
       const keyboardEvent = this.getKeyboardEvent(e);
@@ -299,6 +305,8 @@
       e.preventDefault();
       this.$.searchInput.focus();
       this.$.searchInput.selectAll();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSearchBar.is, GrSearchBar);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar_test.html b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar_test.html
index 2fe940c..c822b73 100644
--- a/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar_test.html
+++ b/polygerrit-ui/app/elements/core/gr-search-bar/gr-search-bar_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-search-bar</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -61,8 +61,8 @@
 
     getActiveElement = () => {
       return document.activeElement.shadowRoot ?
-          document.activeElement.shadowRoot.activeElement :
-          document.activeElement;
+        document.activeElement.shadowRoot.activeElement :
+        document.activeElement;
     };
 
     test('enter in search input fires event', done => {
diff --git a/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search.js b/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search.js
index 94de00c..03a2c0d 100644
--- a/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search.js
+++ b/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search.js
@@ -21,52 +21,58 @@
   const SELF_EXPRESSION = 'self';
   const ME_EXPRESSION = 'me';
 
-  Polymer({
-    is: 'gr-smart-search',
+  /**
+    * @appliesMixin Gerrit.DisplayNameMixin
+    */
+  class GrSmartSearch extends Polymer.mixinBehaviors( [
+    Gerrit.DisplayNameBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-smart-search'; }
 
-    properties: {
-      searchQuery: String,
-      _config: Object,
-      _projectSuggestions: {
-        type: Function,
-        value() {
-          return this._fetchProjects.bind(this);
+    static get properties() {
+      return {
+        searchQuery: String,
+        _config: Object,
+        _projectSuggestions: {
+          type: Function,
+          value() {
+            return this._fetchProjects.bind(this);
+          },
         },
-      },
-      _groupSuggestions: {
-        type: Function,
-        value() {
-          return this._fetchGroups.bind(this);
+        _groupSuggestions: {
+          type: Function,
+          value() {
+            return this._fetchGroups.bind(this);
+          },
         },
-      },
-      _accountSuggestions: {
-        type: Function,
-        value() {
-          return this._fetchAccounts.bind(this);
+        _accountSuggestions: {
+          type: Function,
+          value() {
+            return this._fetchAccounts.bind(this);
+          },
         },
-      },
-    },
-
-    behaviors: [
-      Gerrit.DisplayNameBehavior,
-    ],
+      };
+    }
 
     attached() {
+      super.attached();
       this.$.restAPI.getConfig().then(cfg => {
         this._config = cfg;
       });
-    },
+    }
 
     _handleSearch(e) {
       const input = e.detail.inputVal;
       if (input) {
         Gerrit.Nav.navigateToSearchQuery(input);
       }
-    },
+    }
 
     _accountOrAnon(name) {
       return this.getUserName(this._serverConfig, name, false);
-    },
+    }
 
     /**
      * Fetch from the API the predicted projects.
@@ -86,7 +92,7 @@
             const keys = Object.keys(projects);
             return keys.map(key => ({text: predicate + ':' + key}));
           });
-    },
+    }
 
     /**
      * Fetch from the API the predicted groups.
@@ -107,7 +113,7 @@
             const keys = Object.keys(groups);
             return keys.map(key => ({text: predicate + ':' + key}));
           });
-    },
+    }
 
     /**
      * Fetch from the API the predicted accounts.
@@ -138,15 +144,17 @@
               return accounts;
             }
           });
-    },
+    }
 
     _mapAccountsHelper(accounts, predicate) {
       return accounts.map(account => ({
         label: account.name || '',
         text: account.email ?
-            `${predicate}:${account.email}` :
-            `${predicate}:"${this._accountOrAnon(account)}"`,
+          `${predicate}:${account.email}` :
+          `${predicate}:"${this._accountOrAnon(account)}"`,
       }));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSmartSearch.is, GrSmartSearch);
 })();
diff --git a/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search_test.html b/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search_test.html
index a70eb7c..5a4e341 100644
--- a/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search_test.html
+++ b/polygerrit-ui/app/elements/core/gr-smart-search/gr-smart-search_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-smart-search</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -48,7 +48,6 @@
       sandbox.restore();
     });
 
-
     test('Autocompletes accounts', () => {
       sandbox.stub(element.$.restAPI, 'getSuggestedAccounts', () =>
         Promise.resolve([
diff --git a/polygerrit-ui/app/elements/custom-dark-theme_test.html b/polygerrit-ui/app/elements/custom-dark-theme_test.html
index 4cf35f1..1cd042a 100644
--- a/polygerrit-ui/app/elements/custom-dark-theme_test.html
+++ b/polygerrit-ui/app/elements/custom-dark-theme_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-app-it_test</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/custom-light-theme_test.html b/polygerrit-ui/app/elements/custom-light-theme_test.html
index e346af5..0cabd09 100644
--- a/polygerrit-ui/app/elements/custom-light-theme_test.html
+++ b/polygerrit-ui/app/elements/custom-light-theme_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-app-it_test</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api-mock.js b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api-mock.js
index b7994e6..4009420 100644
--- a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api-mock.js
+++ b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api-mock.js
@@ -17,16 +17,20 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'comment-api-mock',
+  class CommentApiMock extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'comment-api-mock'; }
 
-    properties: {
-      _changeComments: Object,
-    },
+    static get properties() {
+      return {
+        _changeComments: Object,
+      };
+    }
 
     loadComments() {
       return this._reloadComments();
-    },
+    }
 
     /**
      * For the purposes of the mock, _reloadDrafts is not included because its
@@ -38,13 +42,15 @@
       return this._reloadComments().then(() => {
         return e.detail.resolve();
       });
-    },
+    }
 
     _reloadComments() {
       return this.$.commentAPI.loadAll(this._changeNum)
           .then(comments => {
             this._changeComments = this.$.commentAPI._changeComments;
           });
-    },
-  });
+    }
+  }
+
+  customElements.define(CommentApiMock.is, CommentApiMock);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api.js b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api.js
index efed78d..e84e996 100644
--- a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api.js
+++ b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api.js
@@ -248,9 +248,9 @@
     const all = comments.concat(drafts).concat(robotComments);
 
     const baseComments = all.filter(c =>
-        this._isInBaseOfPatchRange(c, patchRange));
+      this._isInBaseOfPatchRange(c, patchRange));
     const revisionComments = all.filter(c =>
-        this._isInRevisionOfPatchRange(c, patchRange));
+      this._isInRevisionOfPatchRange(c, patchRange));
 
     return {
       meta: {
@@ -348,7 +348,7 @@
     const threads = this.getCommentThreads(this._sortComments(comments));
 
     const unresolvedThreads = threads
-      .filter(thread =>
+        .filter(thread =>
           thread.comments.length &&
           thread.comments[thread.comments.length - 1].unresolved);
 
@@ -460,20 +460,27 @@
         this._isInRevisionOfPatchRange(comment, range);
   };
 
-  Polymer({
-    is: 'gr-comment-api',
+  /**
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  class GrCommentApi extends Polymer.mixinBehaviors( [
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-comment-api'; }
 
-    properties: {
-      _changeComments: Object,
-    },
+    static get properties() {
+      return {
+        _changeComments: Object,
+      };
+    }
 
-    listeners: {
-      'reload-drafts': 'reloadDrafts',
-    },
-
-    behaviors: [
-      Gerrit.PatchSetBehavior,
-    ],
+    created() {
+      super.created();
+      this.addEventListener('reload-drafts',
+          changeNum => this.reloadDrafts(changeNum));
+    }
 
     /**
      * Load all comments (with drafts and robot comments) for the given change
@@ -491,10 +498,10 @@
 
       return Promise.all(promises).then(([comments, robotComments, drafts]) => {
         this._changeComments = new ChangeComments(comments,
-          robotComments, drafts, changeNum);
+            robotComments, drafts, changeNum);
         return this._changeComments;
       });
-    },
+    }
 
     /**
      * Re-initialize _changeComments with a new ChangeComments object, that
@@ -513,6 +520,8 @@
             this._changeComments.robotComments, drafts, changeNum);
         return this._changeComments;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCommentApi.is, GrCommentApi);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api_test.html b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api_test.html
index c44e8c4..4261c2d 100644
--- a/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-comment-api/gr-comment-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-comment-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -109,7 +109,7 @@
       let draftStub;
       setup(() => {
         commentStub = sandbox.stub(element.$.restAPI, 'getDiffComments')
-          .returns(Promise.resolve({}));
+            .returns(Promise.resolve({}));
         robotCommentStub = sandbox.stub(element.$.restAPI,
             'getDiffRobotComments').returns(Promise.resolve({}));
         draftStub = sandbox.stub(element.$.restAPI, 'getDiffDrafts')
diff --git a/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer.js b/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer.js
index 3d9c172..d1df4d0 100644
--- a/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer.js
+++ b/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer.js
@@ -24,20 +24,23 @@
     [Gerrit.CoverageType.NOT_INSTRUMENTED, 'Not instrumented by any tests.'],
   ]);
 
-  Polymer({
-    is: 'gr-coverage-layer',
+  class GrCoverageLayer extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-coverage-layer'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * Must be sorted by code_range.start_line.
        * Must only contain ranges that match the side.
        *
        * @type {!Array<!Gerrit.CoverageRange>}
        */
-      coverageRanges: Array,
-      side: String,
+        coverageRanges: Array,
+        side: String,
 
-      /**
+        /**
        * We keep track of the line number from the previous annotate() call,
        * and also of the index of the coverage range that had matched.
        * annotate() calls are coming in with increasing line numbers and
@@ -45,15 +48,16 @@
        * and efficient way for finding the coverage range that matches a given
        * line number.
        */
-      _lineNumber: {
-        type: Number,
-        value: 0,
-      },
-      _index: {
-        type: Number,
-        value: 0,
-      },
-    },
+        _lineNumber: {
+          type: Number,
+          value: 0,
+        },
+        _index: {
+          type: Number,
+          value: 0,
+        },
+      };
+    }
 
     /**
      * Layer method to add annotations to a line.
@@ -102,6 +106,8 @@
         lineNumberEl.title = TOOLTIP_MAP.get(coverageRange.type);
         return;
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCoverageLayer.is, GrCoverageLayer);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer_test.html b/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer_test.html
index 45a67e1..99c583d 100644
--- a/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-coverage-layer/gr-coverage-layer_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-coverage-layer</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified.js b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified.js
index 0a51d92..144cc56 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified.js
@@ -105,7 +105,7 @@
     let tr = content.parentElement.parentElement;
     while (tr = tr.nextSibling) {
       if (tr.classList.contains('both') || (
-          (side === 'left' && tr.classList.contains('remove')) ||
+        (side === 'left' && tr.classList.contains('remove')) ||
           (side === 'right' && tr.classList.contains('add')))) {
         return tr.querySelector('.contentText');
       }
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified_test.html b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified_test.html
index 19e017d..4c44414 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder-unified_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>GrDiffBuilderUnified</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
index 69c2419..2a57162 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.html
@@ -219,8 +219,8 @@
         getLineNumberByChild(node) {
           const lineEl = this.getLineElByChild(node);
           return lineEl ?
-              parseInt(lineEl.getAttribute('data-value'), 10) :
-              null;
+            parseInt(lineEl.getAttribute('data-value'), 10) :
+            null;
         },
 
         getContentByLine(lineNumber, opt_side, opt_root) {
@@ -249,7 +249,7 @@
 
         getSideByLineEl(lineEl) {
           return lineEl.classList.contains(GrDiffBuilder.Side.RIGHT) ?
-          GrDiffBuilder.Side.RIGHT : GrDiffBuilder.Side.LEFT;
+            GrDiffBuilder.Side.RIGHT : GrDiffBuilder.Side.LEFT;
         },
 
         emitGroup(group, sectionEl) {
@@ -304,7 +304,7 @@
           let builder = null;
           if (this.isImageDiff) {
             builder = new GrDiffBuilderImage(diff, prefs, this.diffElement,
-              this.baseImage, this.revisionImage);
+                this.baseImage, this.revisionImage);
           } else if (diff.binary) {
             // If the diff is binary, but not an image.
             return new GrDiffBuilderBinary(diff, prefs, this.diffElement);
@@ -352,8 +352,8 @@
 
                 // If endIndex isn't present, continue to the end of the line.
                 const endIndex = highlight.endIndex === undefined ?
-                    line.text.length :
-                    highlight.endIndex;
+                  line.text.length :
+                  highlight.endIndex;
 
                 GrAnnotation.annotateElement(
                     contentEl,
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.js b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.js
index c25e90c..5eb8b09 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder.js
@@ -183,7 +183,7 @@
           continue;
         }
         const lineNumber = opt_side === 'left' ?
-            line.beforeNumber : line.afterNumber;
+          line.beforeNumber : line.afterNumber;
         if (lineNumber < start || lineNumber > end) { continue; }
 
         if (out_lines) { out_lines.push(line); }
@@ -292,6 +292,7 @@
       e.detail = {
         groups,
         section,
+        numLines,
       };
       // Let it bubble up the DOM tree.
     });
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
index 3fdf242..758798a 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-builder/gr-diff-builder_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-builder</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -171,7 +171,6 @@
           '👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍');
     });
 
-
     test('line_length ignored if line_wrapping is true', () => {
       builder._prefs = {line_wrapping: true, tab_size: 4, line_length: 50};
       const text = 'a'.repeat(51);
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.js b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.js
index a53b86e..039a99fa 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor.js
@@ -35,33 +35,36 @@
   const LEFT_SIDE_CLASS = 'target-side-left';
   const RIGHT_SIDE_CLASS = 'target-side-right';
 
-  Polymer({
-    is: 'gr-diff-cursor',
+  class GrDiffCursor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-diff-cursor'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * Either DiffSides.LEFT or DiffSides.RIGHT.
        */
-      side: {
-        type: String,
-        value: DiffSides.RIGHT,
-      },
-      /** @type {!HTMLElement|undefined} */
-      diffRow: {
-        type: Object,
-        notify: true,
-        observer: '_rowChanged',
-      },
+        side: {
+          type: String,
+          value: DiffSides.RIGHT,
+        },
+        /** @type {!HTMLElement|undefined} */
+        diffRow: {
+          type: Object,
+          notify: true,
+          observer: '_rowChanged',
+        },
 
-      /**
+        /**
        * The diff views to cursor through and listen to.
        */
-      diffs: {
-        type: Array,
-        value() { return []; },
-      },
+        diffs: {
+          type: Array,
+          value() { return []; },
+        },
 
-      /**
+        /**
        * If set, the cursor will attempt to move to the line number (instead of
        * the first chunk) the next time the diff renders. It is set back to null
        * when used. It should be only used if you want the line to be focused
@@ -71,56 +74,61 @@
        *
        * @type (?number)
        */
-      initialLineNumber: {
-        type: Number,
-        value: null,
-      },
+        initialLineNumber: {
+          type: Number,
+          value: null,
+        },
 
-      /**
+        /**
        * The scroll behavior for the cursor. Values are 'never' and
        * 'keep-visible'. 'keep-visible' will only scroll if the cursor is beyond
        * the viewport.
        */
-      _scrollBehavior: {
-        type: String,
-        value: ScrollBehavior.KEEP_VISIBLE,
-      },
+        _scrollBehavior: {
+          type: String,
+          value: ScrollBehavior.KEEP_VISIBLE,
+        },
 
-      _focusOnMove: {
-        type: Boolean,
-        value: true,
-      },
+        _focusOnMove: {
+          type: Boolean,
+          value: true,
+        },
 
-      _listeningForScroll: Boolean,
-    },
+        _listeningForScroll: Boolean,
+      };
+    }
 
-    observers: [
-      '_updateSideClass(side)',
-      '_diffsChanged(diffs.splices)',
-    ],
+    static get observers() {
+      return [
+        '_updateSideClass(side)',
+        '_diffsChanged(diffs.splices)',
+      ];
+    }
 
     attached() {
+      super.attached();
       // Catch when users are scrolling as the view loads.
       this.listen(window, 'scroll', '_handleWindowScroll');
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'scroll', '_handleWindowScroll');
-    },
+    }
 
     moveLeft() {
       this.side = DiffSides.LEFT;
       if (this._isTargetBlank()) {
         this.moveUp();
       }
-    },
+    }
 
     moveRight() {
       this.side = DiffSides.RIGHT;
       if (this._isTargetBlank()) {
         this.moveUp();
       }
-    },
+    }
 
     moveDown() {
       if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE) {
@@ -128,7 +136,7 @@
       } else {
         this.$.cursorManager.next();
       }
-    },
+    }
 
     moveUp() {
       if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE) {
@@ -136,7 +144,7 @@
       } else {
         this.$.cursorManager.previous();
       }
-    },
+    }
 
     moveToNextChunk(opt_clipToTop) {
       this.$.cursorManager.next(this._isFirstRowOfChunk.bind(this),
@@ -144,22 +152,22 @@
             return target.parentNode.scrollHeight;
           }, opt_clipToTop);
       this._fixSide();
-    },
+    }
 
     moveToPreviousChunk() {
       this.$.cursorManager.previous(this._isFirstRowOfChunk.bind(this));
       this._fixSide();
-    },
+    }
 
     moveToNextCommentThread() {
       this.$.cursorManager.next(this._rowHasThread.bind(this));
       this._fixSide();
-    },
+    }
 
     moveToPreviousCommentThread() {
       this.$.cursorManager.previous(this._rowHasThread.bind(this));
       this._fixSide();
-    },
+    }
 
     /**
      * @param {number} number
@@ -172,7 +180,7 @@
         this.side = side;
         this.$.cursorManager.setCursor(row);
       }
-    },
+    }
 
     /**
      * Get the line number element targeted by the cursor row and side.
@@ -190,24 +198,24 @@
       }
 
       return this.diffRow.querySelector(lineElSelector);
-    },
+    }
 
     getTargetDiffElement() {
       if (!this.diffRow) return null;
 
       const hostOwner = Polymer.dom(/** @type {Node} */ (this.diffRow))
-        .getOwnerRoot();
+          .getOwnerRoot();
       if (hostOwner && hostOwner.host &&
           hostOwner.host.tagName === 'GR-DIFF') {
         return hostOwner.host;
       }
       return null;
-    },
+    }
 
     moveToFirstChunk() {
       this.$.cursorManager.moveToStart();
       this.moveToNextChunk(true);
-    },
+    }
 
     reInitCursor() {
       this._updateStops();
@@ -217,7 +225,7 @@
       } else {
         this.moveToFirstChunk();
       }
-    },
+    }
 
     _handleWindowScroll() {
       if (this._listeningForScroll) {
@@ -225,26 +233,40 @@
         this._focusOnMove = false;
         this._listeningForScroll = false;
       }
-    },
+    }
 
     handleDiffUpdate() {
       this._updateStops();
       if (!this.diffRow) {
         // does not scroll during init unless requested
         const scrollingBehaviorForInit = this.initialLineNumber ?
-            ScrollBehavior.KEEP_VISIBLE :
-            ScrollBehavior.NEVER;
+          ScrollBehavior.KEEP_VISIBLE :
+          ScrollBehavior.NEVER;
         this._scrollBehavior = scrollingBehaviorForInit;
         this.reInitCursor();
       }
       this._scrollBehavior = ScrollBehavior.KEEP_VISIBLE;
       this._focusOnMove = true;
       this._listeningForScroll = false;
-    },
+    }
 
     _handleDiffRenderStart() {
       this._listeningForScroll = true;
-    },
+    }
+
+    createCommentInPlace() {
+      const diffWithRangeSelected = this.diffs.find(diff => {
+        return diff.isRangeSelected();
+      });
+      if (diffWithRangeSelected) {
+        diffWithRangeSelected.createRangeComment();
+      } else {
+        const line = this.getTargetLineElement();
+        if (line) {
+          this.getTargetDiffElement().addDraftAtLine(line);
+        }
+      }
+    }
 
     /**
      * Get an object describing the location of the cursor. Such as
@@ -276,7 +298,7 @@
         leftSide: cell.matches('.left'),
         number: parseInt(number, 10),
       };
-    },
+    }
 
     _getViewMode() {
       if (!this.diffRow) {
@@ -288,24 +310,24 @@
       } else {
         return DiffViewMode.UNIFIED;
       }
-    },
+    }
 
     _rowHasSide(row) {
       const selector = (this.side === DiffSides.LEFT ? '.left' : '.right') +
           ' + .content';
       return !!row.querySelector(selector);
-    },
+    }
 
     _isFirstRowOfChunk(row) {
       const parentClassList = row.parentNode.classList;
       return parentClassList.contains('section') &&
           parentClassList.contains('delta') &&
           !row.previousSibling;
-    },
+    }
 
     _rowHasThread(row) {
       return row.querySelector('.thread-group');
-    },
+    }
 
     /**
      * If we jumped to a row where there is no content on the current side then
@@ -315,9 +337,9 @@
       if (this._getViewMode() === DiffViewMode.SIDE_BY_SIDE &&
           this._isTargetBlank()) {
         this.side = this.side === DiffSides.LEFT ?
-            DiffSides.RIGHT : DiffSides.LEFT;
+          DiffSides.RIGHT : DiffSides.LEFT;
       }
-    },
+    }
 
     _isTargetBlank() {
       if (!this.diffRow) {
@@ -327,14 +349,14 @@
       const actions = this._getActionsForRow();
       return (this.side === DiffSides.LEFT && !actions.left) ||
           (this.side === DiffSides.RIGHT && !actions.right);
-    },
+    }
 
     _rowChanged(newRow, oldRow) {
       if (oldRow) {
         oldRow.classList.remove(LEFT_SIDE_CLASS, RIGHT_SIDE_CLASS);
       }
       this._updateSideClass();
-    },
+    }
 
     _updateSideClass() {
       if (!this.diffRow) {
@@ -344,11 +366,11 @@
           this.diffRow);
       this.toggleClass(RIGHT_SIDE_CLASS, this.side === DiffSides.RIGHT,
           this.diffRow);
-    },
+    }
 
     _isActionType(type) {
       return type !== 'blank' && type !== 'contextControl';
-    },
+    }
 
     _getActionsForRow() {
       const actions = {left: false, right: false};
@@ -359,18 +381,18 @@
             this.diffRow.getAttribute('right-type'));
       }
       return actions;
-    },
+    }
 
     _getStops() {
       return this.diffs.reduce(
           (stops, diff) => {
             return stops.concat(diff.getCursorStops());
           }, []);
-    },
+    }
 
     _updateStops() {
       this.$.cursorManager.stops = this._getStops();
-    },
+    }
 
     /**
      * Setup and tear down on-render listeners for any diffs that are added or
@@ -391,22 +413,22 @@
         splice = changeRecord.indexSplices[spliceIdx];
 
         for (i = splice.index;
-            i < splice.index + splice.addedCount;
-            i++) {
+          i < splice.index + splice.addedCount;
+          i++) {
           this.listen(this.diffs[i], 'render-start', '_handleDiffRenderStart');
           this.listen(this.diffs[i], 'render-content', 'handleDiffUpdate');
         }
 
         for (i = 0;
-            i < splice.removed && splice.removed.length;
-            i++) {
+          i < splice.removed && splice.removed.length;
+          i++) {
           this.unlisten(splice.removed[i],
               'render-start', '_handleDiffRenderStart');
           this.unlisten(splice.removed[i],
               'render-content', 'handleDiffUpdate');
         }
       }
-    },
+    }
 
     _findRowByNumberAndFile(targetNumber, side, opt_path) {
       let stops;
@@ -423,6 +445,8 @@
           return stops[i];
         }
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffCursor.is, GrDiffCursor);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor_test.html b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor_test.html
index 1c1100d..626ab33 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-cursor/gr-diff-cursor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-cursor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -259,6 +259,70 @@
       );
     });
 
+    suite('createCommentInPlace', () => {
+      setup(() => {
+        diffElement.loggedIn = true;
+      });
+
+      test('adds new draft for selected line on the left', done => {
+        cursorElement.moveToLineNumber(2, 'left');
+        diffElement.addEventListener('create-comment', e => {
+          const {lineNum, range, side, patchNum} = e.detail;
+          assert.equal(lineNum, 2);
+          assert.equal(range, undefined);
+          assert.equal(patchNum, 1);
+          assert.equal(side, 'left');
+          done();
+        });
+        cursorElement.createCommentInPlace();
+      });
+
+      test('adds draft for selected line on the right', done => {
+        cursorElement.moveToLineNumber(4, 'right');
+        diffElement.addEventListener('create-comment', e => {
+          const {lineNum, range, side, patchNum} = e.detail;
+          assert.equal(lineNum, 4);
+          assert.equal(range, undefined);
+          assert.equal(patchNum, 2);
+          assert.equal(side, 'right');
+          done();
+        });
+        cursorElement.createCommentInPlace();
+      });
+
+      test('createCommentInPlace creates comment for range if selected', done => {
+        const someRange = {
+          start_line: 2,
+          start_character: 3,
+          end_line: 6,
+          end_character: 1,
+        };
+        diffElement.$.highlights.selectedRange = {
+          side: 'right',
+          range: someRange,
+        };
+        diffElement.addEventListener('create-comment', e => {
+          const {lineNum, range, side, patchNum} = e.detail;
+          assert.equal(lineNum, 6);
+          assert.equal(range, someRange);
+          assert.equal(patchNum, 2);
+          assert.equal(side, 'right');
+          done();
+        });
+        cursorElement.createCommentInPlace();
+      });
+
+      test('createCommentInPlace ignores call if nothing is selected', () => {
+        const createRangeCommentStub = sandbox.stub(diffElement,
+            'createRangeComment');
+        const addDraftAtLineStub = sandbox.stub(diffElement, 'addDraftAtLine');
+        cursorElement.diffRow = undefined;
+        cursorElement.createCommentInPlace();
+        assert.isFalse(createRangeCommentStub.called);
+        assert.isFalse(addDraftAtLineStub.called);
+      });
+    });
+
     test('getAddress', () => {
       // It should initialize to the first chunk: line 5 of the revision.
       assert.deepEqual(cursorElement.getAddress(),
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation.js b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation.js
index c1d53aa..c729bcb 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation.js
@@ -43,6 +43,65 @@
     },
 
     /**
+     * Annotates the [offset, offset+length) text segment in the parent with the
+     * element definition provided as arguments.
+     *
+     * @param {!Element} parent the node whose contents will be annotated.
+     * @param {number} offset the 0-based offset from which the annotation will
+     *   start.
+     * @param {number} length of the annotated text.
+     * @param {GrAnnotation.ElementSpec} elementSpec the spec to create the
+     *   annotating element.
+     */
+    annotateWithElement(parent, offset, length, {tagName, attributes = {}}) {
+      let childNodes;
+
+      if (parent instanceof Element) {
+        childNodes = Array.from(parent.childNodes);
+      } else if (parent instanceof Text) {
+        childNodes = [parent];
+        parent = parent.parentNode;
+      } else {
+        return;
+      }
+
+      const nestedNodes = [];
+      for (let node of childNodes) {
+        const initialNodeLength = this.getLength(node);
+        // If the current node is completely before the offset.
+        if (offset > 0 && initialNodeLength <= offset) {
+          offset -= initialNodeLength;
+          continue;
+        }
+
+        if (offset > 0) {
+          node = this.splitNode(node, offset);
+          offset = 0;
+        }
+        if (this.getLength(node) > length) {
+          this.splitNode(node, length);
+        }
+        nestedNodes.push(node);
+
+        length -= this.getLength(node);
+        if (!length) break;
+      }
+
+      const wrapper = document.createElement(tagName);
+      const sanitizer = window.Polymer.sanitizeDOMValue;
+      for (const [name, value] of Object.entries(attributes)) {
+        wrapper.setAttribute(
+            name, sanitizer
+              ? sanitizer(value, name, 'attribute', wrapper)
+              : value);
+      }
+      for (const inner of nestedNodes) {
+        parent.replaceChild(wrapper, inner);
+        wrapper.appendChild(inner);
+      }
+    },
+
+    /**
      * Surrounds the element's text at specified range in an ANNOTATION_TAG
      * element. If the element has child elements, the range is split and
      * applied as deeply as possible.
@@ -210,5 +269,15 @@
     },
   };
 
+  /**
+   * Data used to construct an element.
+   *
+   * @typedef {{
+   *   tagName: string,
+   *   attributes: (!Object<string, *>|undefined)
+   * }}
+   */
+  GrAnnotation.ElementSpec;
+
   window.GrAnnotation = GrAnnotation;
 })(window);
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation_test.html b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation_test.html
index 86d5e45..a2c271b 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-annotation_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-annotation</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -40,13 +40,19 @@
     let str;
     let parent;
     let textNode;
+    let sandbox;
 
     setup(() => {
+      sandbox = sinon.sandbox.create();
       parent = fixture('basic');
       textNode = parent.childNodes[0];
       str = textNode.textContent;
     });
 
+    teardown(() => {
+      sandbox.restore();
+    });
+
     test('_annotateText Case 1', () => {
       GrAnnotation._annotateText(textNode, 0, str.length, 'foobar');
 
@@ -168,7 +174,7 @@
       assert.equal(layer4[0].textContent +
           layer4[1].textContent +
           layer4[2].textContent,
-          layers[3]);
+      layers[3]);
     });
 
     test('splitTextNode', () => {
@@ -191,5 +197,95 @@
       assert(node.textContent, helloString);
       assert(tail.textContent, unicodeString);
     });
+
+    suite('annotateWithElement', () => {
+      const fullText = '01234567890123456789';
+      let mockSanitize;
+
+      setup(() => {
+        mockSanitize = sandbox.spy(window.Polymer, 'sanitizeDOMValue');
+      });
+
+      test('annotates when fully contained', () => {
+        const length = 10;
+        const container = document.createElement('div');
+        container.textContent = fullText;
+        GrAnnotation.annotateWithElement(
+            container, 1, length, {tagName: 'test-wrapper'});
+
+        assert.equal(
+            container.innerHTML,
+            '0<test-wrapper>1234567890</test-wrapper>123456789');
+      });
+
+      test('annotates when spanning multiple nodes', () => {
+        const length = 10;
+        const container = document.createElement('div');
+        container.textContent = fullText;
+        GrAnnotation.annotateElement(container, 5, length, 'testclass');
+        GrAnnotation.annotateWithElement(
+            container, 1, length, {tagName: 'test-wrapper'});
+
+        assert.equal(
+            container.innerHTML,
+            '0'
+              + '<test-wrapper>'
+              + '1234'
+              + '<hl class="testclass">567890</hl>'
+              + '</test-wrapper>'
+              + '<hl class="testclass">1234</hl>'
+              + '56789');
+      });
+
+      test('annotates text node', () => {
+        const length = 10;
+        const container = document.createElement('div');
+        container.textContent = fullText;
+        GrAnnotation.annotateWithElement(
+            container.childNodes[0], 1, length, {tagName: 'test-wrapper'});
+
+        assert.equal(
+            container.innerHTML,
+            '0<test-wrapper>1234567890</test-wrapper>123456789');
+      });
+
+      test('handles zero-length nodes', () => {
+        const container = document.createElement('div');
+        container.appendChild(document.createTextNode('0123456789'));
+        container.appendChild(document.createElement('span'));
+        container.appendChild(document.createTextNode('0123456789'));
+        GrAnnotation.annotateWithElement(
+            container, 1, 10, {tagName: 'test-wrapper'});
+
+        assert.equal(
+            container.innerHTML,
+            '0<test-wrapper>123456789<span></span>0</test-wrapper>123456789');
+      });
+
+      test('sets sanitized attributes', () => {
+        const container = document.createElement('div');
+        container.textContent = fullText;
+        const attributes = {
+          'href': 'foo',
+          'data-foo': 'bar',
+          'class': 'hello world',
+        };
+        GrAnnotation.annotateWithElement(
+            container, 1, length, {tagName: 'test-wrapper', attributes});
+        assert(mockSanitize.calledWith(
+            'foo', 'href', 'attribute', sinon.match.instanceOf(Element)));
+        assert(mockSanitize.calledWith(
+            'bar', 'data-foo', 'attribute', sinon.match.instanceOf(Element)));
+        assert(mockSanitize.calledWith(
+            'hello world',
+            'class',
+            'attribute',
+            sinon.match.instanceOf(Element)));
+        const el = container.querySelector('test-wrapper');
+        assert.equal(el.getAttribute('href'), 'foo');
+        assert.equal(el.getAttribute('data-foo'), 'bar');
+        assert.equal(el.getAttribute('class'), 'hello world');
+      });
+    });
   });
 </script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
index 5472489..88d19aa 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight.js
@@ -17,33 +17,55 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-diff-highlight',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrDiffHighlight extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff-highlight'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {!Array<!Gerrit.HoveredRange>} */
-      commentRanges: {
-        type: Array,
-        notify: true,
-      },
-      loggedIn: Boolean,
-      /**
+        commentRanges: {
+          type: Array,
+          notify: true,
+        },
+        loggedIn: Boolean,
+        /**
        * querySelector can return null, so needs to be nullable.
        *
        * @type {?HTMLElement}
        * */
-      _cachedDiffBuilder: Object,
-    },
+        _cachedDiffBuilder: Object,
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+        /**
+       * Which range is currently selected by the user.
+       * Stored in order to add a range-based comment
+       * later.
+       * undefined if no range is selected.
+       *
+       * @type {{side: string, range: Gerrit.Range}|undefined}
+       */
+        selectedRange: {
+          type: Object,
+          notify: true,
+        },
+      };
+    }
 
-    listeners: {
-      'comment-thread-mouseleave': '_handleCommentThreadMouseleave',
-      'comment-thread-mouseenter': '_handleCommentThreadMouseenter',
-      'create-range-comment': '_createRangeComment',
-    },
+    created() {
+      super.created();
+      this.addEventListener('comment-thread-mouseleave',
+          e => this._handleCommentThreadMouseleave(e));
+      this.addEventListener('comment-thread-mouseenter',
+          e => this._handleCommentThreadMouseenter(e));
+      this.addEventListener('create-comment-requested',
+          e => this._handleRangeCommentRequest(e));
+    }
 
     get diffBuilder() {
       if (!this._cachedDiffBuilder) {
@@ -51,12 +73,7 @@
             Polymer.dom(this).querySelector('gr-diff-builder');
       }
       return this._cachedDiffBuilder;
-    },
-
-
-    isRangeSelected() {
-      return !!this.$$('gr-selection-action-box');
-    },
+    }
 
     /**
      * Determines side/line/range for a DOM selection and shows a tooltip.
@@ -85,7 +102,7 @@
       this.debounce(
           'selectionChange', () => this._handleSelection(selection, isMouseUp),
           10);
-    },
+    }
 
     _getThreadEl(e) {
       const path = Polymer.dom(e).path || [];
@@ -93,7 +110,7 @@
         if (pathEl.classList.contains('comment-thread')) return pathEl;
       }
       return null;
-    },
+    }
 
     _handleCommentThreadMouseenter(e) {
       const threadEl = this._getThreadEl(e);
@@ -102,7 +119,7 @@
       if (index !== undefined) {
         this.set(['commentRanges', index, 'hovering'], true);
       }
-    },
+    }
 
     _handleCommentThreadMouseleave(e) {
       const threadEl = this._getThreadEl(e);
@@ -111,7 +128,7 @@
       if (index !== undefined) {
         this.set(['commentRanges', index, 'hovering'], false);
       }
-    },
+    }
 
     _indexForThreadEl(threadEl) {
       const side = threadEl.getAttribute('comment-side');
@@ -120,7 +137,7 @@
       if (!range) return undefined;
 
       return this._indexOfCommentRange(side, range);
-    },
+    }
 
     _indexOfCommentRange(side, range) {
       function rangesEqual(a, b) {
@@ -137,8 +154,8 @@
       }
 
       return this.commentRanges.findIndex(commentRange =>
-          commentRange.side === side && rangesEqual(commentRange.range, range));
-    },
+        commentRange.side === side && rangesEqual(commentRange.range, range));
+    }
 
     /**
      * Get current normalized selection.
@@ -176,7 +193,7 @@
           end: endRange.end,
         };
       }
-    },
+    }
 
     /**
      * Normalize a specific DOM Range.
@@ -190,7 +207,7 @@
         end: this._normalizeSelectionSide(
             range.endContainer, range.endOffset),
       }, domRange);
-    },
+    }
 
     /**
      * Adjust triple click selection for the whole line.
@@ -231,7 +248,7 @@
         };
       }
       return range;
-    },
+    }
 
     /**
      * Convert DOM Range selection to concrete numbers (line, column, side).
@@ -288,7 +305,7 @@
         line,
         column,
       };
-    },
+    }
 
     /**
      * The only line in which add a comment tooltip is cut off is the first
@@ -304,7 +321,7 @@
       }
       actionBox.positionBelow = true;
       actionBox.placeBelow(range);
-    },
+    }
 
     _isRangeValid(range) {
       if (!range || !range.start || !range.end) {
@@ -318,7 +335,7 @@
         return false;
       }
       return true;
-    },
+    }
 
     _handleSelection(selection, isMouseUp) {
       const normalizedRange = this._getNormalizedRange(selection);
@@ -351,12 +368,12 @@
         // is empty to see that it's at the end of a line.
         const content = domRange.cloneContents().querySelector('.contentText');
         if (isMouseUp && this._getLength(content) === 0) {
-          this.fire('create-range-comment', {side: start.side, range: {
+          this._fireCreateRangeComment(start.side, {
             start_line: start.line,
             start_character: 0,
             end_line: start.line,
             end_character: start.column,
-          }});
+          });
         }
         return;
       }
@@ -367,13 +384,15 @@
         const root = Polymer.dom(this.root);
         root.insertBefore(actionBox, root.firstElementChild);
       }
-      actionBox.range = {
-        start_line: start.line,
-        start_character: start.column,
-        end_line: end.line,
-        end_character: end.column,
+      this.selectedRange = {
+        range: {
+          start_line: start.line,
+          start_character: start.column,
+          end_line: end.line,
+          end_character: end.column,
+        },
+        side: start.side,
       };
-      actionBox.side = start.side;
       if (start.line === end.line) {
         this._positionActionBox(actionBox, start.line, domRange);
       } else if (start.node instanceof Text) {
@@ -388,18 +407,29 @@
       } else {
         this._positionActionBox(actionBox, start.line, start.node);
       }
-    },
+    }
 
-    _createRangeComment(e) {
+    _fireCreateRangeComment(side, range) {
+      this.fire('create-range-comment', {side, range});
       this._removeActionBox();
-    },
+    }
+
+    _handleRangeCommentRequest(e) {
+      e.stopPropagation();
+      if (!this.selectedRange) {
+        throw Error('Selected Range is needed for new range comment!');
+      }
+      const {side, range} = this.selectedRange;
+      this._fireCreateRangeComment(side, range);
+    }
 
     _removeActionBox() {
+      this.selectedRange = undefined;
       const actionBox = this.$$('gr-selection-action-box');
       if (actionBox) {
         Polymer.dom(this.root).removeChild(actionBox);
       }
-    },
+    }
 
     _convertOffsetToColumn(el, offset) {
       if (el instanceof Element && el.classList.contains('content')) {
@@ -415,7 +445,7 @@
         }
       }
       return offset;
-    },
+    }
 
     /**
      * Traverse Element from right to left, call callback for each node.
@@ -440,7 +470,7 @@
         }
         node = nextNode;
       }
-    },
+    }
 
     /**
      * Get length of a node. If the node is a content node, then only give the
@@ -455,6 +485,8 @@
       } else {
         return GrAnnotation.getLength(node);
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffHighlight.is, GrDiffHighlight);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
index 7ca5f5e..3de521d 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-highlight/gr-diff-highlight_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-highlight</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -228,13 +228,25 @@
         assert.isFalse(element.set.called);
       });
 
-      test('on create-range-comment action box is removed', () => {
+      test(`create-range-comment for range when create-comment-requested
+            is fired`, () => {
         sandbox.stub(element, '_removeActionBox');
-        element.fire('create-range-comment', {
-          comment: {
-            range: {},
+        element.selectedRange = {
+          side: 'left',
+          range: {
+            start_line: 7,
+            start_character: 11,
+            end_line: 24,
+            end_character: 42,
           },
+        };
+        const requestEvent = new CustomEvent('create-comment-requested');
+        let createRangeEvent;
+        element.addEventListener('create-range-comment', e => {
+          createRangeEvent = e;
         });
+        element.dispatchEvent(requestEvent);
+        assert.deepEqual(element.selectedRange, createRangeEvent.detail);
         assert.isTrue(element._removeActionBox.called);
       });
     });
@@ -271,14 +283,6 @@
         element._handleSelection(selection);
       };
 
-      const getActionRange = () =>
-          Polymer.dom(element.root).querySelector(
-              'gr-selection-action-box').range;
-
-      const getActionSide = () =>
-          Polymer.dom(element.root).querySelector(
-              'gr-selection-action-box').side;
-
       const getLineElByChild = node => {
         const stubs = contentStubs.find(stub => stub.contentTd.contains(node));
         return stubs && stubs.lineEl;
@@ -329,14 +333,14 @@
         sandbox.spy(element, '_positionActionBox');
         emulateSelection(content.firstChild, 5, content.firstChild, 12);
         const actionBox = element.$$('gr-selection-action-box');
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 138,
           start_character: 5,
           end_line: 138,
           end_character: 12,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
         assert.notOk(actionBox.positionBelow);
       });
 
@@ -346,16 +350,15 @@
         sandbox.spy(element, '_positionActionBox');
         emulateSelection(
             startContent.firstChild, 10, endContent.lastChild, 7);
-        assert.isTrue(element.isRangeSelected());
         const actionBox = element.$$('gr-selection-action-box');
-
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 119,
           start_character: 10,
           end_line: 120,
           end_character: 36,
         });
-        assert.equal(getActionSide(), 'right');
+        assert.equal(side, 'right');
         assert.notOk(actionBox.positionBelow);
       });
 
@@ -381,8 +384,8 @@
           removeAllRanges: sandbox.stub(),
         };
         element._handleSelection(selection);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 119,
           start_character: 10,
           end_line: 120,
@@ -394,43 +397,43 @@
         const startContent = stubContent(119, 'right');
         const endContent = stubContent(120, 'right');
         emulateSelection(startContent.firstChild, 10, endContent.firstChild, 2);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 119,
           start_character: 10,
           end_line: 120,
           end_character: 2,
         });
-        assert.equal(getActionSide(), 'right');
+        assert.equal(side, 'right');
       });
 
       test('collapsed', () => {
         const content = stubContent(138, 'left');
         emulateSelection(content.firstChild, 5, content.firstChild, 5);
         assert.isOk(window.getSelection().getRangeAt(0).startContainer);
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('starts inside hl', () => {
         const content = stubContent(140, 'left');
         const hl = content.querySelector('.foo');
         emulateSelection(hl.firstChild, 2, hl.nextSibling, 7);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 8,
           end_line: 140,
           end_character: 23,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('ends inside hl', () => {
         const content = stubContent(140, 'left');
         const hl = content.querySelector('.bar');
         emulateSelection(hl.previousSibling, 2, hl.firstChild, 3);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 18,
           end_line: 140,
@@ -442,14 +445,14 @@
         const content = stubContent(140, 'left');
         const hl = content.querySelectorAll('hl')[4];
         emulateSelection(content.firstChild, 2, hl.firstChild, 2);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 2,
           end_line: 140,
           end_character: 61,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('starts outside of diff', () => {
@@ -458,21 +461,21 @@
 
         emulateSelection(contentTd.previousElementSibling, 0,
             contentText.firstChild, 2);
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('ends outside of diff', () => {
         const content = stubContent(140, 'left');
         emulateSelection(content.nextElementSibling.firstChild, 2,
             content.firstChild, 2);
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('starts and ends on different sides', () => {
         const startContent = stubContent(140, 'left');
         const endContent = stubContent(130, 'right');
         emulateSelection(startContent.firstChild, 2, endContent.firstChild, 2);
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('starts in comment thread element', () => {
@@ -481,14 +484,14 @@
             '.comment-thread');
         const endContent = stubContent(141, 'left');
         emulateSelection(comment.firstChild, 2, endContent.firstChild, 4);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 83,
           end_line: 141,
           end_character: 4,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('ends in comment thread element', () => {
@@ -496,14 +499,14 @@
         const comment = content.parentElement.querySelector(
             '.comment-thread');
         emulateSelection(content.firstChild, 4, comment.firstChild, 1);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 4,
           end_line: 140,
           end_character: 83,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('starts in context element', () => {
@@ -512,7 +515,7 @@
         const content = stubContent(146, 'right');
         emulateSelection(contextControl, 0, content.firstChild, 7);
         // TODO (viktard): Select nearest line.
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('ends in context element', () => {
@@ -521,35 +524,35 @@
         const content = stubContent(141, 'left');
         emulateSelection(content.firstChild, 2, contextControl, 1);
         // TODO (viktard): Select nearest line.
-        assert.isFalse(element.isRangeSelected());
+        assert.isFalse(!!element.selectedRange);
       });
 
       test('selection containing context element', () => {
         const startContent = stubContent(130, 'right');
         const endContent = stubContent(146, 'right');
         emulateSelection(startContent.firstChild, 3, endContent.firstChild, 14);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 130,
           start_character: 3,
           end_line: 146,
           end_character: 14,
         });
-        assert.equal(getActionSide(), 'right');
+        assert.equal(side, 'right');
       });
 
       test('ends at a tab', () => {
         const content = stubContent(140, 'left');
         emulateSelection(
             content.firstChild, 1, content.querySelector('span'), 0);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 1,
           end_line: 140,
           end_character: 51,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('starts at a tab', () => {
@@ -557,14 +560,14 @@
         emulateSelection(
             content.querySelectorAll('hl')[3], 0,
             content.querySelectorAll('span')[1].nextSibling, 1);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 140,
           start_character: 51,
           end_line: 140,
           end_character: 71,
         });
-        assert.equal(getActionSide(), 'left');
+        assert.equal(side, 'left');
       });
 
       test('properly accounts for syntax highlighting', () => {
@@ -593,14 +596,14 @@
         const startContent = stubContent(119, 'right');
         const endContent = stubContent(120, 'right');
         emulateSelection(startContent.firstChild, 0, endContent.firstChild, 0);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 119,
           start_character: 0,
           end_line: 119,
           end_character: element._getLength(startContent),
         });
-        assert.equal(getActionSide(), 'right');
+        assert.equal(side, 'right');
       });
 
       test('_fixTripleClickSelection empty line', () => {
@@ -608,14 +611,14 @@
         const endContent = stubContent(165, 'left');
         emulateSelection(startContent.firstChild, 0,
             endContent.parentElement.previousElementSibling, 0);
-        assert.isTrue(element.isRangeSelected());
-        assert.deepEqual(getActionRange(), {
+        const {range, side} = element.selectedRange;
+        assert.deepEqual(range, {
           start_line: 146,
           start_character: 0,
           end_line: 146,
           end_character: 84,
         });
-        assert.equal(getActionSide(), 'right');
+        assert.equal(side, 'right');
       });
     });
   });
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.js b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.js
index 54398b8..f5dc438 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host.js
@@ -69,14 +69,22 @@
   };
 
   /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  /**
    * Wrapper around gr-diff.
    *
    * Webcomponent fetching diffs and related data from restAPI and passing them
    * to the presentational gr-diff for rendering.
    */
-  Polymer({
-    is: 'gr-diff-host',
-
+  class GrDiffHost extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff-host'; }
     /**
      * Fired when the user selects a line.
      * @event line-selected
@@ -94,188 +102,198 @@
      * @event diff-comments-modified
      */
 
-    properties: {
-      changeNum: String,
-      noAutoRender: {
-        type: Boolean,
-        value: false,
-      },
-      /** @type {?} */
-      patchRange: Object,
-      path: String,
-      prefs: {
-        type: Object,
-      },
-      projectName: String,
-      displayLine: {
-        type: Boolean,
-        value: false,
-      },
-      isImageDiff: {
-        type: Boolean,
-        computed: '_computeIsImageDiff(diff)',
-        notify: true,
-      },
-      commitRange: Object,
-      filesWeblinks: {
-        type: Object,
-        value() {
-          return {};
+    static get properties() {
+      return {
+        changeNum: String,
+        noAutoRender: {
+          type: Boolean,
+          value: false,
         },
-        notify: true,
-      },
-      hidden: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-      noRenderOnPrefsChange: {
-        type: Boolean,
-        value: false,
-      },
-      comments: {
-        type: Object,
-        observer: '_commentsChanged',
-      },
-      lineWrapping: {
-        type: Boolean,
-        value: false,
-      },
-      viewMode: {
-        type: String,
-        value: DiffViewMode.SIDE_BY_SIDE,
-      },
+        /** @type {?} */
+        patchRange: Object,
+        path: String,
+        prefs: {
+          type: Object,
+        },
+        projectName: String,
+        displayLine: {
+          type: Boolean,
+          value: false,
+        },
+        isImageDiff: {
+          type: Boolean,
+          computed: '_computeIsImageDiff(diff)',
+          notify: true,
+        },
+        commitRange: Object,
+        filesWeblinks: {
+          type: Object,
+          value() {
+            return {};
+          },
+          notify: true,
+        },
+        hidden: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+        noRenderOnPrefsChange: {
+          type: Boolean,
+          value: false,
+        },
+        comments: {
+          type: Object,
+          observer: '_commentsChanged',
+        },
+        lineWrapping: {
+          type: Boolean,
+          value: false,
+        },
+        viewMode: {
+          type: String,
+          value: DiffViewMode.SIDE_BY_SIDE,
+        },
 
-      /**
+        /**
        * Special line number which should not be collapsed into a shared region.
        * @type {{
        *  number: number,
        *  leftSide: {boolean}
        * }|null}
        */
-      lineOfInterest: Object,
+        lineOfInterest: Object,
 
-      /**
+        /**
        * If the diff fails to load, show the failure message in the diff rather
        * than bubbling the error up to the whole page. This is useful for when
        * loading inline diffs because one diff failing need not mark the whole
        * page with a failure.
        */
-      showLoadFailure: Boolean,
+        showLoadFailure: Boolean,
 
-      isBlameLoaded: {
-        type: Boolean,
-        notify: true,
-        computed: '_computeIsBlameLoaded(_blame)',
-      },
+        isBlameLoaded: {
+          type: Boolean,
+          notify: true,
+          computed: '_computeIsBlameLoaded(_blame)',
+        },
 
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
 
-      _loading: {
-        type: Boolean,
-        value: false,
-      },
+        _loading: {
+          type: Boolean,
+          value: false,
+        },
 
-      /** @type {?string} */
-      _errorMessage: {
-        type: String,
-        value: null,
-      },
+        /** @type {?string} */
+        _errorMessage: {
+          type: String,
+          value: null,
+        },
 
-      /** @type {?Object} */
-      _baseImage: Object,
-      /** @type {?Object} */
-      _revisionImage: Object,
-      /**
+        /** @type {?Object} */
+        _baseImage: Object,
+        /** @type {?Object} */
+        _revisionImage: Object,
+        /**
        * This is a DiffInfo object.
        */
-      diff: {
-        type: Object,
-        notify: true,
-      },
+        diff: {
+          type: Object,
+          notify: true,
+        },
 
-      /** @type {?Object} */
-      _blame: {
-        type: Object,
-        value: null,
-      },
+        /** @type {?Object} */
+        _blame: {
+          type: Object,
+          value: null,
+        },
 
-      /**
+        /**
        * @type {!Array<!Gerrit.CoverageRange>}
        */
-      _coverageRanges: {
-        type: Array,
-        value: () => [],
-      },
+        _coverageRanges: {
+          type: Array,
+          value: () => [],
+        },
 
-      _loadedWhitespaceLevel: String,
+        _loadedWhitespaceLevel: String,
 
-      _parentIndex: {
-        type: Number,
-        computed: '_computeParentIndex(patchRange.*)',
-      },
+        _parentIndex: {
+          type: Number,
+          computed: '_computeParentIndex(patchRange.*)',
+        },
 
-      _syntaxHighlightingEnabled: {
-        type: Boolean,
-        computed:
+        _syntaxHighlightingEnabled: {
+          type: Boolean,
+          computed:
           '_isSyntaxHighlightingEnabled(prefs.*, diff)',
-      },
+        },
 
-      _layers: {
-        type: Array,
-        value: [],
-      },
-    },
+        _layers: {
+          type: Array,
+          value: [],
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-    ],
-
-    listeners: {
-      // These are named inconsistently for a reason:
-      // The create-comment event is fired to indicate that we should
-      // create a comment.
-      // The comment-* events are just notifying that the comments did already
-      // change in some way, and that we should update any models we may want
-      // to keep in sync.
-      'create-comment': '_handleCreateComment',
-      'comment-discard': '_handleCommentDiscard',
-      'comment-update': '_handleCommentUpdate',
-      'comment-save': '_handleCommentSave',
-
-      'render-start': '_handleRenderStart',
-      'render-content': '_handleRenderContent',
-
-      'normalize-range': '_handleNormalizeRange',
-    },
-
-    observers: [
-      '_whitespaceChanged(prefs.ignore_whitespace, _loadedWhitespaceLevel,' +
+    static get observers() {
+      return [
+        '_whitespaceChanged(prefs.ignore_whitespace, _loadedWhitespaceLevel,' +
           ' noRenderOnPrefsChange)',
-      '_syntaxHighlightingChanged(noRenderOnPrefsChange, prefs.*)',
-    ],
+        '_syntaxHighlightingChanged(noRenderOnPrefsChange, prefs.*)',
+      ];
+    }
+
+    created() {
+      super.created();
+      this.addEventListener(
+          // These are named inconsistently for a reason:
+          // The create-comment event is fired to indicate that we should
+          // create a comment.
+          // The comment-* events are just notifying that the comments did already
+          // change in some way, and that we should update any models we may want
+          // to keep in sync.
+          'create-comment',
+          e => this._handleCreateComment(e));
+      this.addEventListener('comment-discard',
+          e => this._handleCommentDiscard(e));
+      this.addEventListener('comment-update',
+          e => this._handleCommentUpdate(e));
+      this.addEventListener('comment-save',
+          e => this._handleCommentSave(e));
+      this.addEventListener('render-start',
+          () => this._handleRenderStart());
+      this.addEventListener('render-content',
+          () => this._handleRenderContent());
+      this.addEventListener('normalize-range',
+          event => this._handleNormalizeRange(event));
+      this.addEventListener('diff-context-expanded',
+          event => this._handleDiffContextExpanded(event));
+    }
 
     ready() {
+      super.ready();
       if (this._canReload()) {
         this.reload();
       }
-    },
+    }
 
     attached() {
+      super.attached();
       this._getLoggedIn().then(loggedIn => {
         this._loggedIn = loggedIn;
       });
-    },
+    }
 
     /**
-     * @param {boolean=} haveParamsChanged ends reporting events that started
-     * on location change.
+     * @param {boolean=} shouldReportMetric indicate a new Diff Page. This is a
+     * signal to report metrics event that started on location change.
      * @return {!Promise}
      **/
-    reload(haveParamsChanged) {
+    reload(shouldReportMetric) {
       this._loading = true;
       this._errorMessage = null;
       const whitespaceLevel = this._getIgnoreWhitespace();
@@ -288,7 +306,7 @@
       }
       this._layers = layers;
 
-      if (haveParamsChanged) {
+      if (shouldReportMetric) {
         // We listen on render viewport only on DiffPage (on paramsChanged)
         this._listenToViewportRender();
       }
@@ -349,6 +367,11 @@
                   resolve();
                 }
                 this.removeEventListener('render', callback);
+                if (shouldReportMetric) {
+                  // We report diffViewContentDisplayed only on reload caused
+                  // by params changed - expected only on Diff Page.
+                  this.$.reporting.diffViewContentDisplayed();
+                }
               };
               this.addEventListener('render', callback);
               this.diff = diff;
@@ -358,7 +381,7 @@
             console.warn('Error encountered loading diff:', err);
           })
           .then(() => { this._loading = false; });
-    },
+    }
 
     _getFilesWeblinks(diff) {
       if (!this.commitRange) {
@@ -372,26 +395,30 @@
             this.projectName, this.commitRange.commit, this.path,
             {weblinks: diff && diff.meta_b && diff.meta_b.web_links}),
       };
-    },
+    }
 
     /** Cancel any remaining diff builder rendering work. */
     cancel() {
       this.$.diff.cancel();
-    },
+    }
 
     /** @return {!Array<!HTMLElement>} */
     getCursorStops() {
       return this.$.diff.getCursorStops();
-    },
+    }
 
     /** @return {boolean} */
     isRangeSelected() {
       return this.$.diff.isRangeSelected();
-    },
+    }
+
+    createRangeComment() {
+      return this.$.diff.createRangeComment();
+    }
 
     toggleLeftDiff() {
       this.$.diff.toggleLeftDiff();
-    },
+    }
 
     /**
      * Load and display blame information for the base of the diff.
@@ -408,12 +435,12 @@
 
             this._blame = blame;
           });
-    },
+    }
 
     /** Unload blame information for the diff. */
     clearBlame() {
       this._blame = null;
-    },
+    }
 
     /**
      * The thread elements in this diff, in no particular order.
@@ -422,31 +449,31 @@
     getThreadEls() {
       return Array.from(
           Polymer.dom(this.$.diff).querySelectorAll('.comment-thread'));
-    },
+    }
 
     /** @param {HTMLElement} el */
     addDraftAtLine(el) {
       this.$.diff.addDraftAtLine(el);
-    },
+    }
 
     clearDiffContent() {
       this.$.diff.clearDiffContent();
-    },
+    }
 
     expandAllContext() {
       this.$.diff.expandAllContext();
-    },
+    }
 
     /** @return {!Promise} */
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     /** @return {boolean}} */
     _canReload() {
       return !!this.changeNum && !!this.patchRange && !!this.path &&
           !this.noAutoRender;
-    },
+    }
 
     /** @return {!Promise<!Object>} */
     _getDiff() {
@@ -462,7 +489,7 @@
             reject)
             .then(resolve);
       });
-    },
+    }
 
     _handleGetDiffError(response) {
       // Loading the diff may respond with 409 if the file is too large. In this
@@ -482,7 +509,7 @@
       }
 
       this.fire('page-error', {response});
-    },
+    }
 
     /**
      * Report info about the diff response.
@@ -511,7 +538,7 @@
       // digits. Diffs with no delta are considered 0%.
       const totalDelta = rebaseDelta + nonRebaseDelta;
       const percentRebaseDelta = !totalDelta ? 0 :
-          Math.round(100 * rebaseDelta / totalDelta);
+        Math.round(100 * rebaseDelta / totalDelta);
 
       // Report the due_to_rebase percentage in the "diff" category when
       // applicable.
@@ -523,7 +550,7 @@
         this.$.reporting.reportInteraction(EVENT_NONZERO_REBASE,
             percentRebaseDelta);
       }
-    },
+    }
 
     /**
      * @param {Object} diff
@@ -540,7 +567,7 @@
         this._revisionImage = null;
         return Promise.resolve();
       }
-    },
+    }
 
     /**
      * @param {Object} diff
@@ -548,7 +575,7 @@
      */
     _computeIsImageDiff(diff) {
       return isImageDiff(diff);
-    },
+    }
 
     _commentsChanged(newComments) {
       const allComments = [];
@@ -569,7 +596,7 @@
         const threadEl = this._createThreadElement(thread);
         this._attachThreadElement(threadEl);
       }
-    },
+    }
 
     /**
      * @param {!Array<!Object>} comments
@@ -588,7 +615,7 @@
         // thread and append to it.
         if (comment.in_reply_to) {
           const thread = threads.find(thread =>
-              thread.comments.some(c => c.id === comment.in_reply_to));
+            thread.comments.some(c => c.id === comment.in_reply_to));
           if (thread) {
             thread.comments.push(comment);
             continue;
@@ -611,7 +638,7 @@
         threads.push(newThread);
       }
       return threads;
-    },
+    }
 
     /**
      * @param {Object} blame
@@ -619,7 +646,7 @@
      */
     _computeIsBlameLoaded(blame) {
       return !!blame;
-    },
+    }
 
     /**
      * @param {Object} diff
@@ -628,7 +655,7 @@
     _getImages(diff) {
       return this.$.restAPI.getImagesForDiff(this.changeNum, diff,
           this.patchRange);
-    },
+    }
 
     /** @param {CustomEvent} e */
     _handleCreateComment(e) {
@@ -638,7 +665,7 @@
       threadEl.addOrEditDraft(lineNum, range);
 
       this.$.reporting.recordDraftInteraction();
-    },
+    }
 
     /**
      * Gets or creates a comment thread at a given location.
@@ -665,18 +692,18 @@
         this._attachThreadElement(threadEl);
       }
       return threadEl;
-    },
+    }
 
     _attachThreadElement(threadEl) {
       Polymer.dom(this.$.diff).appendChild(threadEl);
-    },
+    }
 
     _clearThreads() {
       for (const threadEl of this.getThreadEls()) {
         const parent = Polymer.dom(threadEl).parentNode;
         Polymer.dom(parent).removeChild(threadEl);
       }
-    },
+    }
 
     _createThreadElement(thread) {
       const threadEl = document.createElement('gr-comment-thread');
@@ -707,7 +734,7 @@
       };
       threadEl.addEventListener('thread-discard', threadDiscardListener);
       return threadEl;
-    },
+    }
 
     /**
      * Gets a comment thread element at a given location.
@@ -729,14 +756,14 @@
       }
       function matchesRange(threadEl) {
         const threadRange = /** @type {!Gerrit.Range} */(
-            JSON.parse(threadEl.getAttribute('range')));
+          JSON.parse(threadEl.getAttribute('range')));
         return Gerrit.rangesEqual(threadRange, range);
       }
 
       const filteredThreadEls = this._filterThreadElsForLocation(
           this.getThreadEls(), line, commentSide).filter(matchesRange);
       return filteredThreadEls.length ? filteredThreadEls[0] : null;
-    },
+    }
 
     /**
      * @param {!Array<!HTMLElement>} threadEls
@@ -780,15 +807,15 @@
         matchers.push(matchesFileComment);
       }
       return threadEls.filter(threadEl =>
-          matchers.some(matcher => matcher(threadEl)));
-    },
+        matchers.some(matcher => matcher(threadEl)));
+    }
 
     _getIgnoreWhitespace() {
       if (!this.prefs || !this.prefs.ignore_whitespace) {
         return WHITESPACE_IGNORE_NONE;
       }
       return this.prefs.ignore_whitespace;
-    },
+    }
 
     _whitespaceChanged(
         preferredWhitespaceLevel, loadedWhitespaceLevel,
@@ -806,7 +833,7 @@
           !noRenderOnPrefsChange) {
         this.reload();
       }
-    },
+    }
 
     _syntaxHighlightingChanged(noRenderOnPrefsChange, prefsChangeRecord) {
       // Polymer 2: check for undefined
@@ -824,7 +851,7 @@
       if (!noRenderOnPrefsChange) {
         this.reload();
       }
-    },
+    }
 
     /**
      * @param {Object} patchRangeRecord
@@ -832,8 +859,8 @@
      */
     _computeParentIndex(patchRangeRecord) {
       return this.isMergeParent(patchRangeRecord.base.basePatchNum) ?
-          this.getParentIndex(patchRangeRecord.base.basePatchNum) : null;
-    },
+        this.getParentIndex(patchRangeRecord.base.basePatchNum) : null;
+    }
 
     _handleCommentSave(e) {
       const comment = e.detail.comment;
@@ -841,13 +868,13 @@
       const idx = this._findDraftIndex(comment, side);
       this.set(['comments', side, idx], comment);
       this._handleCommentSaveOrDiscard();
-    },
+    }
 
     _handleCommentDiscard(e) {
       const comment = e.detail.comment;
       this._removeComment(comment);
       this._handleCommentSaveOrDiscard();
-    },
+    }
 
     /**
      * Closure annotation for Polymer.prototype.push is off. Submitted PR:
@@ -868,17 +895,17 @@
       } else { // Create new draft.
         this.push(['comments', side], comment);
       }
-    },
+    }
 
     _handleCommentSaveOrDiscard() {
       this.dispatchEvent(new CustomEvent(
           'diff-comments-modified', {bubbles: true, composed: true}));
-    },
+    }
 
     _removeComment(comment) {
       const side = comment.__commentSide;
       this._removeCommentFromSide(comment, side);
-    },
+    }
 
     _removeCommentFromSide(comment, side) {
       let idx = this._findCommentIndex(comment, side);
@@ -888,7 +915,7 @@
       if (idx !== -1) {
         this.splice('comments.' + side, idx, 1);
       }
-    },
+    }
 
     /** @return {number} */
     _findCommentIndex(comment, side) {
@@ -896,7 +923,7 @@
         return -1;
       }
       return this.comments[side].findIndex(item => item.id === comment.id);
-    },
+    }
 
     /** @return {number} */
     _findDraftIndex(comment, side) {
@@ -905,7 +932,7 @@
       }
       return this.comments[side].findIndex(
           item => item.__draftID === comment.__draftID);
-    },
+    }
 
     _isSyntaxHighlightingEnabled(preferenceChangeRecord, diff) {
       if (!preferenceChangeRecord ||
@@ -916,7 +943,7 @@
       }
       return !this._anyLineTooLong(diff) &&
           this.$.diff.getDiffLength(diff) <= SYNTAX_MAX_DIFF_LENGTH;
-    },
+    }
 
     /**
      * @return {boolean} whether any of the lines in diff are longer
@@ -926,11 +953,11 @@
       if (!diff) return false;
       return diff.content.some(section => {
         const lines = section.ab ?
-              section.ab :
-              (section.a || []).concat(section.b || []);
+          section.ab :
+          (section.a || []).concat(section.b || []);
         return lines.some(line => line.length >= SYNTAX_MAX_LINE_LENGTH);
       });
-    },
+    }
 
     _listenToViewportRender() {
       const renderUpdateListener = start => {
@@ -941,22 +968,28 @@
       };
 
       this.$.syntaxLayer.addListener(renderUpdateListener);
-    },
+    }
 
     _handleRenderStart() {
       this.$.reporting.time(TimingLabel.TOTAL);
       this.$.reporting.time(TimingLabel.CONTENT);
-    },
+    }
 
     _handleRenderContent() {
       this.$.reporting.timeEnd(TimingLabel.CONTENT);
-      this.$.reporting.diffViewContentDisplayed();
-    },
+    }
 
     _handleNormalizeRange(event) {
       this.$.reporting.reportInteraction('normalize-range',
           `Modified invalid comment range on l. ${event.detail.lineNum}` +
           ` of the ${event.detail.side} side`);
-    },
-  });
+    }
+
+    _handleDiffContextExpanded(event) {
+      this.$.reporting.reportInteraction(
+          'diff-context-expanded', event.detail.numLines);
+    }
+  }
+
+  customElements.define(GrDiffHost.is, GrDiffHost);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
index 16b7728..ea94441 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-host/gr-diff-host_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -58,7 +58,6 @@
       sandbox.restore();
     });
 
-
     suite('plugin layers', () => {
       const pluginLayers = [{annotate: () => {}}, {annotate: () => {}}];
       setup(() => {
@@ -320,7 +319,7 @@
         element.patchRange = {};
         element.$.restAPI.getDiffPreferences().then(prefs => {
           element.prefs = prefs;
-          return element.reload();
+          return element.reload(true);
         });
         // Multiple cascading microtasks are scheduled.
         setTimeout(() => {
@@ -509,7 +508,7 @@
               'getB64FileContents',
               (changeId, patchNum, path, opt_parentIndex) => {
                 return Promise.resolve(opt_parentIndex === 1 ? mockFile1 :
-                    mockFile2);
+                  mockFile2);
               });
 
           element.patchRange = {basePatchNum: 'PARENT', patchNum: 1};
@@ -1261,7 +1260,6 @@
       assert.equal(threads[0].isOnParent, false);
       assert.equal(threads[0].patchNum, 2);
 
-
       // Try to fetch a thread with a different range.
       range = {
         start_line: 1,
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.js b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.js
index 88dd91a..8d8785a 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector.js
@@ -17,34 +17,38 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-diff-mode-selector',
+  class GrDiffModeSelector extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-diff-mode-selector'; }
 
-    properties: {
-      mode: {
-        type: String,
-        notify: true,
-      },
+    static get properties() {
+      return {
+        mode: {
+          type: String,
+          notify: true,
+        },
 
-      /**
+        /**
        * If set to true, the user's preference will be updated every time a
        * button is tapped. Don't set to true if there is no user.
        */
-      saveOnChange: {
-        type: Boolean,
-        value: false,
-      },
-
-      /** @type {?} */
-      _VIEW_MODES: {
-        type: Object,
-        readOnly: true,
-        value: {
-          SIDE_BY_SIDE: 'SIDE_BY_SIDE',
-          UNIFIED: 'UNIFIED_DIFF',
+        saveOnChange: {
+          type: Boolean,
+          value: false,
         },
-      },
-    },
+
+        /** @type {?} */
+        _VIEW_MODES: {
+          type: Object,
+          readOnly: true,
+          value: {
+            SIDE_BY_SIDE: 'SIDE_BY_SIDE',
+            UNIFIED: 'UNIFIED_DIFF',
+          },
+        },
+      };
+    }
 
     /**
      * Set the mode. If save on change is enabled also update the preference.
@@ -54,18 +58,20 @@
         this.$.restAPI.savePreferences({diff_view: newMode});
       }
       this.mode = newMode;
-    },
+    }
 
     _computeSelectedClass(diffViewMode, buttonViewMode) {
       return buttonViewMode === diffViewMode ? 'selected' : '';
-    },
+    }
 
     _handleSideBySideTap() {
       this.setMode(this._VIEW_MODES.SIDE_BY_SIDE);
-    },
+    }
 
     _handleUnifiedTap() {
       this.setMode(this._VIEW_MODES.UNIFIED);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffModeSelector.is, GrDiffModeSelector);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector_test.html b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector_test.html
index adeaa15..333a3d6 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-mode-selector/gr-diff-mode-selector_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-mode-selector</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.js b/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.js
index 6ecd4d6..2d79311 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-preferences-dialog/gr-diff-preferences-dialog.js
@@ -17,39 +17,44 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-diff-preferences-dialog',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrDiffPreferencesDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff-preferences-dialog'; }
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      diffPrefs: Object,
+        diffPrefs: Object,
 
-      _diffPrefsChanged: Boolean,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+        _diffPrefsChanged: Boolean,
+      };
+    }
 
     getFocusStops() {
       return {
         start: this.$.diffPreferences.$.contextSelect,
         end: this.$.saveButton,
       };
-    },
+    }
 
     resetFocus() {
       this.$.diffPreferences.$.contextSelect.focus();
-    },
+    }
 
     _computeHeaderClass(changed) {
       return changed ? 'edited' : '';
-    },
+    }
 
     _handleCancelDiff(e) {
       e.stopPropagation();
       this.$.diffPrefsOverlay.close();
-    },
+    }
 
     open() {
       this.$.diffPrefsOverlay.open().then(() => {
@@ -57,7 +62,7 @@
         this.$.diffPrefsOverlay.setFocusStops(focusStops);
         this.resetFocus();
       });
-    },
+    }
 
     _handleSaveDiffPreferences() {
       this.$.diffPreferences.save().then(() => {
@@ -65,6 +70,8 @@
 
         this.$.diffPrefsOverlay.close();
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffPreferencesDialog.is, GrDiffPreferencesDialog);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.js b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.js
index 4716544..817da45 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor.js
@@ -64,71 +64,77 @@
    *    that the part that is within the context or has comments is shown, while
    *    the rest is not.
    */
-  Polymer({
-    is: 'gr-diff-processor',
+  class GrDiffProcessor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-diff-processor'; }
 
-    properties: {
+    static get properties() {
+      return {
 
-      /**
+        /**
        * The amount of context around collapsed groups.
        */
-      context: Number,
+        context: Number,
 
-      /**
+        /**
        * The array of groups output by the processor.
        */
-      groups: {
-        type: Array,
-        notify: true,
-      },
+        groups: {
+          type: Array,
+          notify: true,
+        },
 
-      /**
+        /**
        * Locations that should not be collapsed, including the locations of
        * comments.
        */
-      keyLocations: {
-        type: Object,
-        value() { return {left: {}, right: {}}; },
-      },
+        keyLocations: {
+          type: Object,
+          value() { return {left: {}, right: {}}; },
+        },
 
-      /**
+        /**
        * The maximum number of lines to process synchronously.
        */
-      _asyncThreshold: {
-        type: Number,
-        value: 64,
-      },
+        _asyncThreshold: {
+          type: Number,
+          value: 64,
+        },
 
-      /** @type {?number} */
-      _nextStepHandle: Number,
-      /**
+        /** @type {?number} */
+        _nextStepHandle: Number,
+        /**
        * The promise last returned from `process()` while the asynchronous
        * processing is running - `null` otherwise. Provides a `cancel()`
        * method that rejects it with `{isCancelled: true}`.
        * @type {?Object}
        */
-      _processPromise: {
-        type: Object,
-        value: null,
-      },
-      _isScrolling: Boolean,
-    },
+        _processPromise: {
+          type: Object,
+          value: null,
+        },
+        _isScrolling: Boolean,
+      };
+    }
 
     attached() {
+      super.attached();
       this.listen(window, 'scroll', '_handleWindowScroll');
-    },
+    }
 
     detached() {
+      super.detached();
       this.cancel();
       this.unlisten(window, 'scroll', '_handleWindowScroll');
-    },
+    }
 
     _handleWindowScroll() {
       this._isScrolling = true;
       this.debounce('resetIsScrolling', () => {
         this._isScrolling = false;
       }, 50);
-    },
+    }
 
     /**
      * Asynchronously process the diff chunks into groups. As it processes, it
@@ -150,7 +156,6 @@
       // so finish processing.
       if (isBinary) { return Promise.resolve(); }
 
-
       this._processPromise = util.makeCancelable(
           new Promise(resolve => {
             const state = {
@@ -197,7 +202,7 @@
           }));
       return this._processPromise
           .finally(() => { this._processPromise = null; });
-    },
+    }
 
     /**
      * Cancel any jobs that are running.
@@ -210,7 +215,7 @@
       if (this._processPromise) {
         this._processPromise.cancel();
       }
-    },
+    }
 
     /**
      * Process the next uncollapsible chunk, or the next collapsible chunks.
@@ -237,15 +242,15 @@
 
       return this._processCollapsibleChunks(
           state, chunks, firstUncollapsibleChunkIndex);
-    },
+    }
 
     _linesLeft(chunk) {
       return chunk.ab || chunk.a || [];
-    },
+    }
 
     _linesRight(chunk) {
       return chunk.ab || chunk.b || [];
-    },
+    }
 
     _firstUncollapsibleChunkIndex(chunks, offset) {
       let chunkIndex = offset;
@@ -254,11 +259,11 @@
         chunkIndex++;
       }
       return chunkIndex;
-    },
+    }
 
     _isCollapsibleChunk(chunk) {
       return (chunk.ab || chunk.common) && !chunk.keyLocation;
-    },
+    }
 
     /**
      * Process a stretch of collapsible chunks.
@@ -290,7 +295,7 @@
       if (this.context !== WHOLE_FILE) {
         const hiddenStart = state.chunkIndex === 0 ? 0 : this.context;
         const hiddenEnd = lineCount - (
-            firstUncollapsibleChunkIndex === chunks.length ?
+          firstUncollapsibleChunkIndex === chunks.length ?
             0 : this.context);
         groups = GrDiffGroup.hideInContextControl(
             groups, hiddenStart, hiddenEnd);
@@ -304,7 +309,7 @@
         groups,
         newChunkIndex: firstUncollapsibleChunkIndex,
       };
-    },
+    }
 
     _commonChunkLength(chunk) {
       console.assert(chunk.ab || chunk.common);
@@ -312,7 +317,7 @@
           !chunk.a || (chunk.b && chunk.a.length === chunk.b.length),
           `common chunk needs same number of a and b lines: `, chunk);
       return this._linesLeft(chunk).length;
-    },
+    }
 
     /**
      * @param {!Array<!Object>} chunks
@@ -328,7 +333,7 @@
         offsetRight += chunkLength;
         return group;
       });
-    },
+    }
 
     /**
      * @param {!Object} chunk
@@ -344,7 +349,7 @@
       group.dueToRebase = chunk.due_to_rebase;
       group.ignoredWhitespaceOnly = chunk.common;
       return group;
-    },
+    }
 
     _linesFromChunk(chunk, offsetLeft, offsetRight) {
       if (chunk.ab) {
@@ -367,7 +372,7 @@
             chunk[DiffHighlights.ADDED]));
       }
       return lines;
-    },
+    }
 
     /**
      * @param {string} lineType (GrDiffLine.Type)
@@ -381,7 +386,7 @@
         this._convertIntralineInfos(rows, opt_intralineInfos) : undefined;
       return rows.map((row, i) => this._lineFromRow(
           lineType, offset, offset, row, i, grDiffHighlights));
-    },
+    }
 
     /**
      * @param {string} type (GrDiffLine.Type)
@@ -404,15 +409,14 @@
         line.hasIntralineInfo = false;
       }
       return line;
-    },
+    }
 
     _makeFileComments() {
       const line = new GrDiffLine(GrDiffLine.Type.BOTH);
       line.beforeNumber = GrDiffLine.FILE;
       line.afterNumber = GrDiffLine.FILE;
       return new GrDiffGroup(GrDiffGroup.Type.BOTH, [line]);
-    },
-
+    }
 
     /**
      * Split chunks into smaller chunks of the same kind.
@@ -454,7 +458,7 @@
         }
       }
       return newChunks;
-    },
+    }
 
     /**
      * In order to show key locations, such as comments, out of the bounds of
@@ -483,7 +487,7 @@
 
         if (chunk.common && chunk.a.length != chunk.b.length) {
           throw new Error(
-            'DiffContent with common=true must always have equal length');
+              'DiffContent with common=true must always have equal length');
         }
         const numLines = this._commonChunkLength(chunk);
         const chunkEnds = this._findChunkEndsAtKeyLocations(
@@ -494,7 +498,7 @@
         if (chunk.ab) {
           result.push(...this._splitAtChunkEnds(chunk.ab, chunkEnds)
               .map(({lines, keyLocation}) =>
-                  Object.assign({}, chunk, {ab: lines, keyLocation})));
+                Object.assign({}, chunk, {ab: lines, keyLocation})));
         } else if (chunk.common) {
           const aChunks = this._splitAtChunkEnds(chunk.a, chunkEnds);
           const bChunks = this._splitAtChunkEnds(chunk.b, chunkEnds);
@@ -505,7 +509,7 @@
       }
 
       return result;
-    },
+    }
 
     /**
      * @return {!Array<{offset: number, keyLocation: boolean}>} Offsets of the
@@ -536,7 +540,7 @@
       }
 
       return result;
-    },
+    }
 
     _splitAtChunkEnds(lines, chunkEnds) {
       const result = [];
@@ -547,7 +551,7 @@
         lastChunkEndOffset = offset;
       }
       return result;
-    },
+    }
 
     /**
      * Converts `IntralineInfo`s return by the API to `GrLineHighlights` used
@@ -597,7 +601,7 @@
         normalized.push(lineHighlight);
       }
       return normalized;
-    },
+    }
 
     /**
      * If a group is an addition or a removal, break it down into smaller groups
@@ -627,7 +631,7 @@
             }
             return subChunk;
           });
-    },
+    }
 
     /**
      * Given an array and a size, return an array of arrays where no inner array
@@ -645,6 +649,8 @@
       const tail = array.slice(array.length - size);
 
       return this._breakdown(head, size).concat([tail]);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffProcessor.is, GrDiffProcessor);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.html b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.html
index c04b066..308428f 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-processor/gr-diff-processor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-processor test</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.js b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.js
index 055b200..0dc0fba 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection.js
@@ -30,35 +30,46 @@
 
   const getNewCache = () => { return {left: null, right: null}; };
 
-  Polymer({
-    is: 'gr-diff-selection',
+  /**
+    * @appliesMixin Gerrit.DomUtilMixin
+    */
+  class GrDiffSelection extends Polymer.mixinBehaviors( [
+    Gerrit.DomUtilBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff-selection'; }
 
-    properties: {
-      diff: Object,
-      /** @type {?Object} */
-      _cachedDiffBuilder: Object,
-      _linesCache: {
-        type: Object,
-        value: getNewCache(),
-      },
-    },
+    static get properties() {
+      return {
+        diff: Object,
+        /** @type {?Object} */
+        _cachedDiffBuilder: Object,
+        _linesCache: {
+          type: Object,
+          value: getNewCache(),
+        },
+      };
+    }
 
-    observers: [
-      '_diffChanged(diff)',
-    ],
+    static get observers() {
+      return [
+        '_diffChanged(diff)',
+      ];
+    }
 
-    listeners: {
-      copy: '_handleCopy',
-      down: '_handleDown',
-    },
-
-    behaviors: [
-      Gerrit.DomUtilBehavior,
-    ],
+    created() {
+      super.created();
+      this.addEventListener('copy',
+          e => this._handleCopy(e));
+      Polymer.Gestures.addListener(this, 'down',
+          e => this._handleDown(e));
+    }
 
     attached() {
+      super.attached();
       this.classList.add(SelectionClass.RIGHT);
-    },
+    }
 
     get diffBuilder() {
       if (!this._cachedDiffBuilder) {
@@ -66,11 +77,11 @@
             Polymer.dom(this).querySelector('gr-diff-builder');
       }
       return this._cachedDiffBuilder;
-    },
+    }
 
     _diffChanged() {
       this._linesCache = getNewCache();
-    },
+    }
 
     _handleDownOnRangeComment(node) {
       if (node &&
@@ -79,13 +90,13 @@
         this._setClasses([
           SelectionClass.COMMENT,
           node.commentSide === 'left' ?
-          SelectionClass.LEFT :
-          SelectionClass.RIGHT,
+            SelectionClass.LEFT :
+            SelectionClass.RIGHT,
         ]);
         return true;
       }
       return false;
-    },
+    }
 
     _handleDown(e) {
       // Handle the down event on comment thread in Polymer 2
@@ -106,8 +117,8 @@
         const side = this.diffBuilder.getSideByLineEl(lineEl);
 
         targetClasses.push(side === 'left' ?
-            SelectionClass.LEFT :
-            SelectionClass.RIGHT);
+          SelectionClass.LEFT :
+          SelectionClass.RIGHT);
 
         if (commentSelected) {
           targetClasses.push(SelectionClass.COMMENT);
@@ -115,7 +126,7 @@
       }
 
       this._setClasses(targetClasses);
-    },
+    }
 
     /**
      * Set the provided list of classes on the element, to the exclusion of all
@@ -138,11 +149,11 @@
           this.classList.add(_class);
         }
       }
-    },
+    }
 
     _getCopyEventTarget(e) {
       return Polymer.dom(e).rootTarget;
-    },
+    }
 
     /**
      * Utility function to determine whether an element is a descendant of
@@ -155,7 +166,7 @@
     _elementDescendedFromClass(element, className) {
       return this.descendedFromClass(element, className,
           this.diffBuilder.diffElement);
-    },
+    }
 
     _handleCopy(e) {
       let commentSelected = false;
@@ -175,7 +186,7 @@
         e.clipboardData.setData('Text', text);
         e.preventDefault();
       }
-    },
+    }
 
     /**
      * For Polymer 2, use shadowRoot.getSelection instead.
@@ -186,7 +197,7 @@
         diffHost.shadowRoot &&
         diffHost.shadowRoot.getSelection();
       return selection ? selection: window.getSelection();
-    },
+    }
 
     /**
      * Get the text of the current selection. If commentSelected is
@@ -225,7 +236,7 @@
 
       return this._getRangeFromDiff(startLineNum, range.startOffset, endLineNum,
           range.endOffset, side);
-    },
+    }
 
     /**
      * Query the diff object for the selected lines.
@@ -247,7 +258,7 @@
         lines[0] = lines[0].substring(startOffset);
       }
       return lines.join('\n');
-    },
+    }
 
     /**
      * Query the diff object for the lines from a particular side.
@@ -270,7 +281,7 @@
       }
       this._linesCache[side] = lines;
       return lines;
-    },
+    }
 
     /**
      * Query the diffElement for comments and check whether they lie inside the
@@ -308,7 +319,7 @@
       }
 
       return content.join('\n');
-    },
+    }
 
     /**
      * Given a DOM node, a selection, and a selection range, recursively get all
@@ -338,6 +349,8 @@
         }
       }
       return text;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffSelection.is, GrDiffSelection);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection_test.html b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection_test.html
index 0f5c6dd..6fe319d 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-selection/gr-diff-selection_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-selection</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -375,7 +375,6 @@
             'his is a differ');
       });
 
-
       test('multi level element as startContainer of range', () => {
         range.setStart(nodes[2].childNodes[1], 0);
         range.setEnd(nodes[2].childNodes[2], 7);
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
index 8158c96..4c401cf 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view.js
@@ -33,9 +33,23 @@
     UNIFIED: 'UNIFIED_DIFF',
   };
 
-  Polymer({
-    is: 'gr-diff-view',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.PathListMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrDiffView extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.PathListBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff-view'; }
     /**
      * Fired when the title of the page should change.
      *
@@ -48,154 +62,152 @@
      * @event show-alert
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      /**
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
+        /**
        * @type {{ diffMode: (string|undefined) }}
        */
-      changeViewState: {
-        type: Object,
-        notify: true,
-        value() { return {}; },
-        observer: '_changeViewStateChanged',
-      },
-      disableDiffPrefs: {
-        type: Boolean,
-        value: false,
-      },
-      _diffPrefsDisabled: {
-        type: Boolean,
-        computed: '_computeDiffPrefsDisabled(disableDiffPrefs, _loggedIn)',
-      },
-      /** @type {?} */
-      _patchRange: Object,
-      /** @type {?} */
-      _commitRange: Object,
-      /**
+        changeViewState: {
+          type: Object,
+          notify: true,
+          value() { return {}; },
+          observer: '_changeViewStateChanged',
+        },
+        disableDiffPrefs: {
+          type: Boolean,
+          value: false,
+        },
+        _diffPrefsDisabled: {
+          type: Boolean,
+          computed: '_computeDiffPrefsDisabled(disableDiffPrefs, _loggedIn)',
+        },
+        /** @type {?} */
+        _patchRange: Object,
+        /** @type {?} */
+        _commitRange: Object,
+        /**
        * @type {{
        *  subject: string,
        *  project: string,
        *  revisions: string,
        * }}
        */
-      _change: Object,
-      /** @type {?} */
-      _changeComments: Object,
-      _changeNum: String,
-      /**
+        _change: Object,
+        /** @type {?} */
+        _changeComments: Object,
+        _changeNum: String,
+        /**
        * This is a DiffInfo object.
        * This is retrieved and owned by a child component.
        */
-      _diff: Object,
-      // An array specifically formatted to be used in a gr-dropdown-list
-      // element for selected a file to view.
-      _formattedFiles: {
-        type: Array,
-        computed: '_formatFilesForDropdown(_fileList, _patchRange.patchNum, ' +
-            '_changeComments)',
-      },
-      // An sorted array of files, as returned by the rest API.
-      _fileList: {
-        type: Array,
-        value() { return []; },
-      },
-      _path: {
-        type: String,
-        observer: '_pathChanged',
-      },
-      _fileNum: {
-        type: Number,
-        computed: '_computeFileNum(_path, _formattedFiles)',
-      },
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _prefs: Object,
-      _localPrefs: Object,
-      _projectConfig: Object,
-      _userPrefs: Object,
-      _diffMode: {
-        type: String,
-        computed: '_getDiffViewMode(changeViewState.diffMode, _userPrefs)',
-      },
-      _isImageDiff: Boolean,
-      _filesWeblinks: Object,
+        _diff: Object,
+        // An array specifically formatted to be used in a gr-dropdown-list
+        // element for selected a file to view.
+        _formattedFiles: {
+          type: Array,
+          computed: '_formatFilesForDropdown(_fileList, ' +
+            '_patchRange.patchNum, _changeComments)',
+        },
+        // An sorted array of files, as returned by the rest API.
+        _fileList: {
+          type: Array,
+          value() { return []; },
+        },
+        _path: {
+          type: String,
+          observer: '_pathChanged',
+        },
+        _fileNum: {
+          type: Number,
+          computed: '_computeFileNum(_path, _formattedFiles)',
+        },
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _prefs: Object,
+        _localPrefs: Object,
+        _projectConfig: Object,
+        _userPrefs: Object,
+        _diffMode: {
+          type: String,
+          computed: '_getDiffViewMode(changeViewState.diffMode, _userPrefs)',
+        },
+        _isImageDiff: Boolean,
+        _filesWeblinks: Object,
 
-      /**
+        /**
        * Map of paths in the current change and patch range that have comments
        * or drafts or robot comments.
        */
-      _commentMap: Object,
+        _commentMap: Object,
 
-      _commentsForDiff: Object,
+        _commentsForDiff: Object,
 
-      /**
+        /**
        * Object to contain the path of the next and previous file in the current
        * change and patch range that has comments.
        */
-      _commentSkips: {
-        type: Object,
-        computed: '_computeCommentSkips(_commentMap, _fileList, _path)',
-      },
-      _panelFloatingDisabled: {
-        type: Boolean,
-        value: () => { return window.PANEL_FLOATING_DISABLED; },
-      },
-      _editMode: {
-        type: Boolean,
-        computed: '_computeEditMode(_patchRange.*)',
-      },
-      _isBlameLoaded: Boolean,
-      _isBlameLoading: {
-        type: Boolean,
-        value: false,
-      },
-      _allPatchSets: {
-        type: Array,
-        computed: 'computeAllPatchSets(_change, _change.revisions.*)',
-      },
-      _revisionInfo: {
-        type: Object,
-        computed: '_getRevisionInfo(_change)',
-      },
-      _reviewedFiles: {
-        type: Object,
-        value: () => new Set(),
-      },
-    },
+        _commentSkips: {
+          type: Object,
+          computed: '_computeCommentSkips(_commentMap, _fileList, _path)',
+        },
+        _panelFloatingDisabled: {
+          type: Boolean,
+          value: () => { return window.PANEL_FLOATING_DISABLED; },
+        },
+        _editMode: {
+          type: Boolean,
+          computed: '_computeEditMode(_patchRange.*)',
+        },
+        _isBlameLoaded: Boolean,
+        _isBlameLoading: {
+          type: Boolean,
+          value: false,
+        },
+        _allPatchSets: {
+          type: Array,
+          computed: 'computeAllPatchSets(_change, _change.revisions.*)',
+        },
+        _revisionInfo: {
+          type: Object,
+          computed: '_getRevisionInfo(_change)',
+        },
+        _reviewedFiles: {
+          type: Object,
+          value: () => new Set(),
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.PathListBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
+    static get observers() {
+      return [
+        '_getProjectConfig(_change.project)',
+        '_getFiles(_changeNum, _patchRange.*)',
+        '_setReviewedObserver(_loggedIn, params.*, _prefs)',
+      ];
+    }
 
-    observers: [
-      '_getProjectConfig(_change.project)',
-      '_getFiles(_changeNum, _patchRange.*)',
-      '_setReviewedObserver(_loggedIn, params.*, _prefs)',
-    ],
-
-    keyBindings: {
-      esc: '_handleEscKey',
-    },
+    get keyBindings() {
+      return {
+        esc: '_handleEscKey',
+      };
+    }
 
     keyboardShortcuts() {
       return {
@@ -230,37 +242,38 @@
         [this.Shortcut.EXPAND_ALL_COMMENT_THREADS]: null,
         [this.Shortcut.COLLAPSE_ALL_COMMENT_THREADS]: null,
       };
-    },
+    }
 
     attached() {
+      super.attached();
       this._getLoggedIn().then(loggedIn => {
         this._loggedIn = loggedIn;
       });
 
       this.$.cursor.push('diffs', this.$.diffHost);
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _getProjectConfig(project) {
       return this.$.restAPI.getProjectConfig(project).then(
           config => {
             this._projectConfig = config;
           });
-    },
+    }
 
     _getChangeDetail(changeNum) {
       return this.$.restAPI.getDiffChangeDetail(changeNum).then(change => {
         this._change = change;
         return change;
       });
-    },
+    }
 
     _getChangeEdit(changeNum) {
       return this.$.restAPI.getChangeEdit(this._changeNum);
-    },
+    }
 
     _getFiles(changeNum, patchRangeRecord) {
       // Polymer 2: check for undefined
@@ -272,27 +285,27 @@
       const patchRange = patchRangeRecord.base;
       return this.$.restAPI.getChangeFilePathsAsSpeciallySortedArray(
           changeNum, patchRange).then(files => {
-            this._fileList = files;
-          });
-    },
+        this._fileList = files;
+      });
+    }
 
     _getDiffPreferences() {
       return this.$.restAPI.getDiffPreferences().then(prefs => {
         this._prefs = prefs;
       });
-    },
+    }
 
     _getPreferences() {
       return this.$.restAPI.getPreferences();
-    },
+    }
 
     _getWindowWidth() {
       return window.innerWidth;
-    },
+    }
 
     _handleReviewedChange(e) {
       this._setReviewed(Polymer.dom(e).rootTarget.checked);
-    },
+    }
 
     _setReviewed(reviewed) {
       if (this._editMode) { return; }
@@ -301,12 +314,12 @@
         this.fire('show-alert', {message: ERR_REVIEW_STATUS});
         throw err;
       });
-    },
+    }
 
     _saveReviewedState(reviewed) {
       return this.$.restAPI.saveFileReviewed(this._changeNum,
           this._patchRange.patchNum, this._path, reviewed);
-    },
+    }
 
     _handleToggleFileReviewed(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -314,7 +327,7 @@
 
       e.preventDefault();
       this._setReviewed(!this.$.reviewed.checked);
-    },
+    }
 
     _handleEscKey(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -322,21 +335,21 @@
 
       e.preventDefault();
       this.$.diffHost.displayLine = false;
-    },
+    }
 
     _handleLeftPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
 
       e.preventDefault();
       this.$.cursor.moveLeft();
-    },
+    }
 
     _handleRightPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
 
       e.preventDefault();
       this.$.cursor.moveRight();
-    },
+    }
 
     _handlePrevLineOrFileWithComments(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -350,7 +363,7 @@
       e.preventDefault();
       this.$.diffHost.displayLine = true;
       this.$.cursor.moveUp();
-    },
+    }
 
     _handleNextLineOrFileWithComments(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -364,7 +377,7 @@
       e.preventDefault();
       this.$.diffHost.displayLine = true;
       this.$.cursor.moveDown();
-    },
+    }
 
     _moveToPreviousFileWithComment() {
       if (!this._commentSkips) { return; }
@@ -378,7 +391,7 @@
 
       Gerrit.Nav.navigateToDiff(this._change, this._commentSkips.previous,
           this._patchRange.patchNum, this._patchRange.basePatchNum);
-    },
+    }
 
     _moveToNextFileWithComment() {
       if (!this._commentSkips) { return; }
@@ -391,19 +404,14 @@
 
       Gerrit.Nav.navigateToDiff(this._change, this._commentSkips.next,
           this._patchRange.patchNum, this._patchRange.basePatchNum);
-    },
+    }
 
     _handleNewComment(e) {
-      if (this.shouldSuppressKeyboardShortcut(e)) { return; }
-      if (this.$.diffHost.isRangeSelected()) { return; }
-      if (this.modifierPressed(e)) { return; }
-
+      if (this.shouldSuppressKeyboardShortcut(e) ||
+          this.modifierPressed(e)) { return; }
       e.preventDefault();
-      const line = this.$.cursor.getTargetLineElement();
-      if (line) {
-        this.$.diffHost.addDraftAtLine(line);
-      }
-    },
+      this.$.cursor.createCommentInPlace();
+    }
 
     _handlePrevFile(e) {
       // Check for meta key to avoid overriding native chrome shortcut.
@@ -412,7 +420,7 @@
 
       e.preventDefault();
       this._navToFile(this._path, this._fileList, -1);
-    },
+    }
 
     _handleNextFile(e) {
       // Check for meta key to avoid overriding native chrome shortcut.
@@ -421,7 +429,7 @@
 
       e.preventDefault();
       this._navToFile(this._path, this._fileList, 1);
-    },
+    }
 
     _handleNextChunkOrCommentThread(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -433,7 +441,7 @@
         if (this.modifierPressed(e)) { return; }
         this.$.cursor.moveToNextChunk();
       }
-    },
+    }
 
     _handlePrevChunkOrCommentThread(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -445,7 +453,7 @@
         if (this.modifierPressed(e)) { return; }
         this.$.cursor.moveToPreviousChunk();
       }
-    },
+    }
 
     _handleOpenReplyDialogOrToggleLeftPane(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -463,7 +471,7 @@
       this.set('changeViewState.showReplyDialog', true);
       e.preventDefault();
       this._navToChangeView();
-    },
+    }
 
     _handleUpToChange(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -471,7 +479,7 @@
 
       e.preventDefault();
       this._navToChangeView();
-    },
+    }
 
     _handleCommaKey(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -480,7 +488,7 @@
 
       e.preventDefault();
       this.$.diffPreferencesDialog.open();
-    },
+    }
 
     _handleToggleDiffMode(e) {
       if (this.shouldSuppressKeyboardShortcut(e) ||
@@ -492,7 +500,7 @@
       } else {
         this.$.modeSelect.setMode(DiffViewMode.SIDE_BY_SIDE);
       }
-    },
+    }
 
     _navToChangeView() {
       if (!this._changeNum || !this._patchRange.patchNum) { return; }
@@ -500,7 +508,7 @@
           this._change,
           this._patchRange,
           this._change && this._change.revisions);
-    },
+    }
 
     _navToFile(path, fileList, direction) {
       const newPath = this._getNavLinkPath(path, fileList, direction);
@@ -516,7 +524,7 @@
 
       Gerrit.Nav.navigateToDiff(this._change, newPath.path,
           this._patchRange.patchNum, this._patchRange.basePatchNum);
-    },
+    }
 
     /**
      * @param {?string} path The path of the current file being shown.
@@ -540,7 +548,7 @@
             this._change && this._change.revisions);
       }
       return this._getDiffUrl(this._change, this._patchRange, newPath.path);
-    },
+    }
 
     /**
      * Gives an object representing the target of navigating either left or
@@ -566,8 +574,8 @@
       let idx = fileList.indexOf(path);
       if (idx === -1) {
         const file = direction > 0 ?
-            fileList[0] :
-            fileList[fileList.length - 1];
+          fileList[0] :
+          fileList[fileList.length - 1];
         return {path: file};
       }
 
@@ -580,7 +588,7 @@
       }
 
       return {path: fileList[idx]};
-    },
+    }
 
     _getReviewedFiles(changeNum, patchNum) {
       return this.$.restAPI.getReviewedFiles(changeNum, patchNum)
@@ -588,13 +596,13 @@
             this._reviewedFiles = new Set(files);
             return this._reviewedFiles;
           });
-    },
+    }
 
     _getReviewedStatus(editMode, changeNum, patchNum, path) {
       if (editMode) { return Promise.resolve(false); }
       return this._getReviewedFiles(changeNum, patchNum)
           .then(files => files.has(path));
-    },
+    }
 
     _paramsChanged(value) {
       if (value.view !== Gerrit.Nav.View.DIFF) { return; }
@@ -681,7 +689,7 @@
         // If diff view displayed has not ended yet, it ends here.
         this.$.reporting.diffViewDisplayed();
       });
-    },
+    }
 
     _changeViewStateChanged(changeViewState) {
       if (changeViewState.diffMode === null) {
@@ -690,7 +698,7 @@
           this.set('changeViewState.diffMode', prefs.default_diff_view);
         });
       }
-    },
+    }
 
     _setReviewedObserver(_loggedIn, paramsRecord, _prefs) {
       // Polymer 2: check for undefined
@@ -706,15 +714,15 @@
         // is specified.
         this._getReviewedStatus(this.editMode, this._changeNum,
             this._patchRange.patchNum, this._path).then(status => {
-              this.$.reviewed.checked = status;
-            });
+          this.$.reviewed.checked = status;
+        });
         return;
       }
 
       if (params.view === Gerrit.Nav.View.DIFF) {
         this._setReviewed(true);
       }
-    },
+    }
 
     /**
      * If the params specify a diff address then configure the diff cursor.
@@ -727,14 +735,14 @@
         this.$.cursor.side = DiffSides.RIGHT;
       }
       this.$.cursor.initialLineNumber = params.lineNum;
-    },
+    }
 
     _getLineOfInterest(params) {
       // If there is a line number specified, pass it along to the diff so that
       // it will not get collapsed.
       if (!params.lineNum) { return null; }
       return {number: params.lineNum, leftSide: params.leftSide};
-    },
+    }
 
     _pathChanged(path) {
       if (path) {
@@ -746,7 +754,7 @@
 
       this.set('changeViewState.selectedFileIndex',
           this._fileList.indexOf(path));
-    },
+    }
 
     _getDiffUrl(change, patchRange, path) {
       if ([change, patchRange, path].some(arg => arg === undefined)) {
@@ -754,7 +762,7 @@
       }
       return Gerrit.Nav.getUrlForDiff(change, path, patchRange.patchNum,
           patchRange.basePatchNum);
-    },
+    }
 
     _patchRangeStr(patchRange) {
       let patchStr = patchRange.patchNum;
@@ -763,7 +771,7 @@
         patchStr = patchRange.basePatchNum + '..' + patchRange.patchNum;
       }
       return patchStr;
-    },
+    }
 
     /**
      * When the latest patch of the change is selected (and there is no base
@@ -787,7 +795,7 @@
         basePatchNum = patchRange.basePatchNum;
       }
       return {patchNum, basePatchNum};
-    },
+    }
 
     _getChangePath(change, patchRange, revisions) {
       if ([change, patchRange].some(arg => arg === undefined)) {
@@ -796,16 +804,16 @@
       const range = this._getChangeUrlRange(patchRange, revisions);
       return Gerrit.Nav.getUrlForChange(change, range.patchNum,
           range.basePatchNum);
-    },
+    }
 
     _navigateToChange(change, patchRange, revisions) {
       const range = this._getChangeUrlRange(patchRange, revisions);
       Gerrit.Nav.navigateToChange(change, range.patchNum, range.basePatchNum);
-    },
+    }
 
     _computeChangePath(change, patchRangeRecord, revisions) {
       return this._getChangePath(change, patchRangeRecord.base, revisions);
-    },
+    }
 
     _formatFilesForDropdown(fileList, patchNum, changeComments) {
       // Polymer 2: check for undefined
@@ -829,7 +837,7 @@
         });
       }
       return dropdownContent;
-    },
+    }
 
     _computeCommentString(changeComments, patchNum, path) {
       const unresolvedCount = changeComments.computeUnresolvedNum(patchNum,
@@ -845,11 +853,11 @@
           (commentString && unresolvedString ? ', ' : '') +
           // Add parentheses around unresolved if it exists.
           (unresolvedString ? `${unresolvedString}` : '');
-    },
+    }
 
     _computePrefsButtonHidden(prefs, prefsDisabled) {
       return prefsDisabled || !prefs;
-    },
+    }
 
     _handleFileChange(e) {
       // This is when it gets set initially.
@@ -860,7 +868,7 @@
 
       Gerrit.Nav.navigateToDiff(this._change, path, this._patchRange.patchNum,
           this._patchRange.basePatchNum);
-    },
+    }
 
     _handleFileTap(e) {
       // async is needed so that that the click event is fired before the
@@ -868,7 +876,7 @@
       this.async(() => {
         this.$.dropdown.close();
       }, 1);
-    },
+    }
 
     _handlePatchChange(e) {
       const {basePatchNum, patchNum} = e.detail;
@@ -876,12 +884,12 @@
           this.patchNumEquals(patchNum, this._patchRange.patchNum)) { return; }
       Gerrit.Nav.navigateToDiff(
           this._change, this._path, patchNum, basePatchNum);
-    },
+    }
 
     _handlePrefsTap(e) {
       e.preventDefault();
       this.$.diffPreferencesDialog.open();
-    },
+    }
 
     /**
      * _getDiffViewMode: Get the diff view (side-by-side or unified) based on
@@ -906,11 +914,11 @@
       } else {
         return 'SIDE_BY_SIDE';
       }
-    },
+    }
 
     _computeModeSelectHideClass(isImageDiff) {
       return isImageDiff ? 'hide' : '';
-    },
+    }
 
     _onLineSelected(e, detail) {
       this.$.cursor.moveToLineNumber(detail.number, detail.side);
@@ -922,7 +930,7 @@
           this._change.project, this._path, this._patchRange.patchNum,
           this._patchRange.basePatchNum, number, leftSide);
       history.replaceState(null, '', url);
-    },
+    }
 
     _computeDownloadDropdownLinks(
         project, changeNum, patchRange, path, diff) {
@@ -961,7 +969,7 @@
       }
 
       return links;
-    },
+    }
 
     _computeDownloadFileLink(
         project, changeNum, patchRange, path, isBase) {
@@ -981,13 +989,13 @@
       }
 
       return url;
-    },
+    }
 
     _computeDownloadPatchLink(project, changeNum, patchRange, path) {
       let url = this.changeBaseURL(project, changeNum, patchRange.patchNum);
       url += '/patch?zip&path=' + encodeURIComponent(path);
       return url;
-    },
+    }
 
     _loadComments() {
       return this.$.commentAPI.loadAll(this._changeNum).then(comments => {
@@ -997,20 +1005,20 @@
         this._commentsForDiff = this._getCommentsForPath(this._path,
             this._patchRange, this._projectConfig);
       });
-    },
+    }
 
     _getPaths(patchRange) {
       return this._changeComments.getPaths(patchRange);
-    },
+    }
 
     _getCommentsForPath(path, patchRange, projectConfig) {
       return this._changeComments.getCommentsBySideForPath(path, patchRange,
           projectConfig);
-    },
+    }
 
     _getDiffDrafts() {
       return this.$.restAPI.getDiffDrafts(this._changeNum);
-    },
+    }
 
     _computeCommentSkips(commentMap, fileList, path) {
       // Polymer 2: check for undefined
@@ -1043,13 +1051,13 @@
       }
 
       return skips;
-    },
+    }
 
     _computeDiffClass(panelFloatingDisabled) {
       if (panelFloatingDisabled) {
         return 'noOverflow';
       }
-    },
+    }
 
     /**
      * @param {!Object} patchRangeRecord
@@ -1057,19 +1065,19 @@
     _computeEditMode(patchRangeRecord) {
       const patchRange = patchRangeRecord.base || {};
       return this.patchNumEquals(patchRange.patchNum, this.EDIT_NAME);
-    },
+    }
 
     /**
      * @param {boolean} editMode
      */
     _computeContainerClass(editMode) {
       return editMode ? 'editMode' : '';
-    },
+    }
 
     _computeBlameToggleLabel(loaded, loading) {
       if (loaded) { return 'Hide blame'; }
       return 'Show blame';
-    },
+    }
 
     /**
      * Load and display blame information if it has not already been loaded.
@@ -1091,15 +1099,15 @@
           .catch(() => {
             this._isBlameLoading = false;
           });
-    },
+    }
 
     _computeBlameLoaderClass(isImageDiff) {
       return !isImageDiff ? 'show' : '';
-    },
+    }
 
     _getRevisionInfo(change) {
       return new Gerrit.RevisionInfo(change);
-    },
+    }
 
     _computeFileNum(file, files) {
       // Polymer 2: check for undefined
@@ -1108,7 +1116,7 @@
       }
 
       return files.findIndex(({value}) => value === file) + 1;
-    },
+    }
 
     /**
      * @param {number} fileNum
@@ -1120,16 +1128,16 @@
         return 'show';
       }
       return '';
-    },
+    }
 
     _handleExpandAllDiffContext(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
       this.$.diffHost.expandAllContext();
-    },
+    }
 
     _computeDiffPrefsDisabled(disableDiffPrefs, loggedIn) {
       return disableDiffPrefs || !loggedIn;
-    },
+    }
 
     _handleNextUnreviewedFile(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -1138,12 +1146,14 @@
       // so we resolve the right "next" file.
       const unreviewedFiles = this._fileList
           .filter(file =>
-          (file === this._path || !this._reviewedFiles.has(file)));
+            (file === this._path || !this._reviewedFiles.has(file)));
       this._navToFile(this._path, unreviewedFiles, 1);
-    },
+    }
 
     _handleReloadingDiffPreference() {
       this._getDiffPreferences();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffView.is, GrDiffView);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
index 6427844..3a5c0bc 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff-view/gr-diff-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -269,28 +269,28 @@
       assert.isTrue(element._loading);
       assert(diffNavStub.lastCall.calledWithExactly(element._change,
           'wheatley.md', '10', '5'),
-          'Should navigate to /c/42/5..10/wheatley.md');
+      'Should navigate to /c/42/5..10/wheatley.md');
       element._path = 'wheatley.md';
 
       MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
       assert.isTrue(element._loading);
       assert(diffNavStub.lastCall.calledWithExactly(element._change,
           'glados.txt', '10', '5'),
-          'Should navigate to /c/42/5..10/glados.txt');
+      'Should navigate to /c/42/5..10/glados.txt');
       element._path = 'glados.txt';
 
       MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
       assert.isTrue(element._loading);
       assert(diffNavStub.lastCall.calledWithExactly(element._change, 'chell.go',
           '10', '5'),
-          'Should navigate to /c/42/5..10/chell.go');
+      'Should navigate to /c/42/5..10/chell.go');
       element._path = 'chell.go';
 
       MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
       assert.isTrue(element._loading);
       assert(changeNavStub.lastCall.calledWithExactly(element._change, '10',
           '5'),
-          'Should navigate to /c/42/5..10');
+      'Should navigate to /c/42/5..10');
     });
 
     test('keyboard shortcuts with old patch number', () => {
@@ -332,13 +332,13 @@
       MockInteractions.pressAndReleaseKeyOn(element, 221, null, ']');
       assert(diffNavStub.lastCall.calledWithExactly(element._change,
           'wheatley.md', '1', PARENT),
-          'Should navigate to /c/42/1/wheatley.md');
+      'Should navigate to /c/42/1/wheatley.md');
       element._path = 'wheatley.md';
 
       MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
       assert(diffNavStub.lastCall.calledWithExactly(element._change,
           'glados.txt', '1', PARENT),
-          'Should navigate to /c/42/1/glados.txt');
+      'Should navigate to /c/42/1/glados.txt');
       element._path = 'glados.txt';
 
       MockInteractions.pressAndReleaseKeyOn(element, 219, null, '[');
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group.js b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group.js
index 02ca7e5..6bd4f55 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group.js
@@ -79,7 +79,6 @@
     DELTA: 'delta',
   };
 
-
   /**
    * Hides lines in the given range behind a context control group.
    *
@@ -185,11 +184,11 @@
 
       if (before.length) {
         beforeGroups.push(before.length === group.lines.length ?
-            group : group.cloneWithLines(before));
+          group : group.cloneWithLines(before));
       }
       if (after.length) {
         afterGroups.push(after.length === group.lines.length ?
-            group : group.cloneWithLines(after));
+          group : group.cloneWithLines(after));
       }
     }
     return [beforeGroups, afterGroups];
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group_test.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group_test.html
index 16e8036..686410c 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff-group_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-group</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/web-component-tester/browser.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
index aa69248..1446fd4 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.html
@@ -294,13 +294,16 @@
         display: none;
       }
       .lineNum.COVERED {
-         background-color: #E0F2F1;
+         background-color: var(--coverage-covered, #e0f2f1);
       }
       .lineNum.NOT_COVERED {
-        background-color: #FFD1A4;
+        background-color: var(--coverage-not-covered, #ffd1a4);
       }
       .lineNum.PARTIALLY_COVERED {
-        background: linear-gradient(to right bottom, #FFD1A4 0%, #FFD1A4 50%, #E0F2F1 50%, #E0F2F1 100%);
+        background: linear-gradient(to right bottom, var(--coverage-not-covered, #ffd1a4) 0%,
+                                                     var(--coverage-not-covered, #ffd1a4) 50%,
+                                                     var(--coverage-covered, #e0f2f1) 50%,
+                                                     var(--coverage-covered, #e0f2f1) 100%);
       }
 
       /** BEGIN: Select and copy for Polymer 2 */
@@ -344,8 +347,12 @@
         text-align: center;
       }
     </style>
-    <style include="gr-syntax-theme"></style>
-    <style include="gr-ranged-comment-theme"></style>
+    <style include="gr-syntax-theme">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-ranged-comment-theme">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div id="diffHeader" hidden$="[[_computeDiffHeaderHidden(_diffHeaderItems)]]">
       <template
           is="dom-repeat"
@@ -370,7 +377,6 @@
               change-num="[[changeNum]]"
               patch-num="[[patchRange.patchNum]]"
               view-mode="[[viewMode]]"
-              line-wrapping="[[lineWrapping]]"
               is-image-diff="[[isImageDiff]]"
               base-image="[[baseImage]]"
               layers="[[layers]]"
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
index fc3862b..727115b 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff.js
@@ -91,9 +91,17 @@
 
   const RENDER_DIFF_TABLE_DEBOUNCE_NAME = 'renderDiffTable';
 
-  Polymer({
-    is: 'gr-diff',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  class GrDiff extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-diff'; }
     /**
      * Fired when the user selects a line.
      * @event line-selected
@@ -118,89 +126,98 @@
      * @event render
      */
 
-    properties: {
-      changeNum: String,
-      noAutoRender: {
-        type: Boolean,
-        value: false,
-      },
-      /** @type {?} */
-      patchRange: Object,
-      path: {
-        type: String,
-        observer: '_pathObserver',
-      },
-      prefs: {
-        type: Object,
-        observer: '_prefsObserver',
-      },
-      projectName: String,
-      displayLine: {
-        type: Boolean,
-        value: false,
-      },
-      isImageDiff: {
-        type: Boolean,
-      },
-      commitRange: Object,
-      hidden: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-      noRenderOnPrefsChange: Boolean,
-      /** @type {!Array<!Gerrit.HoveredRange>} */
-      _commentRanges: {
-        type: Array,
-        value: () => [],
-      },
-      /** @type {!Array<!Gerrit.CoverageRange>} */
-      coverageRanges: {
-        type: Array,
-        value: () => [],
-      },
-      lineWrapping: {
-        type: Boolean,
-        value: false,
-        observer: '_lineWrappingObserver',
-      },
-      viewMode: {
-        type: String,
-        value: DiffViewMode.SIDE_BY_SIDE,
-        observer: '_viewModeObserver',
-      },
+    /**
+     * Fired for interaction reporting when a diff context is expanded.
+     * Contains an event.detail with numLines about the number of lines that
+     * were expanded.
+     *
+     * @event diff-context-expanded
+     */
 
-       /** @type ?Gerrit.LineOfInterest */
-      lineOfInterest: Object,
+    static get properties() {
+      return {
+        changeNum: String,
+        noAutoRender: {
+          type: Boolean,
+          value: false,
+        },
+        /** @type {?} */
+        patchRange: Object,
+        path: {
+          type: String,
+          observer: '_pathObserver',
+        },
+        prefs: {
+          type: Object,
+          observer: '_prefsObserver',
+        },
+        projectName: String,
+        displayLine: {
+          type: Boolean,
+          value: false,
+        },
+        isImageDiff: {
+          type: Boolean,
+        },
+        commitRange: Object,
+        hidden: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+        noRenderOnPrefsChange: Boolean,
+        /** @type {!Array<!Gerrit.HoveredRange>} */
+        _commentRanges: {
+          type: Array,
+          value: () => [],
+        },
+        /** @type {!Array<!Gerrit.CoverageRange>} */
+        coverageRanges: {
+          type: Array,
+          value: () => [],
+        },
+        lineWrapping: {
+          type: Boolean,
+          value: false,
+          observer: '_lineWrappingObserver',
+        },
+        viewMode: {
+          type: String,
+          value: DiffViewMode.SIDE_BY_SIDE,
+          observer: '_viewModeObserver',
+        },
 
-      loading: {
-        type: Boolean,
-        value: false,
-        observer: '_loadingChanged',
-      },
+        /** @type ?Gerrit.LineOfInterest */
+        lineOfInterest: Object,
 
-      loggedIn: {
-        type: Boolean,
-        value: false,
-      },
-      diff: {
-        type: Object,
-        observer: '_diffChanged',
-      },
-      _diffHeaderItems: {
-        type: Array,
-        value: [],
-        computed: '_computeDiffHeaderItems(diff.*)',
-      },
-      _diffTableClass: {
-        type: String,
-        value: '',
-      },
-      /** @type {?Object} */
-      baseImage: Object,
-      /** @type {?Object} */
-      revisionImage: Object,
+        loading: {
+          type: Boolean,
+          value: false,
+          observer: '_loadingChanged',
+        },
 
-      /**
+        loggedIn: {
+          type: Boolean,
+          value: false,
+        },
+        diff: {
+          type: Object,
+          observer: '_diffChanged',
+        },
+        _diffHeaderItems: {
+          type: Array,
+          value: [],
+          computed: '_computeDiffHeaderItems(diff.*)',
+        },
+        _diffTableClass: {
+          type: String,
+          value: '',
+        },
+        /** @type {?Object} */
+        baseImage: Object,
+        /** @type {?Object} */
+        revisionImage: Object,
+
+        /**
        * Whether the safety check for large diffs when whole-file is set has
        * been bypassed. If the value is null, then the safety has not been
        * bypassed. If the value is a number, then that number represents the
@@ -208,83 +225,86 @@
        *
        * @type (number|null)
        */
-      _safetyBypass: {
-        type: Number,
-        value: null,
-      },
+        _safetyBypass: {
+          type: Number,
+          value: null,
+        },
 
-      _showWarning: Boolean,
+        _showWarning: Boolean,
 
-      /** @type {?string} */
-      errorMessage: {
-        type: String,
-        value: null,
-      },
+        /** @type {?string} */
+        errorMessage: {
+          type: String,
+          value: null,
+        },
 
-      /** @type {?Object} */
-      blame: {
-        type: Object,
-        value: null,
-        observer: '_blameChanged',
-      },
+        /** @type {?Object} */
+        blame: {
+          type: Object,
+          value: null,
+          observer: '_blameChanged',
+        },
 
-      parentIndex: Number,
+        parentIndex: Number,
 
-      _newlineWarning: {
-        type: String,
-        computed: '_computeNewlineWarning(diff)',
-      },
+        _newlineWarning: {
+          type: String,
+          computed: '_computeNewlineWarning(diff)',
+        },
 
-      _diffLength: Number,
+        _diffLength: Number,
 
-      /**
+        /**
        * Observes comment nodes added or removed after the initial render.
        * Can be used to unregister when the entire diff is (re-)rendered or upon
        * detachment.
        * @type {?PolymerDomApi.ObserveHandle}
        */
-      _incrementalNodeObserver: Object,
+        _incrementalNodeObserver: Object,
 
-      /**
+        /**
        * Observes comment nodes added or removed at any point.
        * Can be used to unregister upon detachment.
        * @type {?PolymerDomApi.ObserveHandle}
        */
-      _nodeObserver: Object,
+        _nodeObserver: Object,
 
-      /** Set by Polymer. */
-      isAttached: Boolean,
-      layers: Array,
-    },
+        /** Set by Polymer. */
+        isAttached: Boolean,
+        layers: Array,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PatchSetBehavior,
-    ],
+    static get observers() {
+      return [
+        '_enableSelectionObserver(loggedIn, isAttached)',
+      ];
+    }
 
-    listeners: {
-      'create-range-comment': '_handleCreateRangeComment',
-      'render-content': '_handleRenderContent',
-    },
-
-    observers: [
-      '_enableSelectionObserver(loggedIn, isAttached)',
-    ],
+    created() {
+      super.created();
+      this.addEventListener('create-range-comment',
+          e => this._handleCreateRangeComment(e));
+      this.addEventListener('render-content',
+          () => this._handleRenderContent());
+    }
 
     attached() {
+      super.attached();
       this._observeNodes();
-    },
+    }
 
     detached() {
+      super.detached();
       this._unobserveIncrementalNodes();
       this._unobserveNodes();
-    },
+    }
 
     showNoChangeMessage(loading, prefs, diffLength) {
       return !loading &&
         prefs && prefs.ignore_whitespace !== 'IGNORE_NONE'
         && diffLength === 0;
-    },
+    }
 
     _enableSelectionObserver(loggedIn, isAttached) {
       // Polymer 2: check for undefined
@@ -299,7 +319,7 @@
         this.unlisten(document, 'selectionchange', '_handleSelectionChange');
         this.unlisten(document, 'mouseup', '_handleMouseUp');
       }
-    },
+    }
 
     _handleSelectionChange() {
       // Because of shadow DOM selections, we handle the selectionchange here,
@@ -307,7 +327,7 @@
       // corresponding range is determined and normalized.
       const selection = this._getShadowOrDocumentSelection();
       this.$.highlights.handleSelectionChange(selection, false);
-    },
+    }
 
     _handleMouseUp(e) {
       // To handle double-click outside of text creating comments, we check on
@@ -315,7 +335,7 @@
       // can't do that on selection change since the user may still be dragging.
       const selection = this._getShadowOrDocumentSelection();
       this.$.highlights.handleSelectionChange(selection, true);
-    },
+    }
 
     /** Gets the current selection, preferring the shadow DOM selection. */
     _getShadowOrDocumentSelection() {
@@ -324,9 +344,9 @@
       // up the diff, because they are in the shadow DOM of the gr-diff element.
       // This takes the shadow DOM selection if one exists.
       return this.root.getSelection ?
-          this.root.getSelection() :
-          document.getSelection();
-    },
+        this.root.getSelection() :
+        document.getSelection();
+    }
 
     _observeNodes() {
       this._nodeObserver = Polymer.dom(this).observeNodes(info => {
@@ -335,7 +355,7 @@
         this._updateRanges(addedThreadEls, removedThreadEls);
         this._redispatchHoverEvents(addedThreadEls);
       });
-    },
+    }
 
     _updateRanges(addedThreadEls, removedThreadEls) {
       function commentRangeFromThreadEl(threadEl) {
@@ -361,7 +381,7 @@
       if (addedCommentRanges && addedCommentRanges.length) {
         this.push('_commentRanges', ...addedCommentRanges);
       }
-    },
+    }
 
     /**
      * The key locations based on the comments and line of interests,
@@ -392,7 +412,7 @@
         }
       }
       return keyLocations;
-    },
+    }
 
     // Dispatch events that are handled by the gr-diff-highlight.
     _redispatchHoverEvents(addedThreadEls) {
@@ -406,13 +426,13 @@
               'comment-thread-mouseleave', {bubbles: true, composed: true}));
         });
       }
-    },
+    }
 
     /** Cancel any remaining diff builder rendering work. */
     cancel() {
       this.$.diffBuilder.cancel();
       this.cancelDebouncer(RENDER_DIFF_TABLE_DEBOUNCE_NAME);
-    },
+    }
 
     /** @return {!Array<!HTMLElement>} */
     getCursorStops() {
@@ -422,16 +442,16 @@
 
       return Array.from(
           Polymer.dom(this.root).querySelectorAll('.diff-row'));
-    },
+    }
 
     /** @return {boolean} */
     isRangeSelected() {
-      return this.$.highlights.isRangeSelected();
-    },
+      return !!this.$.highlights.selectedRange;
+    }
 
     toggleLeftDiff() {
       this.toggleClass('no-left');
-    },
+    }
 
     _blameChanged(newValue) {
       this.$.diffBuilder.setBlame(newValue);
@@ -440,7 +460,7 @@
       } else {
         this.classList.remove('showBlame');
       }
-    },
+    }
 
     /** @return {string} */
     _computeContainerClass(loggedIn, viewMode, displayLine) {
@@ -465,12 +485,15 @@
         classes.push('displayLine');
       }
       return classes.join(' ');
-    },
+    }
 
     _handleTap(e) {
       const el = Polymer.dom(e).localTarget;
 
       if (el.classList.contains('showContext')) {
+        this.fire('diff-context-expanded', {
+          numLines: e.detail.numLines,
+        });
         this.$.diffBuilder.showContext(e.detail.groups, e.detail.section);
       } else if (el.classList.contains('lineNum')) {
         this.addDraftAtLine(el);
@@ -480,7 +503,7 @@
         const target = this.$.diffBuilder.getLineElByChild(el);
         if (target) { this._selectLine(target); }
       }
-    },
+    }
 
     _selectLine(el) {
       this.fire('line-selected', {
@@ -488,7 +511,7 @@
         number: el.getAttribute('data-value'),
         path: this.path,
       });
-    },
+    }
 
     addDraftAtLine(el) {
       this._selectLine(el);
@@ -504,18 +527,29 @@
         }
       }
       this._createComment(el, lineNum);
-    },
+    }
+
+    createRangeComment() {
+      if (!this.isRangeSelected()) {
+        throw Error('Selection is needed for new range comment');
+      }
+      const {side, range} = this.$.highlights.selectedRange;
+      this._createCommentForSelection(side, range);
+    }
+
+    _createCommentForSelection(side, range) {
+      const lineNum = range.end_line;
+      const lineEl = this.$.diffBuilder.getLineElByNumber(lineNum, side);
+      if (this._isValidElForComment(lineEl)) {
+        this._createComment(lineEl, lineNum, side, range);
+      }
+    }
 
     _handleCreateRangeComment(e) {
       const range = e.detail.range;
       const side = e.detail.side;
-      const lineNum = range.end_line;
-      const lineEl = this.$.diffBuilder.getLineElByNumber(lineNum, side);
-
-      if (this._isValidElForComment(lineEl)) {
-        this._createComment(lineEl, lineNum, side, range);
-      }
-    },
+      this._createCommentForSelection(side, range);
+    }
 
     /** @return {boolean} */
     _isValidElForComment(el) {
@@ -524,8 +558,8 @@
         return false;
       }
       const patchNum = el.classList.contains(DiffSide.LEFT) ?
-          this.patchRange.basePatchNum :
-          this.patchRange.patchNum;
+        this.patchRange.basePatchNum :
+        this.patchRange.patchNum;
 
       const isEdit = this.patchNumEquals(patchNum, this.EDIT_NAME);
       const isEditBase = this.patchNumEquals(patchNum, this.PARENT_NAME) &&
@@ -539,7 +573,7 @@
         return false;
       }
       return true;
-    },
+    }
 
     /**
      * @param {!Object} lineEl
@@ -567,11 +601,11 @@
           range,
         },
       }));
-    },
+    }
 
     _getThreadGroupForLine(contentEl) {
       return contentEl.querySelector('.thread-group');
-    },
+    }
 
     /**
      * Gets or creates a comment thread group for a specific line and side on a
@@ -590,7 +624,7 @@
         contentEl.appendChild(threadGroupEl);
       }
       return threadGroupEl;
-    },
+    }
 
     /**
      * The value to be used for the patch number of new comments created at the
@@ -616,7 +650,7 @@
         patchNum = this.patchRange.basePatchNum;
       }
       return patchNum;
-    },
+    }
 
     /** @return {boolean} */
     _getIsParentCommentByLineAndContent(lineEl, contentEl) {
@@ -627,7 +661,7 @@
         return true;
       }
       return false;
-    },
+    }
 
     /** @return {string} */
     _getCommentSideByLineAndContent(lineEl, contentEl) {
@@ -637,7 +671,7 @@
         side = 'left';
       }
       return side;
-    },
+    }
 
     _prefsObserver(newPrefs, oldPrefs) {
       // Scan the preference objects one level deep to see if they differ.
@@ -653,16 +687,16 @@
       if (differ) {
         this._prefsChanged(newPrefs);
       }
-    },
+    }
 
     _pathObserver() {
       // Call _prefsChanged(), because line-limit style value depends on path.
       this._prefsChanged(this.prefs);
-    },
+    }
 
     _viewModeObserver() {
       this._prefsChanged(this.prefs);
-    },
+    }
 
     /** @param {boolean} newValue */
     _loadingChanged(newValue) {
@@ -673,11 +707,11 @@
         this._showWarning = false;
         this.clearDiffContent();
       }
-    },
+    }
 
     _lineWrappingObserver() {
       this._prefsChanged(this.prefs);
-    },
+    }
 
     _prefsChanged(prefs) {
       if (!prefs) { return; }
@@ -708,14 +742,14 @@
       if (this.diff && !this.noRenderOnPrefsChange) {
         this._debounceRenderDiffTable();
       }
-    },
+    }
 
     _diffChanged(newValue) {
       if (newValue) {
         this._diffLength = this.getDiffLength(newValue);
         this._debounceRenderDiffTable();
       }
-    },
+    }
 
     /**
      * When called multiple times from the same microtask, will call
@@ -730,7 +764,7 @@
     _debounceRenderDiffTable() {
       this.debounce(
           RENDER_DIFF_TABLE_DEBOUNCE_NAME, () => this._renderDiffTable());
-    },
+    }
 
     _renderDiffTable() {
       this._unobserveIncrementalNodes();
@@ -760,7 +794,7 @@
                   detail: {contentRendered: true},
                 }));
           });
-    },
+    }
 
     _handleRenderContent() {
       this._incrementalNodeObserver = Polymer.dom(this).observeNodes(info => {
@@ -799,19 +833,19 @@
           lastEl.replaceWith(lastEl);
         }
       });
-    },
+    }
 
     _unobserveIncrementalNodes() {
       if (this._incrementalNodeObserver) {
         Polymer.dom(this).unobserveNodes(this._incrementalNodeObserver);
       }
-    },
+    }
 
     _unobserveNodes() {
       if (this._nodeObserver) {
         Polymer.dom(this).unobserveNodes(this._nodeObserver);
       }
-    },
+    }
 
     /**
      * Get the preferences object including the safety bypass context (if any).
@@ -821,12 +855,12 @@
         return Object.assign({}, this.prefs, {context: this._safetyBypass});
       }
       return this.prefs;
-    },
+    }
 
     clearDiffContent() {
       this._unobserveIncrementalNodes();
       this.$.diffTable.innerHTML = null;
-    },
+    }
 
     /** @return {!Array} */
     _computeDiffHeaderItems(diffInfoRecord) {
@@ -839,27 +873,27 @@
             item.startsWith('--- ') ||
             item === 'Binary files differ');
       });
-    },
+    }
 
     /** @return {boolean} */
     _computeDiffHeaderHidden(items) {
       return items.length === 0;
-    },
+    }
 
     _handleFullBypass() {
       this._safetyBypass = FULL_CONTEXT;
       this._debounceRenderDiffTable();
-    },
+    }
 
     _handleLimitedBypass() {
       this._safetyBypass = LIMITED_CONTEXT;
       this._debounceRenderDiffTable();
-    },
+    }
 
     /** @return {string} */
     _computeWarningClass(showWarning) {
       return showWarning ? 'warn' : '';
-    },
+    }
 
     /**
      * @param {string} errorMessage
@@ -867,11 +901,11 @@
      */
     _computeErrorClass(errorMessage) {
       return errorMessage ? 'showError' : '';
-    },
+    }
 
     expandAllContext() {
       this._handleFullBypass();
-    },
+    }
 
     /**
      * Find the last chunk for the given side.
@@ -892,8 +926,8 @@
         chunkIndex--;
         chunk = diff.content[chunkIndex];
       } while (
-          // We haven't reached the beginning.
-          chunkIndex >= 0 &&
+      // We haven't reached the beginning.
+        chunkIndex >= 0 &&
 
           // The chunk doesn't have both sides.
           !chunk.ab &&
@@ -907,7 +941,7 @@
       if (chunkIndex === -1) { return null; }
 
       return chunk;
-    },
+    }
 
     /**
      * Check whether the specified side of the diff has a trailing newline.
@@ -928,7 +962,7 @@
         lines = leftSide ? chunk.a : chunk.b;
       }
       return lines[lines.length - 1] === '';
-    },
+    }
 
     /**
      * @param {!Object} diff
@@ -946,7 +980,7 @@
       }
       if (!messages.length) { return null; }
       return messages.join(' — ');
-    },
+    }
 
     /**
      * @param {string} warning
@@ -956,7 +990,7 @@
     _computeNewlineWarningClass(warning, loading) {
       if (loading || !warning) { return 'newlineWarning hidden'; }
       return 'newlineWarning';
-    },
+    }
 
     /**
      * Get the approximate length of the diff as the sum of the maximum
@@ -975,6 +1009,8 @@
               sec.hasOwnProperty('b') ? sec.b.length : 0);
         }
       }, 0);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiff.is, GrDiff);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff_test.html b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff_test.html
index 09342e1..2805eb4 100644
--- a/polygerrit-ui/app/elements/diff/gr-diff/gr-diff_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-diff/gr-diff_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -76,7 +76,6 @@
       });
     });
 
-
     test('cancel', () => {
       element = fixture('basic');
       const cancelStub = sandbox.stub(element.$.diffBuilder, 'cancel');
@@ -868,7 +867,6 @@
           assert.isNull(element._lastChunkForSide(diff, true));
         });
 
-
         test('deletion with b undefined', () => {
           const diff = {content: [
             {a: ['foo', 'bar', 'baz']},
@@ -1070,7 +1068,7 @@
             /* loading= */ false,
             element.prefs,
             element._diffLength
-          ));
+        ));
       });
 
       test('do not show the message if still loading', () => {
@@ -1079,7 +1077,7 @@
             /* loading= */ true,
             element.prefs,
             element._diffLength
-          ));
+        ));
       });
 
       test('do not show the message if contains valid changes', () => {
@@ -1098,7 +1096,7 @@
             /* loading= */ false,
             element.prefs,
             element._diffLength
-          ));
+        ));
       });
 
       test('do not show message if ignore whitespace is disabled', () => {
@@ -1116,7 +1114,7 @@
             /* loading= */ false,
             element.prefs,
             element._diffLength
-          ));
+        ));
       });
     });
 
@@ -1129,7 +1127,7 @@
       element = fixture('basic');
       element.prefs = {};
       renderStub = sandbox.stub(element.$.diffBuilder, 'render')
-            .returns(Promise.resolve());
+          .returns(Promise.resolve());
       element.addEventListener('render', event => {
         assert.isTrue(event.detail.contentRendered);
         done();
diff --git a/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select.js b/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select.js
index cdc5f30..14148a9 100644
--- a/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select.js
+++ b/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select.js
@@ -21,6 +21,9 @@
   const PATCH_DESC_MAX_LENGTH = 500;
 
   /**
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  /**
    * Fired when the patch range changes
    *
    * @event patch-range-change
@@ -28,42 +31,47 @@
    * @property {string} patchNum
    * @property {string} basePatchNum
    */
+  class GrPatchRangeSelect extends Polymer.mixinBehaviors( [
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-patch-range-select'; }
 
-  Polymer({
-    is: 'gr-patch-range-select',
-
-    properties: {
-      availablePatches: Array,
-      _baseDropdownContent: {
-        type: Object,
-        computed: '_computeBaseDropdownContent(availablePatches, patchNum,' +
+    static get properties() {
+      return {
+        availablePatches: Array,
+        _baseDropdownContent: {
+          type: Object,
+          computed: '_computeBaseDropdownContent(availablePatches, patchNum,' +
             '_sortedRevisions, changeComments, revisionInfo)',
-      },
-      _patchDropdownContent: {
-        type: Object,
-        computed: '_computePatchDropdownContent(availablePatches,' +
+        },
+        _patchDropdownContent: {
+          type: Object,
+          computed: '_computePatchDropdownContent(availablePatches,' +
             'basePatchNum, _sortedRevisions, changeComments)',
-      },
-      changeNum: String,
-      changeComments: Object,
-      /** @type {{ meta_a: !Array, meta_b: !Array}} */
-      filesWeblinks: Object,
-      patchNum: String,
-      basePatchNum: String,
-      revisions: Object,
-      revisionInfo: Object,
-      _sortedRevisions: Array,
-    },
+        },
+        changeNum: String,
+        changeComments: Object,
+        /** @type {{ meta_a: !Array, meta_b: !Array}} */
+        filesWeblinks: Object,
+        patchNum: String,
+        basePatchNum: String,
+        revisions: Object,
+        revisionInfo: Object,
+        _sortedRevisions: Array,
+      };
+    }
 
-    observers: [
-      '_updateSortedRevisions(revisions.*)',
-    ],
-
-    behaviors: [Gerrit.PatchSetBehavior],
+    static get observers() {
+      return [
+        '_updateSortedRevisions(revisions.*)',
+      ];
+    }
 
     _getShaForPatch(patch) {
       return patch.sha.substring(0, 10);
-    },
+    }
 
     _computeBaseDropdownContent(availablePatches, patchNum, _sortedRevisions,
         changeComments, revisionInfo) {
@@ -80,7 +88,7 @@
 
       const parentCounts = revisionInfo.getParentCountMap();
       const currentParentCount = parentCounts.hasOwnProperty(patchNum) ?
-          parentCounts[patchNum] : 1;
+        parentCounts[patchNum] : 1;
       const maxParents = revisionInfo.getMaxParents();
       const isMerge = currentParentCount > 1;
 
@@ -111,13 +119,13 @@
       }
 
       return dropdownContent;
-    },
+    }
 
     _computeMobileText(patchNum, changeComments, revisions) {
       return `${patchNum}` +
           `${this._computePatchSetCommentsString(changeComments, patchNum)}` +
           `${this._computePatchSetDescription(revisions, patchNum, true)}`;
-    },
+    }
 
     _computePatchDropdownContent(availablePatches, basePatchNum,
         _sortedRevisions, changeComments) {
@@ -143,13 +151,13 @@
         }));
       }
       return dropdownContent;
-    },
+    }
 
     _computeText(patchNum, prefix, changeComments, sha) {
       return `${prefix}${patchNum}` +
         `${this._computePatchSetCommentsString(changeComments, patchNum)}`
           + (` | ${sha}`);
-    },
+    }
 
     _createDropdownEntry(patchNum, prefix, sortedRevisions, changeComments,
         sha) {
@@ -167,12 +175,12 @@
         entry['date'] = date;
       }
       return entry;
-    },
+    }
 
     _updateSortedRevisions(revisionsRecord) {
       const revisions = revisionsRecord.base;
       this._sortedRevisions = this.sortRevisions(Object.values(revisions));
-    },
+    }
 
     /**
      * The basePatchNum should always be <= patchNum -- because sortedRevisions
@@ -185,7 +193,7 @@
     _computeLeftDisabled(basePatchNum, patchNum, sortedRevisions) {
       return this.findSortedIndex(basePatchNum, sortedRevisions) <=
           this.findSortedIndex(patchNum, sortedRevisions);
-    },
+    }
 
     /**
      * The basePatchNum should always be <= patchNum -- because sortedRevisions
@@ -214,8 +222,7 @@
 
       return this.findSortedIndex(basePatchNum, sortedRevisions) <=
           this.findSortedIndex(patchNum, sortedRevisions);
-    },
-
+    }
 
     _computePatchSetCommentsString(changeComments, patchNum) {
       if (!changeComments) { return; }
@@ -236,7 +243,7 @@
           // Add a comma + space if both comments and unresolved
           (commentString && unresolvedString ? ', ' : '') +
           `${unresolvedString})`;
-    },
+    }
 
     /**
      * @param {!Array} revisions
@@ -246,9 +253,9 @@
     _computePatchSetDescription(revisions, patchNum, opt_addFrontSpace) {
       const rev = this.getRevisionByPatchNum(revisions, patchNum);
       return (rev && rev.description) ?
-          (opt_addFrontSpace ? ' ' : '') +
+        (opt_addFrontSpace ? ' ' : '') +
           rev.description.substring(0, PATCH_DESC_MAX_LENGTH) : '';
-    },
+    }
 
     /**
      * @param {!Array} revisions
@@ -257,7 +264,7 @@
     _computePatchSetDate(revisions, patchNum) {
       const rev = this.getRevisionByPatchNum(revisions, patchNum);
       return rev ? rev.created : undefined;
-    },
+    }
 
     /**
      * Catches value-change events from the patchset dropdowns and determines
@@ -275,6 +282,8 @@
 
       this.dispatchEvent(
           new CustomEvent('patch-range-change', {detail, bubbles: false}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPatchRangeSelect.is, GrPatchRangeSelect);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select_test.html b/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select_test.html
index 66fa974..81897cd 100644
--- a/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-patch-range-select/gr-patch-range-select_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-patch-range-select</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -185,7 +185,7 @@
       assert.deepEqual(element._computeBaseDropdownContent(availablePatches,
           patchNum, sortedRevisions, element.changeComments,
           element.revisionInfo),
-          expectedResult);
+      expectedResult);
     });
 
     test('_computeBaseDropdownContent called when patchNum updates', () => {
@@ -344,7 +344,7 @@
 
       assert.deepEqual(element._computePatchDropdownContent(availablePatches,
           basePatchNum, sortedRevisions, element.changeComments),
-          expectedResult);
+      expectedResult);
     });
 
     test('filesWeblinks', () => {
diff --git a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
index c7c9b9d..7ee6492 100644
--- a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
+++ b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer.js
@@ -23,9 +23,10 @@
   const RANGE_HIGHLIGHT = 'style-scope gr-diff range';
   const HOVER_HIGHLIGHT = 'style-scope gr-diff rangeHighlight';
 
-  Polymer({
-    is: 'gr-ranged-comment-layer',
-
+  class GrRangedCommentLayer extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-ranged-comment-layer'; }
     /**
      * Fired when the range in a range comment was malformed and had to be
      * normalized.
@@ -35,26 +36,30 @@
      * @event normalize-range
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {!Array<!Gerrit.HoveredRange>} */
-      commentRanges: Array,
-      _listeners: {
-        type: Array,
-        value() { return []; },
-      },
-      _rangesMap: {
-        type: Object,
-        value() { return {left: {}, right: {}}; },
-      },
-    },
+        commentRanges: Array,
+        _listeners: {
+          type: Array,
+          value() { return []; },
+        },
+        _rangesMap: {
+          type: Object,
+          value() { return {left: {}, right: {}}; },
+        },
+      };
+    }
 
-    observers: [
-      '_handleCommentRangesChange(commentRanges.*)',
-    ],
+    static get observers() {
+      return [
+        '_handleCommentRangesChange(commentRanges.*)',
+      ];
+    }
 
     get styleModuleName() {
       return 'gr-ranged-comment-styles';
-    },
+    }
 
     /**
      * Layer method to add annotations to a line.
@@ -66,12 +71,12 @@
     annotate(el, lineNumberEl, line) {
       let ranges = [];
       if (line.type === GrDiffLine.Type.REMOVE || (
-          line.type === GrDiffLine.Type.BOTH &&
+        line.type === GrDiffLine.Type.BOTH &&
           el.getAttribute('data-side') !== 'right')) {
         ranges = ranges.concat(this._getRangesForLine(line, 'left'));
       }
       if (line.type === GrDiffLine.Type.ADD || (
-          line.type === GrDiffLine.Type.BOTH &&
+        line.type === GrDiffLine.Type.BOTH &&
           el.getAttribute('data-side') !== 'left')) {
         ranges = ranges.concat(this._getRangesForLine(line, 'right'));
       }
@@ -81,7 +86,7 @@
             range.end - range.start,
             range.hovering ? HOVER_HIGHLIGHT : RANGE_HIGHLIGHT);
       }
-    },
+    }
 
     /**
      * Register a listener for layer updates.
@@ -91,7 +96,7 @@
      */
     addListener(fn) {
       this._listeners.push(fn);
-    },
+    }
 
     /**
      * Notify Layer listeners of changes to annotations.
@@ -103,7 +108,7 @@
       for (const listener of this._listeners) {
         listener(start, end, side);
       }
-    },
+    }
 
     /**
      * Handle change in the ranges by updating the ranges maps and by
@@ -134,7 +139,7 @@
         this._updateRangesMap(
             side, range, hovering, (forLine, start, end, hovering) => {
               const index = forLine.findIndex(lineRange =>
-                  lineRange.start === start && lineRange.end === end);
+                lineRange.start === start && lineRange.end === end);
               forLine[index].hovering = hovering;
             });
       }
@@ -147,7 +152,7 @@
             this._updateRangesMap(
                 side, range, hovering, (forLine, start, end) => {
                   const index = forLine.findIndex(lineRange =>
-                      lineRange.start === start && lineRange.end === end);
+                    lineRange.start === start && lineRange.end === end);
                   forLine.splice(index, 1);
                 });
           }
@@ -161,7 +166,7 @@
           }
         }
       }
-    },
+    }
 
     _updateRangesMap(side, range, hovering, operation) {
       const forSide = this._rangesMap[side] || (this._rangesMap[side] = {});
@@ -172,7 +177,7 @@
         operation(forLine, start, end, hovering);
       }
       this._notifyUpdateRange(range.start_line, range.end_line, side);
-    },
+    }
 
     _getRangesForLine(line, side) {
       const lineNum = side === 'left' ? line.beforeNumber : line.afterNumber;
@@ -200,6 +205,8 @@
           })
           // Sort the ranges so that hovering highlights are on top.
           .sort((a, b) => a.hovering && !b.hovering ? 1 : 0);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRangedCommentLayer.is, GrRangedCommentLayer);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
index 9d207a5..4ed744b 100644
--- a/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-ranged-comment-layer/gr-ranged-comment-layer_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-ranged-comment-layer</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.js b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.js
index b1b3e0f..3ef9105 100644
--- a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.js
+++ b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box.js
@@ -17,48 +17,38 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-selection-action-box',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrSelectionActionBox extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-selection-action-box'; }
     /**
-     * Fired when the comment creation action was taken (hotkey, click).
+     * Fired when the comment creation action was taken (click).
      *
-     * @event create-range-comment
+     * @event create-comment-requested
      */
 
-    properties: {
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      range: {
-        type: Object,
-        value: {
-          start_line: NaN,
-          start_character: NaN,
-          end_line: NaN,
-          end_character: NaN,
+    static get properties() {
+      return {
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
         },
-      },
-      positionBelow: Boolean,
-      side: {
-        type: String,
-        value: '',
-      },
-    },
+        positionBelow: Boolean,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
+    created() {
+      super.created();
 
-    listeners: {
-      mousedown: '_handleMouseDown', // See https://crbug.com/gerrit/4767
-    },
-
-    keyBindings: {
-      c: '_handleCKey',
-    },
+      // See https://crbug.com/gerrit/4767
+      this.addEventListener('mousedown',
+          e => this._handleMouseDown(e));
+    }
 
     placeAbove(el) {
       Polymer.dom.flush();
@@ -69,7 +59,7 @@
           rect.top - parentRect.top - boxRect.height - 6 + 'px';
       this.style.left =
           rect.left - parentRect.left + (rect.width - boxRect.width) / 2 + 'px';
-    },
+    }
 
     placeBelow(el) {
       Polymer.dom.flush();
@@ -80,14 +70,14 @@
       rect.top - parentRect.top + boxRect.height - 6 + 'px';
       this.style.left =
       rect.left - parentRect.left + (rect.width - boxRect.width) / 2 + 'px';
-    },
+    }
 
     _getParentBoundingClientRect() {
       // With native shadow DOM, the parent is the shadow root, not the gr-diff
       // element
       const parent = this.parentElement || this.parentNode.host;
       return parent.getBoundingClientRect();
-    },
+    }
 
     _getTargetBoundingRect(el) {
       let rect;
@@ -100,25 +90,15 @@
         rect = el.getBoundingClientRect();
       }
       return rect;
-    },
-
-    _handleCKey(e) {
-      if (this.shouldSuppressKeyboardShortcut(e) ||
-          this.modifierPressed(e)) { return; }
-
-      e.preventDefault();
-      this._fireCreateComment();
-    },
+    }
 
     _handleMouseDown(e) {
       if (e.button !== 0) { return; } // 0 = main button
       e.preventDefault();
       e.stopPropagation();
-      this._fireCreateComment();
-    },
+      this.fire('create-comment-requested');
+    }
+  }
 
-    _fireCreateComment() {
-      this.fire('create-range-comment', {side: this.side, range: this.range});
-    },
-  });
+  customElements.define(GrSelectionActionBox.is, GrSelectionActionBox);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box_test.html b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box_test.html
index b950e7b..57adf32 100644
--- a/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-selection-action-box/gr-selection-action-box_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-selection-action-box</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -59,11 +59,6 @@
       assert.isFalse(element.fire.called);
     });
 
-    test('reacts to hotkey', () => {
-      MockInteractions.pressAndReleaseKeyOn(document.body, 67, null, 'c');
-      assert.isTrue(element.fire.called);
-    });
-
     suite('mousedown reacts only to main button', () => {
       let e;
 
@@ -73,40 +68,22 @@
           preventDefault: sandbox.stub(),
           stopPropagation: sandbox.stub(),
         };
-        sandbox.stub(element, '_fireCreateComment');
       });
 
       test('event handled if main button', () => {
         element._handleMouseDown(e);
         assert.isTrue(e.preventDefault.called);
+        assert(element.fire.calledWithExactly('create-comment-requested'));
       });
 
       test('event ignored if not main button', () => {
         e.button = 1;
         element._handleMouseDown(e);
         assert.isFalse(e.preventDefault.called);
+        assert.isFalse(element.fire.called);
       });
     });
 
-    test('event fired contains playload', () => {
-      const side = 'left';
-      const range = {
-        start_line: 1,
-        start_character: 11,
-        end_line: 2,
-        end_character: 42,
-      };
-      element.side = 'left';
-      element.range = range;
-      MockInteractions.pressAndReleaseKeyOn(document.body, 67, null, 'c');
-      assert(element.fire.calledWithExactly(
-          'create-range-comment',
-          {
-            side,
-            range,
-          }));
-    });
-
     suite('placeAbove', () => {
       let target;
 
diff --git a/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer.js b/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer.js
index 3151a12..8ef946c 100644
--- a/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer.js
+++ b/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer.js
@@ -131,54 +131,58 @@
   const GO_BACKSLASH_LITERAL = '\'\\\\\'';
   const GLOBAL_LT_PATTERN = /</g;
 
-  Polymer({
-    is: 'gr-syntax-layer',
+  class GrSyntaxLayer extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-syntax-layer'; }
 
-    properties: {
-      diff: {
-        type: Object,
-        observer: '_diffChanged',
-      },
-      enabled: {
-        type: Boolean,
-        value: true,
-      },
-      _baseRanges: {
-        type: Array,
-        value() { return []; },
-      },
-      _revisionRanges: {
-        type: Array,
-        value() { return []; },
-      },
-      _baseLanguage: String,
-      _revisionLanguage: String,
-      _listeners: {
-        type: Array,
-        value() { return []; },
-      },
-      /** @type {?number} */
-      _processHandle: Number,
-      /**
+    static get properties() {
+      return {
+        diff: {
+          type: Object,
+          observer: '_diffChanged',
+        },
+        enabled: {
+          type: Boolean,
+          value: true,
+        },
+        _baseRanges: {
+          type: Array,
+          value() { return []; },
+        },
+        _revisionRanges: {
+          type: Array,
+          value() { return []; },
+        },
+        _baseLanguage: String,
+        _revisionLanguage: String,
+        _listeners: {
+          type: Array,
+          value() { return []; },
+        },
+        /** @type {?number} */
+        _processHandle: Number,
+        /**
        * The promise last returned from `process()` while the asynchronous
        * processing is running - `null` otherwise. Provides a `cancel()`
        * method that rejects it with `{isCancelled: true}`.
        * @type {?Object}
        */
-      _processPromise: {
-        type: Object,
-        value: null,
-      },
-      _hljs: Object,
-    },
+        _processPromise: {
+          type: Object,
+          value: null,
+        },
+        _hljs: Object,
+      };
+    }
 
     addListener(fn) {
       this.push('_listeners', fn);
-    },
+    }
 
     removeListener(fn) {
       this._listeners = this._listeners.filter(f => f != fn);
-    },
+    }
 
     /**
      * Annotation layer method to add syntax annotations to the given element
@@ -193,11 +197,11 @@
       // Determine the side.
       let side;
       if (line.type === GrDiffLine.Type.REMOVE || (
-          line.type === GrDiffLine.Type.BOTH &&
+        line.type === GrDiffLine.Type.BOTH &&
           el.getAttribute('data-side') !== 'right')) {
         side = 'left';
       } else if (line.type === GrDiffLine.Type.ADD || (
-          el.getAttribute('data-side') !== 'left')) {
+        el.getAttribute('data-side') !== 'left')) {
         side = 'right';
       }
 
@@ -215,14 +219,14 @@
         GrAnnotation.annotateElement(
             el, range.start, range.length, range.className);
       }
-    },
+    }
 
     _getLanguage(diffFileMetaInfo) {
       // The Gerrit API provides only content-type, but for other users of
       // gr-diff it may be more convenient to specify the language directly.
       return diffFileMetaInfo.language ||
           LANGUAGE_MAP[diffFileMetaInfo.content_type];
-    },
+    }
 
     /**
      * Start processing syntax for the loaded diff and notify layer listeners
@@ -261,12 +265,14 @@
         lastNotify: {left: 1, right: 1},
       };
 
+      const rangesCache = new Map();
+
       this._processPromise = util.makeCancelable(this._loadHLJS()
           .then(() => {
             return new Promise(resolve => {
               const nextStep = () => {
                 this._processHandle = null;
-                this._processNextLine(state);
+                this._processNextLine(state, rangesCache);
 
                 // Move to the next line in the section.
                 state.lineIndex++;
@@ -297,7 +303,7 @@
           }));
       return this._processPromise
           .finally(() => { this._processPromise = null; });
-    },
+    }
 
     /**
      * Cancel any asynchronous syntax processing jobs.
@@ -310,26 +316,35 @@
       if (this._processPromise) {
         this._processPromise.cancel();
       }
-    },
+    }
 
     _diffChanged() {
       this._cancel();
       this._baseRanges = [];
       this._revisionRanges = [];
-    },
+    }
 
     /**
      * Take a string of HTML with the (potentially nested) syntax markers
      * Highlight.js emits and emit a list of text ranges and classes for the
      * markers.
      * @param {string} str The string of HTML.
+     * @param {Map<string, !Array<!Object>>} rangesCache A map for caching
+     * ranges for each string. A cache is read and written by this method.
+     * Since diff is mostly comparing same file on two sides, there is good rate
+     * of duplication at least for parts that are on left and right parts.
      * @return {!Array<!Object>} The list of ranges.
      */
-    _rangesFromString(str) {
+    _rangesFromString(str, rangesCache) {
+      const cached = rangesCache.get(str);
+      if (cached) return cached;
+
       const div = document.createElement('div');
       div.innerHTML = str;
-      return this._rangesFromElement(div, 0);
-    },
+      const ranges = this._rangesFromElement(div, 0);
+      rangesCache.set(str, ranges);
+      return ranges;
+    }
 
     _rangesFromElement(elem, offset) {
       let result = [];
@@ -352,14 +367,14 @@
         offset += nodeLength;
       }
       return result;
-    },
+    }
 
     /**
      * For a given state, process the syntax for the next line (or pair of
      * lines).
      * @param {!Object} state The processing state for the layer.
      */
-    _processNextLine(state) {
+    _processNextLine(state, rangesCache) {
       let baseLine;
       let revisionLine;
 
@@ -388,7 +403,8 @@
         baseLine = this._workaround(this._baseLanguage, baseLine);
         result = this._hljs.highlight(this._baseLanguage, baseLine, true,
             state.baseContext);
-        this.push('_baseRanges', this._rangesFromString(result.value));
+        this.push('_baseRanges',
+            this._rangesFromString(result.value, rangesCache));
         state.baseContext = result.top;
       }
 
@@ -397,10 +413,11 @@
         revisionLine = this._workaround(this._revisionLanguage, revisionLine);
         result = this._hljs.highlight(this._revisionLanguage, revisionLine,
             true, state.revisionContext);
-        this.push('_revisionRanges', this._rangesFromString(result.value));
+        this.push('_revisionRanges',
+            this._rangesFromString(result.value, rangesCache));
         state.revisionContext = result.top;
       }
-    },
+    }
 
     /**
      * Ad hoc fixes for HLJS parsing bugs. Rewrite lines of code in constrained
@@ -467,7 +484,7 @@
       }
 
       return line;
-    },
+    }
 
     /**
      * Tells whether the state has exhausted its current section.
@@ -482,7 +499,7 @@
         return (!section.a || state.lineIndex >= section.a.length) &&
             (!section.b || state.lineIndex >= section.b.length);
       }
-    },
+    }
 
     /**
      * For a given state, notify layer listeners of any processed line ranges
@@ -504,18 +521,20 @@
             'right');
         state.lastNotify.right = state.lineNums.right;
       }
-    },
+    }
 
     _notifyRange(start, end, side) {
       for (const fn of this._listeners) {
         fn(start, end, side);
       }
-    },
+    }
 
     _loadHLJS() {
       return this.$.libLoader.getHLJS().then(hljs => {
         this._hljs = hljs;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSyntaxLayer.is, GrSyntaxLayer);
 })();
diff --git a/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer_test.html b/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer_test.html
index 472db21..926a6bc 100644
--- a/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer_test.html
+++ b/polygerrit-ui/app/elements/diff/gr-syntax-layer/gr-syntax-layer_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-syntax-layer</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -388,10 +388,20 @@
         '<span class="non-whtelisted-class">',
         '<span class="gr-diff gr-syntax gr-syntax-keyword">public</span>',
         '</span>'].join('');
-      const result = element._rangesFromString(str);
+      const result = element._rangesFromString(str, new Map());
       assert.notEqual(result.length, 0);
     });
 
+    test('_rangesFromString cache same syntax markers', () => {
+      sandbox.spy(element, '_rangesFromElement');
+      const str =
+        '<span class="gr-diff gr-syntax gr-syntax-keyword">public</span>';
+      const cacheMap = new Map();
+      element._rangesFromString(str, cacheMap);
+      element._rangesFromString(str, cacheMap);
+      assert.isTrue(element._rangesFromElement.calledOnce);
+    });
+
     test('_isSectionDone', () => {
       let state = {sectionIndex: 0, lineIndex: 0};
       assert.isFalse(element._isSectionDone(state));
diff --git a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.html b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.html
index 5072b9d..5ae679e 100644
--- a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.html
+++ b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.html
@@ -25,8 +25,12 @@
 
 <dom-module id="gr-documentation-search">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-table-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-table-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <gr-list-view
         filter="[[_filter]]"
         items=false
diff --git a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.js b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.js
index f850b9d..779b16f 100644
--- a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.js
+++ b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search.js
@@ -17,50 +17,56 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-documentation-search',
+  /**
+    * @appliesMixin Gerrit.ListViewMixin
+    */
+  class GrDocumentationSearch extends Polymer.mixinBehaviors( [
+    Gerrit.ListViewBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-documentation-search'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
 
-      _path: {
-        type: String,
-        readOnly: true,
-        value: '/Documentation',
-      },
-      _documentationSearches: Array,
+        _path: {
+          type: String,
+          readOnly: true,
+          value: '/Documentation',
+        },
+        _documentationSearches: Array,
 
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _filter: {
-        type: String,
-        value: '',
-      },
-    },
-
-    behaviors: [
-      Gerrit.ListViewBehavior,
-    ],
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _filter: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this.dispatchEvent(
           new CustomEvent('title-change', {title: 'Documentation Search'}));
-    },
+    }
 
     _paramsChanged(params) {
       this._loading = true;
       this._filter = this.getFilterValue(params);
 
       return this._getDocumentationSearches(this._filter);
-    },
+    }
 
     _getDocumentationSearches(filter) {
       this._documentationSearches = [];
@@ -71,11 +77,13 @@
             this._documentationSearches = searches;
             this._loading = false;
           });
-    },
+    }
 
     _computeSearchUrl(url) {
       if (!url) { return ''; }
       return this.getBaseUrl() + '/' + url;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDocumentationSearch.is, GrDocumentationSearch);
 })();
diff --git a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search_test.html b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search_test.html
index 84298e2..688a9e6 100644
--- a/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search_test.html
+++ b/polygerrit-ui/app/elements/documentation/gr-documentation-search/gr-documentation-search_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-documentation-search</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor.js b/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor.js
index ed96bb2..ce9db61 100644
--- a/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor.js
+++ b/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor.js
@@ -17,23 +17,28 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-default-editor',
-
+  class GrDefaultEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-default-editor'; }
     /**
      * Fired when the content of the editor changes.
      *
      * @event content-change
      */
 
-    properties: {
-      fileContent: String,
-    },
+    static get properties() {
+      return {
+        fileContent: String,
+      };
+    }
 
     _handleTextareaInput(e) {
       this.dispatchEvent(new CustomEvent(
           'content-change',
           {detail: {value: e.target.value}, bubbles: true, composed: true}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDefaultEditor.is, GrDefaultEditor);
 })();
diff --git a/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor_test.html b/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor_test.html
index c986e7c..4635b1c 100644
--- a/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor_test.html
+++ b/polygerrit-ui/app/elements/edit/gr-default-editor/gr-default-editor_test.html
@@ -17,7 +17,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-default-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-constants.html b/polygerrit-ui/app/elements/edit/gr-edit-constants.html
index d526ccd..5895124 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-constants.html
+++ b/polygerrit-ui/app/elements/edit/gr-edit-constants.html
@@ -22,7 +22,7 @@
 
     // Order corresponds to order in the UI.
     GrEditConstants.Actions = {
-      OPEN: {label: 'Open', id: 'open'},
+      OPEN: {label: 'Add/Open', id: 'open'},
       DELETE: {label: 'Delete', id: 'delete'},
       RENAME: {label: 'Rename', id: 'rename'},
       RESTORE: {label: 'Restore', id: 'restore'},
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.html b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.html
index 52692a7..cb950da 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.html
+++ b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.html
@@ -55,21 +55,13 @@
       gr-dialog .main > iron-input{
         width: 100%;
       }
-      gr-autocomplete {
-        --gr-autocomplete: {
-          border: 1px solid var(--border-color);
-          border-radius: var(--border-radius);
-          height: 2em;
-          padding: 0 var(--spacing-xs);
-        }
-      }
       input {
         border: 1px solid var(--border-color);
         border-radius: var(--border-radius);
-        height: 2em;
         margin: var(--spacing-m) 0;
-        padding: 0 var(--spacing-xs);
+        padding: var(--spacing-s);
         width: 100%;
+        box-sizing: content-box;
       }
       @media screen and (max-width: 50em) {
         gr-dialog {
@@ -89,12 +81,12 @@
           id="openDialog"
           class="invisible dialog"
           disabled$="[[!_isValidPath(_path)]]"
-          confirm-label="Open"
+          confirm-label="Confirm"
           confirm-on-enter
           on-confirm="_handleOpenConfirm"
           on-cancel="_handleDialogCancel">
         <div class="header" slot="header">
-          Open an existing or new file
+          Add a new file or open an existing file
         </div>
         <div class="main" slot="main">
           <gr-autocomplete
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
index 5aed3e4..6a585e1 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
+++ b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls.js
@@ -17,47 +17,52 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-edit-controls',
+  /**
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  class GrEditControls extends Polymer.mixinBehaviors( [
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-edit-controls'; }
 
-    properties: {
-      change: Object,
-      patchNum: String,
+    static get properties() {
+      return {
+        change: Object,
+        patchNum: String,
 
-      /**
+        /**
        * TODO(kaspern): by default, the RESTORE action should be hidden in the
        * file-list as it is a per-file action only. Remove this default value
        * when the Actions dictionary is moved to a shared constants file and
        * use the hiddenActions property in the parent component.
        */
-      hiddenActions: {
-        type: Array,
-        value() { return [GrEditConstants.Actions.RESTORE.id]; },
-      },
-
-      _actions: {
-        type: Array,
-        value() { return Object.values(GrEditConstants.Actions); },
-      },
-      _path: {
-        type: String,
-        value: '',
-      },
-      _newPath: {
-        type: String,
-        value: '',
-      },
-      _query: {
-        type: Function,
-        value() {
-          return this._queryFiles.bind(this);
+        hiddenActions: {
+          type: Array,
+          value() { return [GrEditConstants.Actions.RESTORE.id]; },
         },
-      },
-    },
 
-    behaviors: [
-      Gerrit.PatchSetBehavior,
-    ],
+        _actions: {
+          type: Array,
+          value() { return Object.values(GrEditConstants.Actions); },
+        },
+        _path: {
+          type: String,
+          value: '',
+        },
+        _newPath: {
+          type: String,
+          value: '',
+        },
+        _query: {
+          type: Function,
+          value() {
+            return this._queryFiles.bind(this);
+          },
+        },
+      };
+    }
 
     _handleTap(e) {
       e.preventDefault();
@@ -76,7 +81,7 @@
           this.openRestoreDialog();
           return;
       }
-    },
+    }
 
     /**
      * @param {string=} opt_path
@@ -84,7 +89,7 @@
     openOpenDialog(opt_path) {
       if (opt_path) { this._path = opt_path; }
       return this._showDialog(this.$.openDialog);
-    },
+    }
 
     /**
      * @param {string=} opt_path
@@ -92,7 +97,7 @@
     openDeleteDialog(opt_path) {
       if (opt_path) { this._path = opt_path; }
       return this._showDialog(this.$.deleteDialog);
-    },
+    }
 
     /**
      * @param {string=} opt_path
@@ -100,7 +105,7 @@
     openRenameDialog(opt_path) {
       if (opt_path) { this._path = opt_path; }
       return this._showDialog(this.$.renameDialog);
-    },
+    }
 
     /**
      * @param {string=} opt_path
@@ -108,7 +113,7 @@
     openRestoreDialog(opt_path) {
       if (opt_path) { this._path = opt_path; }
       return this._showDialog(this.$.restoreDialog);
-    },
+    }
 
     /**
      * Given a path string, checks that it is a valid file path.
@@ -118,11 +123,11 @@
     _isValidPath(path) {
       // Double negation needed for strict boolean return type.
       return !!path.length && !path.endsWith('/');
-    },
+    }
 
     _computeRenameDisabled(path, newPath) {
       return this._isValidPath(path) && this._isValidPath(newPath);
-    },
+    }
 
     /**
      * Given a dom event, gets the dialog that lies along this event path.
@@ -134,7 +139,7 @@
         if (!element.classList) { return false; }
         return element.classList.contains('dialog');
       });
-    },
+    }
 
     _showDialog(dialog) {
       // Some dialogs may not fire their on-close event when closed in certain
@@ -148,12 +153,12 @@
         if (autocomplete) { autocomplete.focus(); }
         this.async(() => { this.$.overlay.center(); }, 1);
       });
-    },
+    }
 
     _hideAllDialogs() {
       const dialogs = Polymer.dom(this.root).querySelectorAll('.dialog');
       for (const dialog of dialogs) { this._closeDialog(dialog); }
-    },
+    }
 
     /**
      * @param {Element|undefined} dialog
@@ -175,18 +180,18 @@
 
       dialog.classList.toggle('invisible', true);
       return this.$.overlay.close();
-    },
+    }
 
     _handleDialogCancel(e) {
       this._closeDialog(this._getDialogFromEvent(e));
-    },
+    }
 
     _handleOpenConfirm(e) {
       const url = Gerrit.Nav.getEditUrlForDiff(this.change, this._path,
           this.patchNum);
       Gerrit.Nav.navigateToRelativeUrl(url);
       this._closeDialog(this._getDialogFromEvent(e), true);
-    },
+    }
 
     _handleDeleteConfirm(e) {
       // Get the dialog before the api call as the event will change during bubbling
@@ -198,7 +203,7 @@
             this._closeDialog(dialog, true);
             Gerrit.Nav.navigateToChange(this.change);
           });
-    },
+    }
 
     _handleRestoreConfirm(e) {
       const dialog = this._getDialogFromEvent(e);
@@ -208,27 +213,29 @@
             this._closeDialog(dialog, true);
             Gerrit.Nav.navigateToChange(this.change);
           });
-    },
+    }
 
     _handleRenameConfirm(e) {
       const dialog = this._getDialogFromEvent(e);
       return this.$.restAPI.renameFileInChangeEdit(this.change._number,
           this._path, this._newPath).then(res => {
-            if (!res.ok) { return; }
-            this._closeDialog(dialog, true);
-            Gerrit.Nav.navigateToChange(this.change);
-          });
-    },
+        if (!res.ok) { return; }
+        this._closeDialog(dialog, true);
+        Gerrit.Nav.navigateToChange(this.change);
+      });
+    }
 
     _queryFiles(input) {
       return this.$.restAPI.queryChangeFiles(this.change._number,
           this.patchNum, input).then(res => res.map(file => {
-            return {name: file};
-          }));
-    },
+        return {name: file};
+      }));
+    }
 
     _computeIsInvisible(id, hiddenActions) {
       return hiddenActions.includes(id) ? 'invisible' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditControls.is, GrEditControls);
 })();
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls_test.html b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls_test.html
index df029ed..2d7dc9c 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls_test.html
+++ b/polygerrit-ui/app/elements/edit/gr-edit-controls/gr-edit-controls_test.html
@@ -17,7 +17,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-edit-controls</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -192,8 +192,8 @@
     let renameStub;
     let renameAutocomplete;
     const inputSelector = Polymer.Element ?
-        '.newPathIronInput' :
-        '.newPathInput';
+      '.newPathIronInput' :
+      '.newPathInput';
 
     setup(() => {
       navStub = sandbox.stub(Gerrit.Nav, 'navigateToChange');
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls.js b/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls.js
index 250816b..ddd2d29 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls.js
+++ b/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls.js
@@ -17,38 +17,41 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-edit-file-controls',
-
+  class GrEditFileControls extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-edit-file-controls'; }
     /**
      * Fired when an action in the overflow menu is tapped.
      *
      * @event file-action-tap
      */
 
-    properties: {
-      filePath: String,
-      _allFileActions: {
-        type: Array,
-        value: () => Object.values(GrEditConstants.Actions),
-      },
-      _fileActions: {
-        type: Array,
-        computed: '_computeFileActions(_allFileActions)',
-      },
-    },
+    static get properties() {
+      return {
+        filePath: String,
+        _allFileActions: {
+          type: Array,
+          value: () => Object.values(GrEditConstants.Actions),
+        },
+        _fileActions: {
+          type: Array,
+          computed: '_computeFileActions(_allFileActions)',
+        },
+      };
+    }
 
     _handleActionTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this._dispatchFileAction(e.detail.id, this.filePath);
-    },
+    }
 
     _dispatchFileAction(action, path) {
       this.dispatchEvent(new CustomEvent(
           'file-action-tap',
           {detail: {action, path}, bubbles: true, composed: true}));
-    },
+    }
 
     _computeFileActions(actions) {
       // TODO(kaspern): conditionally disable some actions based on file status.
@@ -58,6 +61,8 @@
           id: action.id,
         };
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditFileControls.is, GrEditFileControls);
 })();
diff --git a/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls_test.html b/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls_test.html
index 7979e57..dc26468 100644
--- a/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls_test.html
+++ b/polygerrit-ui/app/elements/edit/gr-edit-file-controls/gr-edit-file-controls_test.html
@@ -17,7 +17,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-edit-file-controls</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.js b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.js
index 95cfaf6..ab50921 100644
--- a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.js
+++ b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view.js
@@ -24,9 +24,21 @@
 
   const STORAGE_DEBOUNCE_INTERVAL_MS = 100;
 
-  Polymer({
-    is: 'gr-editor-view',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.PathListMixin
+    */
+  class GrEditorView extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.PathListBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-editor-view'; }
     /**
      * Fired when the title of the page should change.
      *
@@ -39,69 +51,69 @@
      * @event show-alert
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * URL params passed from the router.
        */
-      params: {
-        type: Object,
-        observer: '_paramsChanged',
-      },
+        params: {
+          type: Object,
+          observer: '_paramsChanged',
+        },
 
-      _change: Object,
-      _changeEditDetail: Object,
-      _changeNum: String,
-      _patchNum: String,
-      _path: String,
-      _type: String,
-      _content: String,
-      _newContent: String,
-      _saving: {
-        type: Boolean,
-        value: false,
-      },
-      _successfulSave: {
-        type: Boolean,
-        value: false,
-      },
-      _saveDisabled: {
-        type: Boolean,
-        value: true,
-        computed: '_computeSaveDisabled(_content, _newContent, _saving)',
-      },
-      _prefs: Object,
-    },
+        _change: Object,
+        _changeEditDetail: Object,
+        _changeNum: String,
+        _patchNum: String,
+        _path: String,
+        _type: String,
+        _content: String,
+        _newContent: String,
+        _saving: {
+          type: Boolean,
+          value: false,
+        },
+        _successfulSave: {
+          type: Boolean,
+          value: false,
+        },
+        _saveDisabled: {
+          type: Boolean,
+          value: true,
+          computed: '_computeSaveDisabled(_content, _newContent, _saving)',
+        },
+        _prefs: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.PathListBehavior,
-    ],
+    get keyBindings() {
+      return {
+        'ctrl+s meta+s': '_handleSaveShortcut',
+      };
+    }
 
-    listeners: {
-      'content-change': '_handleContentChange',
-    },
-
-    keyBindings: {
-      'ctrl+s meta+s': '_handleSaveShortcut',
-    },
+    created() {
+      super.created();
+      this.addEventListener('content-change',
+          e => this._handleContentChange(e));
+    }
 
     attached() {
+      super.attached();
       this._getEditPrefs().then(prefs => { this._prefs = prefs; });
-    },
+    }
 
     get storageKey() {
       return `c${this._changeNum}_ps${this._patchNum}_${this._path}`;
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _getEditPrefs() {
       return this.$.restAPI.getEditPreferences();
-    },
+    }
 
     _paramsChanged(value) {
       if (value.view !== Gerrit.Nav.View.EDIT) {
@@ -126,13 +138,13 @@
       promises.push(
           this._getFileData(this._changeNum, this._path, this._patchNum));
       return Promise.all(promises);
-    },
+    }
 
     _getChangeDetail(changeNum) {
       return this.$.restAPI.getDiffChangeDetail(changeNum).then(change => {
         this._change = change;
       });
-    },
+    }
 
     _handlePathChanged(e) {
       const path = e.detail;
@@ -141,18 +153,18 @@
       }
       return this.$.restAPI.renameFileInChangeEdit(this._changeNum,
           this._path, path).then(res => {
-            if (!res.ok) { return; }
+        if (!res.ok) { return; }
 
-            this._successfulSave = true;
-            this._viewEditInChangeView();
-          });
-    },
+        this._successfulSave = true;
+        this._viewEditInChangeView();
+      });
+    }
 
     _viewEditInChangeView() {
       const patch = this._successfulSave ? this.EDIT_NAME : this._patchNum;
       Gerrit.Nav.navigateToChange(this._change, patch, null,
           patch !== this.EDIT_NAME);
-    },
+    }
 
     _getFileData(changeNum, path, patchNum) {
       const storedContent =
@@ -183,7 +195,7 @@
               this._type = '';
             }
           });
-    },
+    }
 
     _saveEdit() {
       this._saving = true;
@@ -191,14 +203,14 @@
       this.$.storage.eraseEditableContentItem(this.storageKey);
       return this.$.restAPI.saveChangeEdit(this._changeNum, this._path,
           this._newContent).then(res => {
-            this._saving = false;
-            this._showAlert(res.ok ? SAVED_MESSAGE : SAVE_FAILED_MSG);
-            if (!res.ok) { return; }
+        this._saving = false;
+        this._showAlert(res.ok ? SAVED_MESSAGE : SAVE_FAILED_MSG);
+        if (!res.ok) { return; }
 
-            this._content = this._newContent;
-            this._successfulSave = true;
-          });
-    },
+        this._content = this._newContent;
+        this._successfulSave = true;
+      });
+    }
 
     _showAlert(message) {
       this.dispatchEvent(new CustomEvent('show-alert', {
@@ -206,7 +218,7 @@
         bubbles: true,
         composed: true,
       }));
-    },
+    }
 
     _computeSaveDisabled(content, newContent, saving) {
       // Polymer 2: check for undefined
@@ -222,12 +234,12 @@
         return true;
       }
       return content === newContent;
-    },
+    }
 
     _handleCloseTap() {
       // TODO(kaspern): Add a confirm dialog if there are unsaved changes.
       this._viewEditInChangeView();
-    },
+    }
 
     _handleContentChange(e) {
       this.debounce('store', () => {
@@ -239,13 +251,15 @@
           this.$.storage.eraseEditableContentItem(this.storageKey);
         }
       }, STORAGE_DEBOUNCE_INTERVAL_MS);
-    },
+    }
 
     _handleSaveShortcut(e) {
       e.preventDefault();
       if (!this._saveDisabled) {
         this._saveEdit();
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditorView.is, GrEditorView);
 })();
diff --git a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.html b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.html
index abb8131..ebd624e 100644
--- a/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.html
+++ b/polygerrit-ui/app/elements/edit/gr-editor-view/gr-editor-view_test.html
@@ -17,7 +17,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-editor-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -106,7 +106,7 @@
     // Calling with the same path should not navigate.
     return element._handlePathChanged({detail: mockParams.path}).then(() => {
       assert.isFalse(savePathStub.called);
-        // !ok response
+      // !ok response
       element._handlePathChanged({detail: 'newPath'}).then(() => {
         assert.isTrue(savePathStub.called);
         assert.isFalse(navigateStub.called);
diff --git a/polygerrit-ui/app/elements/gr-app-element.html b/polygerrit-ui/app/elements/gr-app-element.html
index 046e5ff..f758280 100644
--- a/polygerrit-ui/app/elements/gr-app-element.html
+++ b/polygerrit-ui/app/elements/gr-app-element.html
@@ -211,7 +211,6 @@
     </footer>
     <gr-overlay id="keyboardShortcuts" with-backdrop>
       <gr-keyboard-shortcuts-dialog
-          view="[[params.view]]"
           on-close="_handleKeyboardShortcutDialogClose"></gr-keyboard-shortcuts-dialog>
     </gr-overlay>
     <gr-overlay id="registrationOverlay" with-backdrop>
diff --git a/polygerrit-ui/app/elements/gr-app-element.js b/polygerrit-ui/app/elements/gr-app-element.js
index d5d944a..1e86acc 100644
--- a/polygerrit-ui/app/elements/gr-app-element.js
+++ b/polygerrit-ui/app/elements/gr-app-element.js
@@ -17,90 +17,90 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-app-element',
-
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrAppElement extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-app-element'; }
     /**
      * Fired when the URL location changes.
      *
      * @event location-change
      */
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * @type {{ query: string, view: string, screen: string }}
        */
-      params: Object,
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
+        params: Object,
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
 
-      _account: {
-        type: Object,
-        observer: '_accountChanged',
-      },
+        _account: {
+          type: Object,
+          observer: '_accountChanged',
+        },
 
-      /**
+        /**
        * The last time the g key was pressed in milliseconds (or a keydown event
        * was handled if the key is held down).
        * @type {number|null}
        */
-      _lastGKeyPressTimestamp: {
-        type: Number,
-        value: null,
-      },
+        _lastGKeyPressTimestamp: {
+          type: Number,
+          value: null,
+        },
 
-      /**
+        /**
        * @type {{ plugin: Object }}
        */
-      _serverConfig: Object,
-      _version: String,
-      _showChangeListView: Boolean,
-      _showDashboardView: Boolean,
-      _showChangeView: Boolean,
-      _showDiffView: Boolean,
-      _showSettingsView: Boolean,
-      _showAdminView: Boolean,
-      _showCLAView: Boolean,
-      _showEditorView: Boolean,
-      _showPluginScreen: Boolean,
-      _showDocumentationSearch: Boolean,
-      /** @type {?} */
-      _viewState: Object,
-      /** @type {?} */
-      _lastError: Object,
-      _lastSearchPage: String,
-      _path: String,
-      _pluginScreenName: {
-        type: String,
-        computed: '_computePluginScreenName(params)',
-      },
-      _settingsUrl: String,
-      _feedbackUrl: String,
-      // Used to allow searching on mobile
-      mobileSearch: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _serverConfig: Object,
+        _version: String,
+        _showChangeListView: Boolean,
+        _showDashboardView: Boolean,
+        _showChangeView: Boolean,
+        _showDiffView: Boolean,
+        _showSettingsView: Boolean,
+        _showAdminView: Boolean,
+        _showCLAView: Boolean,
+        _showEditorView: Boolean,
+        _showPluginScreen: Boolean,
+        _showDocumentationSearch: Boolean,
+        /** @type {?} */
+        _viewState: Object,
+        /** @type {?} */
+        _lastError: Object,
+        _lastSearchPage: String,
+        _path: String,
+        _pluginScreenName: {
+          type: String,
+          computed: '_computePluginScreenName(params)',
+        },
+        _settingsUrl: String,
+        _feedbackUrl: String,
+        // Used to allow searching on mobile
+        mobileSearch: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    listeners: {
-      'page-error': '_handlePageError',
-      'title-change': '_handleTitleChange',
-      'location-change': '_handleLocationChange',
-      'rpc-log': '_handleRpcLog',
-    },
-
-    observers: [
-      '_viewChanged(params.view)',
-      '_paramsChanged(params.*)',
-    ],
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
+    static get observers() {
+      return [
+        '_viewChanged(params.view)',
+        '_paramsChanged(params.*)',
+      ];
+    }
 
     keyboardShortcuts() {
       return {
@@ -111,14 +111,24 @@
         [this.Shortcut.GO_TO_ABANDONED_CHANGES]: '_goToAbandonedChanges',
         [this.Shortcut.GO_TO_WATCHED_CHANGES]: '_goToWatchedChanges',
       };
-    },
+    }
 
     created() {
+      super.created();
       this._bindKeyboardShortcuts();
-    },
+      this.addEventListener('page-error',
+          e => this._handlePageError(e));
+      this.addEventListener('title-change',
+          e => this._handleTitleChange(e));
+      this.addEventListener('location-change',
+          e => this._handleLocationChange(e));
+      this.addEventListener('rpc-log',
+          e => this._handleRpcLog(e));
+    }
 
     ready() {
-      this.$.reporting.appStarted(document.visibilityState === 'hidden');
+      super.ready();
+      this.$.reporting.appStarted();
       this.$.router.start();
 
       this.$.restAPI.getAccount().then(account => {
@@ -165,7 +175,7 @@
           selectedChangeIndex: 0,
         },
       };
-    },
+    }
 
     _bindKeyboardShortcuts() {
       this.bindShortcut(this.Shortcut.SEND_REPLY,
@@ -201,7 +211,7 @@
       this.bindShortcut(
           this.Shortcut.TOGGLE_CHANGE_STAR, 's:keyup');
       this.bindShortcut(
-          this.Shortcut.REFRESH_CHANGE_LIST, 'shift+r');
+          this.Shortcut.REFRESH_CHANGE_LIST, 'shift+r:keyup');
       this.bindShortcut(
           this.Shortcut.EDIT_TOPIC, 't');
 
@@ -214,7 +224,7 @@
       this.bindShortcut(
           this.Shortcut.COLLAPSE_ALL_MESSAGES, 'z');
       this.bindShortcut(
-          this.Shortcut.REFRESH_CHANGE, 'shift+r');
+          this.Shortcut.REFRESH_CHANGE, 'shift+r:keyup');
       this.bindShortcut(
           this.Shortcut.UP_TO_DASHBOARD, 'u');
       this.bindShortcut(
@@ -287,7 +297,7 @@
 
       this.bindShortcut(
           this.Shortcut.SEARCH, '/');
-    },
+    }
 
     _accountChanged(account) {
       if (!account) { return; }
@@ -298,7 +308,7 @@
       this.$.restAPI.getEditPreferences();
       this.$.errorManager.knownAccountId =
           this._account && this._account._account_id || null;
-    },
+    }
 
     _viewChanged(view) {
       this.$.errorView.classList.remove('show');
@@ -328,7 +338,7 @@
         });
       }
       this.$.header.unfloat();
-    },
+    }
 
     _handlePageError(e) {
       const props = [
@@ -356,7 +366,7 @@
           this._lastError = err;
         });
       }
-    },
+    }
 
     _handleLocationChange(e) {
       const hash = e.detail.hash.substring(1);
@@ -365,7 +375,7 @@
         pathname += '@' + hash;
       }
       this.set('_path', pathname);
-    },
+    }
 
     _paramsChanged(paramsRecord) {
       const params = paramsRecord.base;
@@ -373,7 +383,7 @@
       if (viewsToCheck.includes(params.view)) {
         this.set('_lastSearchPage', location.pathname);
       }
-    },
+    }
 
     _handleTitleChange(e) {
       if (e.detail.title) {
@@ -381,54 +391,54 @@
       } else {
         document.title = '';
       }
-    },
+    }
 
     _showKeyboardShortcuts(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
       this.$.keyboardShortcuts.open();
-    },
+    }
 
     _handleKeyboardShortcutDialogClose() {
       this.$.keyboardShortcuts.close();
-    },
+    }
 
     _handleAccountDetailUpdate(e) {
       this.$.mainHeader.reload();
       if (this.params.view === Gerrit.Nav.View.SETTINGS) {
         this.$$('gr-settings-view').reloadAccountDetail();
       }
-    },
+    }
 
     _handleRegistrationDialogClose(e) {
       this.params.justRegistered = false;
       this.$.registrationOverlay.close();
-    },
+    }
 
     _goToOpenedChanges() {
       Gerrit.Nav.navigateToStatusSearch('open');
-    },
+    }
 
     _goToUserDashboard() {
       Gerrit.Nav.navigateToUserDashboard();
-    },
+    }
 
     _goToMergedChanges() {
       Gerrit.Nav.navigateToStatusSearch('merged');
-    },
+    }
 
     _goToAbandonedChanges() {
       Gerrit.Nav.navigateToStatusSearch('abandoned');
-    },
+    }
 
     _goToWatchedChanges() {
       // The query is hardcoded, and doesn't respect custom menu entries
       Gerrit.Nav.navigateToSearchQuery('is:watched is:open');
-    },
+    }
 
     _computePluginScreenName({plugin, screen}) {
       if (!plugin || !screen) return '';
       return `${plugin}-screen-${screen}`;
-    },
+    }
 
     _logWelcome() {
       console.group('Runtime Info');
@@ -441,7 +451,7 @@
         console.log(`Please file bugs and feedback at: ${this._feedbackUrl}`);
       }
       console.groupEnd();
-    },
+    }
 
     /**
      * Intercept RPC log events emitted by REST API interfaces.
@@ -451,17 +461,19 @@
     _handleRpcLog(e) {
       this.$.reporting.reportRpcTiming(e.detail.anonymizedUrl,
           e.detail.elapsed);
-    },
+    }
 
     _mobileSearchToggle(e) {
       this.mobileSearch = !this.mobileSearch;
-    },
+    }
 
     getThemeEndpoint() {
       // For now, we only have dark mode and light mode
       return window.localStorage.getItem('dark-theme') ?
         'app-theme-dark' :
         'app-theme-light';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAppElement.is, GrAppElement);
 })();
diff --git a/polygerrit-ui/app/elements/gr-app.js b/polygerrit-ui/app/elements/gr-app.js
index ac8ea1a..46a81ee 100644
--- a/polygerrit-ui/app/elements/gr-app.js
+++ b/polygerrit-ui/app/elements/gr-app.js
@@ -17,7 +17,11 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-app',
-  });
+  class GrApp extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-app'; }
+  }
+
+  customElements.define(GrApp.is, GrApp);
 })();
diff --git a/polygerrit-ui/app/elements/gr-app_test.html b/polygerrit-ui/app/elements/gr-app_test.html
index 9f1b7f8..c069f8b 100644
--- a/polygerrit-ui/app/elements/gr-app_test.html
+++ b/polygerrit-ui/app/elements/gr-app_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-app</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-admin-api/gr-admin-api_test.html b/polygerrit-ui/app/elements/plugins/gr-admin-api/gr-admin-api_test.html
index 2537a37..10ba710 100644
--- a/polygerrit-ui/app/elements/plugins/gr-admin-api/gr-admin-api_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-admin-api/gr-admin-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-admin-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-attribute-helper/gr-attribute-helper_test.html b/polygerrit-ui/app/elements/plugins/gr-attribute-helper/gr-attribute-helper_test.html
index 0c4149c..c95128b 100644
--- a/polygerrit-ui/app/elements/plugins/gr-attribute-helper/gr-attribute-helper_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-attribute-helper/gr-attribute-helper_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-attribute-helper</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js b/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js
index b550f73..0454767 100644
--- a/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js
+++ b/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js
@@ -31,7 +31,7 @@
       this._createHook();
     }
     this._hook.onAttached(element =>
-        this.plugin.attributeHelper(element).bind('labels', callback));
+      this.plugin.attributeHelper(element).bind('labels', callback));
     return this;
   };
 
diff --git a/polygerrit-ui/app/elements/plugins/gr-dom-hooks/gr-dom-hooks_test.html b/polygerrit-ui/app/elements/plugins/gr-dom-hooks/gr-dom-hooks_test.html
index 9e657fa..a00dc68 100644
--- a/polygerrit-ui/app/elements/plugins/gr-dom-hooks/gr-dom-hooks_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-dom-hooks/gr-dom-hooks_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-dom-hooks</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator.js b/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator.js
index 448e090..9942716 100644
--- a/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator.js
+++ b/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator.js
@@ -19,33 +19,38 @@
 
   const INIT_PROPERTIES_TIMEOUT_MS = 10000;
 
-  Polymer({
-    is: 'gr-endpoint-decorator',
+  class GrEndpointDecorator extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-endpoint-decorator'; }
 
-    properties: {
-      name: String,
-      /** @type {!Map} */
-      _domHooks: {
-        type: Map,
-        value() { return new Map(); },
-      },
-      /**
+    static get properties() {
+      return {
+        name: String,
+        /** @type {!Map} */
+        _domHooks: {
+          type: Map,
+          value() { return new Map(); },
+        },
+        /**
        * This map prevents importing the same endpoint twice.
        * Without caching, if a plugin is loaded after the loaded plugins
        * callback fires, it will be imported twice and appear twice on the page.
        * @type {!Map}
        */
-      _initializedPlugins: {
-        type: Map,
-        value() { return new Map(); },
-      },
-    },
+        _initializedPlugins: {
+          type: Map,
+          value() { return new Map(); },
+        },
+      };
+    }
 
     detached() {
+      super.detached();
       for (const [el, domHook] of this._domHooks) {
         domHook.handleInstanceDetached(el);
       }
-    },
+    }
 
     /**
      * @suppress {checkTypes}
@@ -54,7 +59,7 @@
       return new Promise((resolve, reject) => {
         (this.importHref || Polymer.importHref)(url, resolve, reject);
       });
-    },
+    }
 
     _initDecoration(name, plugin) {
       const el = document.createElement(name);
@@ -62,7 +67,7 @@
           this.getContentChildren().find(
               el => el.nodeName !== 'GR-ENDPOINT-PARAM'))
           .then(el => this._appendChild(el));
-    },
+    }
 
     _initReplacement(name, plugin) {
       this.getContentChildNodes()
@@ -71,12 +76,12 @@
       const el = document.createElement(name);
       return this._initProperties(el, plugin).then(
           el => this._appendChild(el));
-    },
+    }
 
     _getEndpointParams() {
       return Array.from(
           Polymer.dom(this).querySelectorAll('gr-endpoint-param'));
-    },
+    }
 
     /**
      * @param {!Element} el
@@ -95,25 +100,25 @@
         return helper.get('value').then(
             value => helper.bind('value',
                 value => plugin.attributeHelper(el).set(paramName, value))
-            );
+        );
       });
       let timeoutId;
       const timeout = new Promise(
-        resolve => timeoutId = setTimeout(() => {
-          console.warn(
-              'Timeout waiting for endpoint properties initialization: ' +
+          resolve => timeoutId = setTimeout(() => {
+            console.warn(
+                'Timeout waiting for endpoint properties initialization: ' +
               `plugin ${plugin.getPluginName()}, endpoint ${this.name}`);
-        }, INIT_PROPERTIES_TIMEOUT_MS));
+          }, INIT_PROPERTIES_TIMEOUT_MS));
       return Promise.race([timeout, Promise.all(expectProperties)])
           .then(() => {
             clearTimeout(timeoutId);
             return el;
           });
-    },
+    }
 
     _appendChild(el) {
       return Polymer.dom(this.root).appendChild(el);
-    },
+    }
 
     _initModule({moduleName, plugin, type, domHook}) {
       const name = plugin.getPluginName() + '.' + moduleName;
@@ -137,9 +142,10 @@
         domHook.handleInstanceAttached(el);
         this._domHooks.set(el, domHook);
       });
-    },
+    }
 
     ready() {
+      super.ready();
       Gerrit._endpoints.onNewEndpoint(this.name, this._initModule.bind(this));
       Gerrit.awaitPluginsLoaded().then(() => Promise.all(
           Gerrit._endpoints.getPlugins(this.name).map(
@@ -149,6 +155,8 @@
             .getDetails(this.name)
             .forEach(this._initModule, this)
       );
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEndpointDecorator.is, GrEndpointDecorator);
 })();
diff --git a/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator_test.html b/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator_test.html
index b0ad585..58e2074 100644
--- a/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-endpoint-decorator/gr-endpoint-decorator_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-endpoint-decorator</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-endpoint-param/gr-endpoint-param.js b/polygerrit-ui/app/elements/plugins/gr-endpoint-param/gr-endpoint-param.js
index c7a2d9a..3010750 100644
--- a/polygerrit-ui/app/elements/plugins/gr-endpoint-param/gr-endpoint-param.js
+++ b/polygerrit-ui/app/elements/plugins/gr-endpoint-param/gr-endpoint-param.js
@@ -17,17 +17,21 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-endpoint-param',
+  class GrEndpointParam extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-endpoint-param'; }
 
-    properties: {
-      name: String,
-      value: {
-        type: Object,
-        notify: true,
-        observer: '_valueChanged',
-      },
-    },
+    static get properties() {
+      return {
+        name: String,
+        value: {
+          type: Object,
+          notify: true,
+          observer: '_valueChanged',
+        },
+      };
+    }
 
     _valueChanged(newValue, oldValue) {
       /* In polymer 2 the following change was made:
@@ -42,6 +46,8 @@
         value: newValue,
       };
       this.dispatchEvent(new CustomEvent('value-changed', {detail}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEndpointParam.is, GrEndpointParam);
 })();
diff --git a/polygerrit-ui/app/elements/plugins/gr-event-helper/gr-event-helper_test.html b/polygerrit-ui/app/elements/plugins/gr-event-helper/gr-event-helper_test.html
index bd76bd4..a98a0d2 100644
--- a/polygerrit-ui/app/elements/plugins/gr-event-helper/gr-event-helper_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-event-helper/gr-event-helper_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-event-helper</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style.js b/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style.js
index e90ff30..aa9b13e 100644
--- a/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style.js
+++ b/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style.js
@@ -17,20 +17,24 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-external-style',
+  class GrExternalStyle extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-external-style'; }
 
-    properties: {
-      name: String,
-      _urlsImported: {
-        type: Array,
-        value() { return []; },
-      },
-      _stylesApplied: {
-        type: Array,
-        value() { return []; },
-      },
-    },
+    static get properties() {
+      return {
+        name: String,
+        _urlsImported: {
+          type: Array,
+          value() { return []; },
+        },
+        _stylesApplied: {
+          type: Array,
+          value() { return []; },
+        },
+      };
+    }
 
     /**
      * @suppress {checkTypes}
@@ -41,14 +45,13 @@
       return new Promise((resolve, reject) => {
         (this.importHref || Polymer.importHref)(url, resolve, reject);
       });
-    },
+    }
 
     _applyStyle(name) {
       if (this._stylesApplied.includes(name)) { return; }
       this._stylesApplied.push(name);
-      // Hybrid custom-style syntax:
-      // https://polymer-library.polymer-project.org/2.0/docs/devguide/style-shadow-dom
-      const s = document.createElement('style', 'custom-style');
+
+      const s = document.createElement('style');
       s.setAttribute('include', name);
       const cs = document.createElement('custom-style');
       cs.appendChild(s);
@@ -57,7 +60,7 @@
       const topEl = document.getElementsByTagName('body')[0];
       topEl.insertBefore(cs, topEl.firstChild);
       Polymer.updateStyles();
-    },
+    }
 
     _importAndApply() {
       Promise.all(Gerrit._endpoints.getPlugins(this.name).map(
@@ -68,14 +71,18 @@
           this._applyStyle(name);
         }
       });
-    },
+    }
 
     attached() {
+      super.attached();
       this._importAndApply();
-    },
+    }
 
     ready() {
+      super.ready();
       Gerrit.awaitPluginsLoaded().then(() => this._importAndApply());
-    },
-  });
+    }
+  }
+
+  customElements.define(GrExternalStyle.is, GrExternalStyle);
 })();
diff --git a/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style_test.html b/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style_test.html
index 9566067..9f0c950 100644
--- a/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-external-style/gr-external-style_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-external-style</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host.js b/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host.js
index 21da106..30adcc8 100644
--- a/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host.js
+++ b/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host.js
@@ -17,15 +17,19 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-plugin-host',
+  class GrPluginHost extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-plugin-host'; }
 
-    properties: {
-      config: {
-        type: Object,
-        observer: '_configChanged',
-      },
-    },
+    static get properties() {
+      return {
+        config: {
+          type: Object,
+          observer: '_configChanged',
+        },
+      };
+    }
 
     _configChanged(config) {
       const plugins = config.plugin;
@@ -50,7 +54,7 @@
       }
 
       Gerrit._loadPlugins(pluginsPending, pluginOpts);
-    },
+    }
 
     /**
      * Omit .js plugins that have .html counterparts.
@@ -61,6 +65,8 @@
         const counterpart = url.replace(/\.js$/, '.html');
         return !htmlPlugins.includes(counterpart);
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPluginHost.is, GrPluginHost);
 })();
diff --git a/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host_test.html b/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host_test.html
index 3a8e4d8..1f748b8 100644
--- a/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-plugin-host/gr-plugin-host_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-host</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.html b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.html
index 402d988..d084445 100644
--- a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.html
+++ b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.html
@@ -20,7 +20,9 @@
 
 <dom-module id="gr-plugin-popup">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <gr-overlay id="overlay" with-backdrop>
       <slot></slot>
     </gr-overlay>
diff --git a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.js b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.js
index 2e7a2b7..412e788a 100644
--- a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.js
+++ b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup.js
@@ -17,19 +17,23 @@
 (function(window) {
   'use strict';
 
-  Polymer({
-    is: 'gr-plugin-popup',
+  class GrPluginPopup extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-plugin-popup'; }
 
     get opened() {
       return this.$.overlay.opened;
-    },
+    }
 
     open() {
       return this.$.overlay.open();
-    },
+    }
 
     close() {
       this.$.overlay.close();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPluginPopup.is, GrPluginPopup);
 })(window);
diff --git a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup_test.html b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup_test.html
index 1f1e81e..2ff2aba 100644
--- a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-plugin-popup_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-popup</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface.js b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface.js
index 556cfd8..e3f8694 100644
--- a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface.js
+++ b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface.js
@@ -46,17 +46,17 @@
     if (!this._openingPromise) {
       this._openingPromise =
           this.plugin.hook('plugin-overlay').getLastAttached()
-      .then(hookEl => {
-        const popup = document.createElement('gr-plugin-popup');
-        if (this._moduleName) {
-          const el = Polymer.dom(popup).appendChild(
-              document.createElement(this._moduleName));
-          el.plugin = this.plugin;
-        }
-        this._popup = Polymer.dom(hookEl).appendChild(popup);
-        Polymer.dom.flush();
-        return this._popup.open().then(() => this);
-      });
+              .then(hookEl => {
+                const popup = document.createElement('gr-plugin-popup');
+                if (this._moduleName) {
+                  const el = Polymer.dom(popup).appendChild(
+                      document.createElement(this._moduleName));
+                  el.plugin = this.plugin;
+                }
+                this._popup = Polymer.dom(hookEl).appendChild(popup);
+                Polymer.dom.flush();
+                return this._popup.open().then(() => this);
+              });
     }
     return this._openingPromise;
   };
diff --git a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface_test.html b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface_test.html
index 53370e2..0be07d4 100644
--- a/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-popup-interface/gr-popup-interface_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-popup-interface</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-repo-api/gr-repo-api_test.html b/polygerrit-ui/app/elements/plugins/gr-repo-api/gr-repo-api_test.html
index 0b32f8a..5a47a85 100644
--- a/polygerrit-ui/app/elements/plugins/gr-repo-api/gr-repo-api_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-repo-api/gr-repo-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-settings-api/gr-settings-api_test.html b/polygerrit-ui/app/elements/plugins/gr-settings-api/gr-settings-api_test.html
index cbc2de6..6248d78 100644
--- a/polygerrit-ui/app/elements/plugins/gr-settings-api/gr-settings-api_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-settings-api/gr-settings-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api.js b/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api.js
index 1de8283..c149ebe 100644
--- a/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api.js
+++ b/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api.js
@@ -38,7 +38,7 @@
    */
   GrStyleObject.prototype.getClassName = function(element) {
     let rootNode = Polymer.Settings.useShadow
-        ? element.getRootNode() : document.body;
+      ? element.getRootNode() : document.body;
     if (rootNode === document) {
       rootNode = document.head;
     }
@@ -62,7 +62,6 @@
     element.classList.add(this.getClassName(element));
   };
 
-
   function GrStylesApi() {
   }
 
@@ -75,6 +74,5 @@
     return new GrStyleObject(ruleStr);
   };
 
-
   window.GrStylesApi = GrStylesApi;
 })(window);
diff --git a/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api_test.html b/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api_test.html
index 46bda6d..7d14e21 100644
--- a/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-styles-api/gr-styles-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-admin-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -105,7 +105,6 @@
       return [element1, element2, element3];
     }
 
-
     test('getClassName  - body level elements', () => {
       const bodyLevelElements = createNestedElements(document.body);
 
@@ -161,7 +160,6 @@
       assertDisplayPropertyValues(elements, ['inline', 'none', 'inline']);
     }
 
-
     function assertAllElementsHaveDefaultStyle(elements) {
       for (const element of elements) {
         assert.equal(getComputedStyle(element).getPropertyValue('display'),
diff --git a/polygerrit-ui/app/elements/plugins/gr-theme-api/gr-theme-api_test.html b/polygerrit-ui/app/elements/plugins/gr-theme-api/gr-theme-api_test.html
index 6332b91..9401a15 100644
--- a/polygerrit-ui/app/elements/plugins/gr-theme-api/gr-theme-api_test.html
+++ b/polygerrit-ui/app/elements/plugins/gr-theme-api/gr-theme-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-theme-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.html b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.html
index 662c6f1..e685030 100644
--- a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.html
+++ b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.html
@@ -40,7 +40,9 @@
         display: none;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="gr-form-styles">
       <section>
         <span class="title"></span>
@@ -82,7 +84,6 @@
             hidden$="[[!usernameMutable]]"
             class="value">
           <iron-input
-              disabled="[[_saving]]"
               on-keydown="_handleKeydown"
               bind-value="{{_username}}">
             <input
@@ -103,7 +104,6 @@
             hidden$="[[!nameMutable]]"
             class="value">
           <iron-input
-              disabled="[[_saving]]"
               on-keydown="_handleKeydown"
               bind-value="{{_account.name}}">
             <input
@@ -119,7 +119,6 @@
         <span class="title">Status (e.g. "Vacation")</span>
         <span class="value">
           <iron-input
-              disabled="[[_saving]]"
               on-keydown="_handleKeydown"
               bind-value="{{_account.status}}">
             <input
diff --git a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.js b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.js
index b0c7661..e509b8b 100644
--- a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.js
+++ b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info.js
@@ -17,65 +17,71 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-account-info',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrAccountInfo extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-info'; }
     /**
      * Fired when account details are changed.
      *
      * @event account-detail-update
      */
 
-    properties: {
-      usernameMutable: {
-        type: Boolean,
-        notify: true,
-        computed: '_computeUsernameMutable(_serverConfig, _account.username)',
-      },
-      nameMutable: {
-        type: Boolean,
-        notify: true,
-        computed: '_computeNameMutable(_serverConfig)',
-      },
-      hasUnsavedChanges: {
-        type: Boolean,
-        notify: true,
-        computed: '_computeHasUnsavedChanges(_hasNameChange, ' +
+    static get properties() {
+      return {
+        usernameMutable: {
+          type: Boolean,
+          notify: true,
+          computed: '_computeUsernameMutable(_serverConfig, _account.username)',
+        },
+        nameMutable: {
+          type: Boolean,
+          notify: true,
+          computed: '_computeNameMutable(_serverConfig)',
+        },
+        hasUnsavedChanges: {
+          type: Boolean,
+          notify: true,
+          computed: '_computeHasUnsavedChanges(_hasNameChange, ' +
             '_hasUsernameChange, _hasStatusChange)',
-      },
+        },
 
-      _hasNameChange: Boolean,
-      _hasUsernameChange: Boolean,
-      _hasStatusChange: Boolean,
-      _loading: {
-        type: Boolean,
-        value: false,
-      },
-      _saving: {
-        type: Boolean,
-        value: false,
-      },
-      /** @type {?} */
-      _account: Object,
-      _serverConfig: Object,
-      _username: {
-        type: String,
-        observer: '_usernameChanged',
-      },
-      _avatarChangeUrl: {
-        type: String,
-        value: '',
-      },
-    },
+        _hasNameChange: Boolean,
+        _hasUsernameChange: Boolean,
+        _hasStatusChange: Boolean,
+        _loading: {
+          type: Boolean,
+          value: false,
+        },
+        _saving: {
+          type: Boolean,
+          value: false,
+        },
+        /** @type {?} */
+        _account: Object,
+        _serverConfig: Object,
+        _username: {
+          type: String,
+          observer: '_usernameChanged',
+        },
+        _avatarChangeUrl: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_nameChanged(_account.name)',
-      '_statusChanged(_account.status)',
-    ],
+    static get observers() {
+      return [
+        '_nameChanged(_account.name)',
+        '_statusChanged(_account.status)',
+      ];
+    }
 
     loadData() {
       const promises = [];
@@ -104,7 +110,7 @@
       return Promise.all(promises).then(() => {
         this._loading = false;
       });
-    },
+    }
 
     save() {
       if (!this.hasUnsavedChanges) {
@@ -123,29 +129,29 @@
             this._saving = false;
             this.fire('account-detail-update');
           });
-    },
+    }
 
     _maybeSetName() {
       return this._hasNameChange && this.nameMutable ?
-          this.$.restAPI.setAccountName(this._account.name) :
-          Promise.resolve();
-    },
+        this.$.restAPI.setAccountName(this._account.name) :
+        Promise.resolve();
+    }
 
     _maybeSetUsername() {
       return this._hasUsernameChange && this.usernameMutable ?
-          this.$.restAPI.setAccountUsername(this._username) :
-          Promise.resolve();
-    },
+        this.$.restAPI.setAccountUsername(this._username) :
+        Promise.resolve();
+    }
 
     _maybeSetStatus() {
       return this._hasStatusChange ?
-          this.$.restAPI.setAccountStatus(this._account.status) :
-          Promise.resolve();
-    },
+        this.$.restAPI.setAccountStatus(this._account.status) :
+        Promise.resolve();
+    }
 
     _computeHasUnsavedChanges(nameChanged, usernameChanged, statusChanged) {
       return nameChanged || usernameChanged || statusChanged;
-    },
+    }
 
     _computeUsernameMutable(config, username) {
       // Polymer 2: check for undefined
@@ -159,34 +165,34 @@
       // Username may not be changed once it is set.
       return config.auth.editable_account_fields.includes('USER_NAME') &&
           !username;
-    },
+    }
 
     _computeNameMutable(config) {
       return config.auth.editable_account_fields.includes('FULL_NAME');
-    },
+    }
 
     _statusChanged() {
       if (this._loading) { return; }
       this._hasStatusChange = true;
-    },
+    }
 
     _usernameChanged() {
       if (this._loading || !this._account) { return; }
       this._hasUsernameChange =
           (this._account.username || '') !== (this._username || '');
-    },
+    }
 
     _nameChanged() {
       if (this._loading) { return; }
       this._hasNameChange = true;
-    },
+    }
 
     _handleKeydown(e) {
       if (e.keyCode === 13) { // Enter
         e.stopPropagation();
         this.save();
       }
-    },
+    }
 
     _hideAvatarChangeUrl(avatarChangeUrl) {
       if (!avatarChangeUrl) {
@@ -194,6 +200,8 @@
       }
 
       return '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountInfo.is, GrAccountInfo);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info_test.html b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info_test.html
index de222a9..a9056b91 100644
--- a/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-account-info/gr-account-info_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-info</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -152,7 +152,7 @@
         usernameChangedSpy = sandbox.spy(element, '_usernameChanged');
         statusChangedSpy = sandbox.spy(element, '_statusChanged');
         element.set('_serverConfig',
-          {auth: {editable_account_fields: ['FULL_NAME', 'USER_NAME']}});
+            {auth: {editable_account_fields: ['FULL_NAME', 'USER_NAME']}});
 
         nameStub = sandbox.stub(element.$.restAPI, 'setAccountName',
             name => Promise.resolve());
@@ -280,7 +280,7 @@
       setup(() => {
         statusChangedSpy = sandbox.spy(element, '_statusChanged');
         element.set('_serverConfig',
-          {auth: {editable_account_fields: []}});
+            {auth: {editable_account_fields: []}});
 
         statusStub = sandbox.stub(element.$.restAPI, 'setAccountStatus',
             status => Promise.resolve());
diff --git a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.html b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.html
index 852161c..74d92d3 100644
--- a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.html
+++ b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.html
@@ -32,7 +32,9 @@
         width: auto;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="gr-form-styles">
       <table id="agreements">
         <thead>
diff --git a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.js b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.js
index 41595a98..13992f8 100644
--- a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.js
+++ b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list.js
@@ -17,33 +17,41 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-agreements-list',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    */
+  class GrAgreementsList extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-agreements-list'; }
 
-    properties: {
-      _agreements: Array,
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-    ],
+    static get properties() {
+      return {
+        _agreements: Array,
+      };
+    }
 
     attached() {
+      super.attached();
       this.loadData();
-    },
+    }
 
     loadData() {
       return this.$.restAPI.getAccountAgreements().then(agreements => {
         this._agreements = agreements;
       });
-    },
+    }
 
     getUrl() {
       return this.getBaseUrl() + '/settings/new-agreement';
-    },
+    }
 
     getUrlBase(item) {
       return this.getBaseUrl() + '/' + item;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAgreementsList.is, GrAgreementsList);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list_test.html b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list_test.html
index 14cf97c..cd5bc09 100644
--- a/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-agreements-list/gr-agreements-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.html b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.html
index 88a53ee..09a9dbc 100644
--- a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.html
@@ -24,7 +24,9 @@
 
 <dom-module id="gr-change-table-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       #changeCols {
         width: auto;
diff --git a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.js b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.js
index 85eed9c..d92c148 100644
--- a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor.js
@@ -17,23 +17,28 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-change-table-editor',
+  /**
+    * @appliesMixin Gerrit.ChangeTableMixin
+    */
+  class GrChangeTableEditor extends Polymer.mixinBehaviors( [
+    Gerrit.ChangeTableBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-change-table-editor'; }
 
-    properties: {
-      displayedColumns: {
-        type: Array,
-        notify: true,
-      },
-      showNumber: {
-        type: Boolean,
-        notify: true,
-      },
-    },
-
-    behaviors: [
-      Gerrit.ChangeTableBehavior,
-    ],
+    static get properties() {
+      return {
+        displayedColumns: {
+          type: Array,
+          notify: true,
+        },
+        showNumber: {
+          type: Boolean,
+          notify: true,
+        },
+      };
+    }
 
     /**
      * Get the list of enabled column names from whichever checkboxes are
@@ -45,7 +50,7 @@
           .querySelectorAll('.checkboxContainer input:not([name=number])'))
           .filter(checkbox => checkbox.checked)
           .map(checkbox => checkbox.name);
-    },
+    }
 
     /**
      * Handle a click on a checkbox container and relay the click to the checkbox it
@@ -55,7 +60,7 @@
       const checkbox = Polymer.dom(e.target).querySelector('input');
       if (!checkbox) { return; }
       checkbox.click();
-    },
+    }
 
     /**
      * Handle a click on the number checkbox and update the showNumber property
@@ -63,7 +68,7 @@
      */
     _handleNumberCheckboxClick(e) {
       this.showNumber = Polymer.dom(e).rootTarget.checked;
-    },
+    }
 
     /**
      * Handle a click on a displayed column checkboxes (excluding number) and
@@ -71,6 +76,8 @@
      */
     _handleTargetClick(e) {
       this.set('displayedColumns', this._getDisplayedColumns());
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeTableEditor.is, GrChangeTableEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor_test.html b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor_test.html
index 29a7081..ec37c03 100644
--- a/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-change-table-editor/gr-change-table-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.html b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.html
index c29153e..fb5d64f 100644
--- a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.html
+++ b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.html
@@ -66,7 +66,9 @@
         max-width: 50em;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <main>
       <h1>New Contributor Agreement</h1>
       <h3>Select an agreement type:</h3>
diff --git a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.js b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.js
index 9abd08d..863577c 100644
--- a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.js
+++ b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view.js
@@ -17,33 +17,40 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-cla-view',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrClaView extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-cla-view'; }
 
-    properties: {
-      _groups: Object,
-      /** @type {?} */
-      _serverConfig: Object,
-      _agreementsText: String,
-      _agreementName: String,
-      _signedAgreements: Array,
-      _showAgreements: {
-        type: Boolean,
-        value: false,
-      },
-      _agreementsUrl: String,
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        _groups: Object,
+        /** @type {?} */
+        _serverConfig: Object,
+        _agreementsText: String,
+        _agreementName: String,
+        _signedAgreements: Array,
+        _showAgreements: {
+          type: Boolean,
+          value: false,
+        },
+        _agreementsUrl: String,
+      };
+    }
 
     attached() {
+      super.attached();
       this.loadData();
 
       this.fire('title-change', {title: 'New Contributor Agreement'});
-    },
+    }
 
     loadData() {
       const promises = [];
@@ -62,7 +69,7 @@
       }));
 
       return Promise.all(promises);
-    },
+    }
 
     _getAgreementsUrl(configUrl) {
       let url;
@@ -76,14 +83,14 @@
       }
 
       return url;
-    },
+    }
 
     _handleShowAgreement(e) {
       this._agreementName = e.target.getAttribute('data-name');
       this._agreementsUrl =
           this._getAgreementsUrl(e.target.getAttribute('data-url'));
       this._showAgreements = true;
-    },
+    }
 
     _handleSaveAgreements(e) {
       this._createToast('Agreement saving...');
@@ -99,16 +106,16 @@
         this._agreementsText = '';
         this._showAgreements = false;
       });
-    },
+    }
 
     _createToast(message) {
       this.dispatchEvent(new CustomEvent(
           'show-alert', {detail: {message}, bubbles: true, composed: true}));
-    },
+    }
 
     _computeShowAgreementsClass(agreements) {
       return agreements ? 'show' : '';
-    },
+    }
 
     _disableAgreements(item, groups, signedAgreements) {
       if (!groups) return false;
@@ -120,16 +127,16 @@
         }
       }
       return false;
-    },
+    }
 
     _hideAgreements(item, groups, signedAgreements) {
       return this._disableAgreements(item, groups, signedAgreements) ?
-          '' : 'hide';
-    },
+        '' : 'hide';
+    }
 
     _disableAgreementsText(text) {
       return text.toLowerCase() === 'i agree' ? false : true;
-    },
+    }
 
     // This checks for auto_verify_group,
     // if specified it returns 'hideAgreementsTextBox' which
@@ -150,6 +157,8 @@
           }
         }
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrClaView.is, GrClaView);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view_test.html b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view_test.html
index f1b65d9..13c4de4 100644
--- a/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-cla-view/gr-cla-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-cla-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.html b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.html
index 53a30c3..80440c7 100644
--- a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.html
+++ b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.html
@@ -24,8 +24,12 @@
 
 <dom-module id="gr-edit-preferences">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-form-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div id="editPreferences" class="gr-form-styles">
       <section>
         <span class="title">Tab width</span>
diff --git a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.js b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.js
index 86350f9..36e53b0 100644
--- a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.js
+++ b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences.js
@@ -17,66 +17,72 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-edit-preferences',
+  class GrEditPreferences extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-edit-preferences'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
 
-      /** @type {?} */
-      editPrefs: Object,
-    },
+        /** @type {?} */
+        editPrefs: Object,
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getEditPreferences().then(prefs => {
         this.editPrefs = prefs;
       });
-    },
+    }
 
     _handleEditPrefsChanged() {
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleEditSyntaxHighlightingChanged() {
       this.set('editPrefs.syntax_highlighting',
           this.$.editSyntaxHighlighting.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     _handleEditShowTabsChanged() {
       this.set('editPrefs.show_tabs', this.$.editShowTabs.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     _handleMatchBracketsChanged() {
       this.set('editPrefs.match_brackets', this.$.showMatchBrackets.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     _handleEditLineWrappingChanged() {
       this.set('editPrefs.line_wrapping', this.$.editShowLineWrapping.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     _handleIndentWithTabsChanged() {
       this.set('editPrefs.indent_with_tabs', this.$.showIndentWithTabs.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     _handleAutoCloseBracketsChanged() {
       this.set('editPrefs.auto_close_brackets',
           this.$.showAutoCloseBrackets.checked);
       this._handleEditPrefsChanged();
-    },
+    }
 
     save() {
       return this.$.restAPI.saveEditPreferences(this.editPrefs).then(res => {
         this.hasUnsavedChanges = false;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditPreferences.is, GrEditPreferences);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences_test.html b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences_test.html
index c1c5c52..8b0bf86 100644
--- a/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-edit-preferences/gr-edit-preferences_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-edit-preferences</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.html b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.html
index caaf18b..041b2a7 100644
--- a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.html
@@ -23,7 +23,9 @@
 
 <dom-module id="gr-email-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       th {
         color: var(--deemphasized-text-color);
diff --git a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.js b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.js
index 8490b26..8ec1067 100644
--- a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor.js
@@ -17,33 +17,37 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-email-editor',
+  class GrEmailEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-email-editor'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
 
-      _emails: Array,
-      _emailsToRemove: {
-        type: Array,
-        value() { return []; },
-      },
-      /** @type {?string} */
-      _newPreferred: {
-        type: String,
-        value: null,
-      },
-    },
+        _emails: Array,
+        _emailsToRemove: {
+          type: Array,
+          value() { return []; },
+        },
+        /** @type {?string} */
+        _newPreferred: {
+          type: String,
+          value: null,
+        },
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getAccountEmails().then(emails => {
         this._emails = emails;
       });
-    },
+    }
 
     save() {
       const promises = [];
@@ -62,7 +66,7 @@
         this._newPreferred = null;
         this.hasUnsavedChanges = false;
       });
-    },
+    }
 
     _handleDeleteButton(e) {
       const index = parseInt(Polymer.dom(e).localTarget
@@ -71,13 +75,13 @@
       this.push('_emailsToRemove', email);
       this.splice('_emails', index, 1);
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handlePreferredControlClick(e) {
       if (e.target.classList.contains('preferredControl')) {
         e.target.firstElementChild.click();
       }
-    },
+    }
 
     _handlePreferredChange(e) {
       const preferred = e.target.value;
@@ -90,6 +94,8 @@
           this.set(['_emails', i, 'preferred'], false);
         }
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEmailEditor.is, GrEmailEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor_test.html b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor_test.html
index 8d3f2d2..e55ac97 100644
--- a/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-email-editor/gr-email-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-email-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.html b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.html
index cf73d99..7b8a191 100644
--- a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.html
@@ -26,7 +26,9 @@
 
 <dom-module id="gr-gpg-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       .keyHeader {
         width: 9em;
diff --git a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.js b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.js
index 78025d1..14d7a4c 100644
--- a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor.js
@@ -17,27 +17,31 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-gpg-editor',
+  class GrGpgEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-gpg-editor'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        value: false,
-        notify: true,
-      },
-      _keys: Array,
-      /** @type {?} */
-      _keyToView: Object,
-      _newKey: {
-        type: String,
-        value: '',
-      },
-      _keysToRemove: {
-        type: Array,
-        value() { return []; },
-      },
-    },
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          value: false,
+          notify: true,
+        },
+        _keys: Array,
+        /** @type {?} */
+        _keyToView: Object,
+        _newKey: {
+          type: String,
+          value: '',
+        },
+        _keysToRemove: {
+          type: Array,
+          value() { return []; },
+        },
+      };
+    }
 
     loadData() {
       this._keys = [];
@@ -46,13 +50,13 @@
           return;
         }
         this._keys = Object.keys(keys)
-         .map(key => {
-           const gpgKey = keys[key];
-           gpgKey.id = key;
-           return gpgKey;
-         });
+            .map(key => {
+              const gpgKey = keys[key];
+              gpgKey.id = key;
+              return gpgKey;
+            });
       });
-    },
+    }
 
     save() {
       const promises = this._keysToRemove.map(key => {
@@ -63,18 +67,18 @@
         this._keysToRemove = [];
         this.hasUnsavedChanges = false;
       });
-    },
+    }
 
     _showKey(e) {
       const el = Polymer.dom(e).localTarget;
       const index = parseInt(el.getAttribute('data-index'), 10);
       this._keyToView = this._keys[index];
       this.$.viewKeyOverlay.open();
-    },
+    }
 
     _closeOverlay() {
       this.$.viewKeyOverlay.close();
-    },
+    }
 
     _handleDeleteKey(e) {
       const el = Polymer.dom(e).localTarget;
@@ -82,7 +86,7 @@
       this.push('_keysToRemove', this._keys[index]);
       this.splice('_keys', index, 1);
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleAddKey() {
       this.$.addButton.disabled = true;
@@ -96,10 +100,12 @@
             this.$.addButton.disabled = false;
             this.$.newKey.disabled = false;
           });
-    },
+    }
 
     _computeAddButtonDisabled(newKey) {
       return !newKey.length;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrGpgEditor.is, GrGpgEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor_test.html b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor_test.html
index 9cfbde5f..575285b 100644
--- a/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-gpg-editor/gr-gpg-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-gpg-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.html b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.html
index ca500c8..e51294d 100644
--- a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.html
+++ b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.html
@@ -23,7 +23,9 @@
 
 <dom-module id="gr-group-list">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
         #groups .nameColumn {
           min-width: 11em;
diff --git a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.js b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.js
index d62a241..87fb852 100644
--- a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.js
+++ b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list.js
@@ -17,12 +17,16 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-group-list',
+  class GrGroupList extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-group-list'; }
 
-    properties: {
-      _groups: Array,
-    },
+    static get properties() {
+      return {
+        _groups: Array,
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getAccountGroups().then(groups => {
@@ -30,11 +34,11 @@
           return a.name.localeCompare(b.name);
         });
       });
-    },
+    }
 
     _computeVisibleToAll(group) {
       return group.options.visible_to_all ? 'Yes' : 'No';
-    },
+    }
 
     _computeGroupPath(group) {
       if (!group || !group.id) { return; }
@@ -42,6 +46,8 @@
       // Group ID is already encoded from the API
       // Decode it here to match with our router encoding behavior
       return Gerrit.Nav.getUrlForGroup(decodeURIComponent(group.id));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrGroupList.is, GrGroupList);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list_test.html b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list_test.html
index 3c3ece3..d8bf888 100644
--- a/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-group-list/gr-group-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.html b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.html
index 0cb9695..22ba457 100644
--- a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.html
+++ b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.html
@@ -56,7 +56,9 @@
         right: 2em;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="gr-form-styles">
       <div hidden$="[[_passwordUrl]]">
         <section>
diff --git a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.js b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.js
index 003e471..5c0a059 100644
--- a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.js
+++ b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password.js
@@ -17,18 +17,23 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-http-password',
+  class GrHttpPassword extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-http-password'; }
 
-    properties: {
-      _username: String,
-      _generatedPassword: String,
-      _passwordUrl: String,
-    },
+    static get properties() {
+      return {
+        _username: String,
+        _generatedPassword: String,
+        _passwordUrl: String,
+      };
+    }
 
     attached() {
+      super.attached();
       this.loadData();
-    },
+    }
 
     loadData() {
       const promises = [];
@@ -42,7 +47,7 @@
       }));
 
       return Promise.all(promises);
-    },
+    }
 
     _handleGenerateTap() {
       this._generatedPassword = 'Generating...';
@@ -50,14 +55,16 @@
       this.$.restAPI.generateAccountHttpPassword().then(newPassword => {
         this._generatedPassword = newPassword;
       });
-    },
+    }
 
     _closeOverlay() {
       this.$.generatedPasswordOverlay.close();
-    },
+    }
 
     _generatedPasswordOverlayClosed() {
       this._generatedPassword = '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrHttpPassword.is, GrHttpPassword);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password_test.html b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password_test.html
index 8924058..89da766 100644
--- a/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-http-password/gr-http-password_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.html b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.html
index ee855cc..53d74f2 100644
--- a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.html
+++ b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.html
@@ -26,7 +26,9 @@
 
 <dom-module id="gr-identities">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       tr th.emailAddressHeader,
       tr th.identityHeader {
diff --git a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.js b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.js
index c927f1e..94c9e5a 100644
--- a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.js
+++ b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities.js
@@ -22,61 +22,66 @@
     'OAUTH',
   ];
 
-  Polymer({
-    is: 'gr-identities',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    */
+  class GrIdentities extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-identities'; }
 
-    properties: {
-      _identities: Object,
-      _idName: String,
-      serverConfig: Object,
-      _showLinkAnotherIdentity: {
-        type: Boolean,
-        computed: '_computeShowLinkAnotherIdentity(serverConfig)',
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-    ],
+    static get properties() {
+      return {
+        _identities: Object,
+        _idName: String,
+        serverConfig: Object,
+        _showLinkAnotherIdentity: {
+          type: Boolean,
+          computed: '_computeShowLinkAnotherIdentity(serverConfig)',
+        },
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getExternalIds().then(id => {
         this._identities = id;
       });
-    },
+    }
 
     _computeIdentity(id) {
       return id && id.startsWith('mailto:') ? '' : id;
-    },
+    }
 
     _computeHideDeleteClass(canDelete) {
       return canDelete ? 'show' : '';
-    },
+    }
 
     _handleDeleteItemConfirm() {
       this.$.overlay.close();
       return this.$.restAPI.deleteAccountIdentity([this._idName])
           .then(() => { this.loadData(); });
-    },
+    }
 
     _handleConfirmDialogCancel() {
       this.$.overlay.close();
-    },
+    }
 
     _handleDeleteItem(e) {
       const name = e.model.get('item.identity');
       if (!name) { return; }
       this._idName = name;
       this.$.overlay.open();
-    },
+    }
 
     _computeIsTrusted(item) {
       return item ? '' : 'Untrusted';
-    },
+    }
 
     filterIdentities(item) {
       return !item.identity.startsWith('username:');
-    },
+    }
 
     _computeShowLinkAnotherIdentity(config) {
       if (config && config.auth &&
@@ -86,7 +91,7 @@
       }
 
       return false;
-    },
+    }
 
     _computeLinkAnotherIdentity() {
       const baseUrl = this.getBaseUrl() || '';
@@ -95,6 +100,8 @@
         pathname = '/' + pathname.substring(baseUrl.length);
       }
       return baseUrl + '/login/' + encodeURIComponent(pathname) + '?link';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrIdentities.is, GrIdentities);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities_test.html b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities_test.html
index 1277424..e2f8cad 100644
--- a/polygerrit-ui/app/elements/settings/gr-identities/gr-identities_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-identities/gr-identities_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-identities</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.html b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.html
index 1485628..46fc165 100644
--- a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.html
@@ -44,7 +44,9 @@
         min-width: 23em;
       }
     </style>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="gr-form-styles">
       <table>
         <thead>
diff --git a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.js b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.js
index 4f3c0c7..5b6c978 100644
--- a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor.js
@@ -17,14 +17,18 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-menu-editor',
+  class GrMenuEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-menu-editor'; }
 
-    properties: {
-      menuItems: Array,
-      _newName: String,
-      _newUrl: String,
-    },
+    static get properties() {
+      return {
+        menuItems: Array,
+        _newName: String,
+        _newUrl: String,
+      };
+    }
 
     _handleMoveUpButton(e) {
       const index = Number(Polymer.dom(e).localTarget.dataset.index);
@@ -32,7 +36,7 @@
       const row = this.menuItems[index];
       const prev = this.menuItems[index - 1];
       this.splice('menuItems', index - 1, 2, row, prev);
-    },
+    }
 
     _handleMoveDownButton(e) {
       const index = Number(Polymer.dom(e).localTarget.dataset.index);
@@ -40,12 +44,12 @@
       const row = this.menuItems[index];
       const next = this.menuItems[index + 1];
       this.splice('menuItems', index, 2, next, row);
-    },
+    }
 
     _handleDeleteButton(e) {
       const index = Number(Polymer.dom(e).localTarget.dataset.index);
       this.splice('menuItems', index, 1);
-    },
+    }
 
     _handleAddButton() {
       if (this._computeAddDisabled(this._newName, this._newUrl)) { return; }
@@ -58,17 +62,19 @@
 
       this._newName = '';
       this._newUrl = '';
-    },
+    }
 
     _computeAddDisabled(newName, newUrl) {
       return !newName.length || !newUrl.length;
-    },
+    }
 
     _handleInputKeydown(e) {
       if (e.keyCode === 13) {
         e.stopPropagation();
         this._handleAddButton();
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrMenuEditor.is, GrMenuEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor_test.html b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor_test.html
index 134e018..380e00a 100644
--- a/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-menu-editor/gr-menu-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.html b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.html
index f366d2a..c289a49 100644
--- a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.html
+++ b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.html
@@ -26,7 +26,9 @@
 
 <dom-module id="gr-registration-dialog">
   <template>
-    <style include="gr-form-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       :host {
         display: block;
@@ -84,8 +86,7 @@
         <section>
           <div class="title">Full Name</div>
           <iron-input
-              bind-value="{{_account.name}}"
-              disabled="[[_saving]]">
+              bind-value="{{_account.name}}">
             <input
                 is="iron-input"
                 id="name"
@@ -96,8 +97,7 @@
         <section class$="[[_computeUsernameClass(_usernameMutable)]]">
           <div class="title">Username</div>
           <iron-input
-              bind-value="{{_account.username}}"
-              disabled="[[_saving]]">
+              bind-value="{{_account.username}}">
             <input
                 is="iron-input"
                 id="username"
diff --git a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.js b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.js
index 0633416..af23f5b 100644
--- a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.js
+++ b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog.js
@@ -17,9 +17,15 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-registration-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrRegistrationDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-registration-dialog'; }
     /**
      * Fired when account details are changed.
      *
@@ -32,40 +38,39 @@
      * @event close
      */
 
-    properties: {
-      settingsUrl: String,
-      /** @type {?} */
-      _account: {
-        type: Object,
-        value: () => {
+    static get properties() {
+      return {
+        settingsUrl: String,
+        /** @type {?} */
+        _account: {
+          type: Object,
+          value: () => {
           // Prepopulate possibly undefined fields with values to trigger
           // computed bindings.
-          return {email: null, name: null, username: null};
+            return {email: null, name: null, username: null};
+          },
         },
-      },
-      _usernameMutable: {
-        type: Boolean,
-        computed: '_computeUsernameMutable(_serverConfig, _account.username)',
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-        observer: '_loadingChanged',
-      },
-      _saving: {
-        type: Boolean,
-        value: false,
-      },
-      _serverConfig: Object,
-    },
+        _usernameMutable: {
+          type: Boolean,
+          computed: '_computeUsernameMutable(_serverConfig, _account.username)',
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+          observer: '_loadingChanged',
+        },
+        _saving: {
+          type: Boolean,
+          value: false,
+        },
+        _serverConfig: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    hostAttributes: {
-      role: 'dialog',
-    },
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'dialog');
+    }
 
     loadData() {
       this._loading = true;
@@ -84,7 +89,7 @@
       return Promise.all([loadAccount, loadConfig]).then(() => {
         this._loading = false;
       });
-    },
+    }
 
     _save() {
       this._saving = true;
@@ -101,26 +106,26 @@
         this._saving = false;
         this.fire('account-detail-update');
       });
-    },
+    }
 
     _handleSave(e) {
       e.preventDefault();
       this._save().then(this.close.bind(this));
-    },
+    }
 
     _handleClose(e) {
       e.preventDefault();
       this.close();
-    },
+    }
 
     close() {
       this._saving = true; // disable buttons indefinitely
       this.fire('close');
-    },
+    }
 
     _computeSaveDisabled(name, email, saving) {
       return !name || !email || saving;
-    },
+    }
 
     _computeUsernameMutable(config, username) {
       // Polymer 2: check for undefined
@@ -133,14 +138,16 @@
 
       return config.auth.editable_account_fields.includes('USER_NAME') &&
           !username;
-    },
+    }
 
     _computeUsernameClass(usernameMutable) {
       return usernameMutable ? '' : 'hide';
-    },
+    }
 
     _loadingChanged() {
       this.classList.toggle('loading', this._loading);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRegistrationDialog.is, GrRegistrationDialog);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
index d1b5c80..a987a26 100644
--- a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-registration-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-item.js b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-item.js
index dae3b68..9702280 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-item.js
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-item.js
@@ -17,12 +17,18 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-settings-item',
+  class GrSettingsItem extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-settings-item'; }
 
-    properties: {
-      anchor: String,
-      title: String,
-    },
-  });
+    static get properties() {
+      return {
+        anchor: String,
+        title: String,
+      };
+    }
+  }
+
+  customElements.define(GrSettingsItem.is, GrSettingsItem);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.html b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.html
index 846f776..c356e80 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.html
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.html
@@ -20,8 +20,12 @@
 
 <dom-module id="gr-settings-menu-item">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-page-nav-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-page-nav-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="navStyles">
       <li><a href$="[[href]]">[[title]]</a></li>
     </div>
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.js b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.js
index 5db0031..e08e3d8 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.js
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-menu-item.js
@@ -17,12 +17,18 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-settings-menu-item',
+  class GrSettingsMenuItem extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-settings-menu-item'; }
 
-    properties: {
-      href: String,
-      title: String,
-    },
-  });
+    static get properties() {
+      return {
+        href: String,
+        title: String,
+      };
+    }
+  }
+
+  customElements.define(GrSettingsMenuItem.is, GrSettingsMenuItem);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.html b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.html
index 74971cf..e71aef5 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.html
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.html
@@ -74,9 +74,15 @@
         margin-right: var(--spacing-l);
       }
     </style>
-    <style include="gr-form-styles"></style>
-    <style include="gr-menu-page-styles"></style>
-    <style include="gr-page-nav-styles"></style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-menu-page-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-page-nav-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div class="loading" hidden$="[[!_loading]]">Loading...</div>
     <div hidden$="[[_loading]]" hidden>
       <gr-page-nav class="navStyles">
@@ -131,7 +137,6 @@
         <fieldset id="profile">
           <gr-account-info
               id="accountInfo"
-              mutable="{{_accountNameMutable}}"
               has-unsaved-changes="{{_accountInfoChanged}}"></gr-account-info>
           <gr-button
               on-click="_handleSaveAccountInfo"
@@ -373,7 +378,6 @@
                   class="newEmailInput"
                   bind-value="{{_newEmail}}"
                   type="text"
-                  disabled="[[_addingEmail]]"
                   on-keydown="_handleNewEmailKeydown"
                   placeholder="email@example.com">
                 <input
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.js b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.js
index 714faab..39ca220 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.js
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.js
@@ -45,9 +45,19 @@
     'HTTP_LDAP',
   ];
 
-  Polymer({
-    is: 'gr-settings-view',
-
+  /**
+    * @appliesMixin Gerrit.DocsUrlMixin
+    * @appliesMixin Gerrit.ChangeTableMixin
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrSettingsView extends Polymer.mixinBehaviors( [
+    Gerrit.DocsUrlBehavior,
+    Gerrit.ChangeTableBehavior,
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-settings-view'; }
     /**
      * Fired when the title of the page should change.
      *
@@ -60,104 +70,102 @@
      * @event show-alert
      */
 
-    properties: {
-      prefs: {
-        type: Object,
-        value() { return {}; },
-      },
-      params: {
-        type: Object,
-        value() { return {}; },
-      },
-      _accountNameMutable: Boolean,
-      _accountInfoChanged: Boolean,
-      _changeTableColumnsNotDisplayed: Array,
-      /** @type {?} */
-      _localPrefs: {
-        type: Object,
-        value() { return {}; },
-      },
-      _localChangeTableColumns: {
-        type: Array,
-        value() { return []; },
-      },
-      _localMenu: {
-        type: Array,
-        value() { return []; },
-      },
-      _loading: {
-        type: Boolean,
-        value: true,
-      },
-      _changeTableChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _prefsChanged: {
-        type: Boolean,
-        value: false,
-      },
-      /** @type {?} */
-      _diffPrefsChanged: Boolean,
-      /** @type {?} */
-      _editPrefsChanged: Boolean,
-      _menuChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _watchedProjectsChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _keysChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _gpgKeysChanged: {
-        type: Boolean,
-        value: false,
-      },
-      _newEmail: String,
-      _addingEmail: {
-        type: Boolean,
-        value: false,
-      },
-      _lastSentVerificationEmail: {
-        type: String,
-        value: null,
-      },
-      /** @type {?} */
-      _serverConfig: Object,
-      /** @type {?string} */
-      _docsBaseUrl: String,
-      _emailsChanged: Boolean,
+    static get properties() {
+      return {
+        prefs: {
+          type: Object,
+          value() { return {}; },
+        },
+        params: {
+          type: Object,
+          value() { return {}; },
+        },
+        _accountInfoChanged: Boolean,
+        _changeTableColumnsNotDisplayed: Array,
+        /** @type {?} */
+        _localPrefs: {
+          type: Object,
+          value() { return {}; },
+        },
+        _localChangeTableColumns: {
+          type: Array,
+          value() { return []; },
+        },
+        _localMenu: {
+          type: Array,
+          value() { return []; },
+        },
+        _loading: {
+          type: Boolean,
+          value: true,
+        },
+        _changeTableChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _prefsChanged: {
+          type: Boolean,
+          value: false,
+        },
+        /** @type {?} */
+        _diffPrefsChanged: Boolean,
+        /** @type {?} */
+        _editPrefsChanged: Boolean,
+        _menuChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _watchedProjectsChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _keysChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _gpgKeysChanged: {
+          type: Boolean,
+          value: false,
+        },
+        _newEmail: String,
+        _addingEmail: {
+          type: Boolean,
+          value: false,
+        },
+        _lastSentVerificationEmail: {
+          type: String,
+          value: null,
+        },
+        /** @type {?} */
+        _serverConfig: Object,
+        /** @type {?string} */
+        _docsBaseUrl: String,
+        _emailsChanged: Boolean,
 
-      /**
+        /**
        * For testing purposes.
        */
-      _loadingPromise: Object,
+        _loadingPromise: Object,
 
-      _showNumber: Boolean,
+        _showNumber: Boolean,
 
-      _isDark: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _isDark: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.DocsUrlBehavior,
-      Gerrit.ChangeTableBehavior,
-      Gerrit.FireBehavior,
-    ],
-
-    observers: [
-      '_handlePrefsChanged(_localPrefs.*)',
-      '_handleMenuChanged(_localMenu.splices)',
-      '_handleChangeTableChanged(_localChangeTableColumns, _showNumber)',
-    ],
+    static get observers() {
+      return [
+        '_handlePrefsChanged(_localPrefs.*)',
+        '_handleMenuChanged(_localMenu.splices)',
+        '_handleChangeTableChanged(_localChangeTableColumns, _showNumber)',
+      ];
+    }
 
     attached() {
+      super.attached();
       // Polymer 2: anchor tag won't work on shadow DOM
       // we need to manually calling scrollIntoView when hash changed
       this.listen(window, 'location-change', '_handleLocationChange');
@@ -221,11 +229,12 @@
         // Handle anchor tag for initial load
         this._handleLocationChange();
       });
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'location-change', '_handleLocationChange');
-    },
+    }
 
     _handleLocationChange() {
       // Handle anchor tag after dom attached
@@ -237,25 +246,25 @@
           elem.scrollIntoView();
         }
       }
-    },
+    }
 
     reloadAccountDetail() {
       Promise.all([
         this.$.accountInfo.loadData(),
         this.$.emailEditor.loadData(),
       ]);
-    },
+    }
 
     _isLoading() {
       return this._loading || this._loading === undefined;
-    },
+    }
 
     _copyPrefs(to, from) {
       for (let i = 0; i < PREFS_SECTION_FIELDS.length; i++) {
         this.set([to, PREFS_SECTION_FIELDS[i]],
             this[from][PREFS_SECTION_FIELDS[i]]);
       }
-    },
+    }
 
     _cloneMenu(prefs) {
       const menu = [];
@@ -267,7 +276,7 @@
         });
       }
       this._localMenu = menu;
-    },
+    }
 
     _cloneChangeTableColumns() {
       let columns = this.getVisibleColumns(this.prefs.change_table);
@@ -280,56 +289,56 @@
             this.prefs.change_table);
       }
       this._localChangeTableColumns = columns;
-    },
+    }
 
     _formatChangeTableColumns(changeTableArray) {
       return changeTableArray.map(item => {
         return {column: item};
       });
-    },
+    }
 
     _handleChangeTableChanged() {
       if (this._isLoading()) { return; }
       this._changeTableChanged = true;
-    },
+    }
 
     _handlePrefsChanged(prefs) {
       if (this._isLoading()) { return; }
       this._prefsChanged = true;
-    },
+    }
 
     _handleRelativeDateInChangeTable() {
       this.set('_localPrefs.relative_date_in_change_table',
           this.$.relativeDateInChangeTable.checked);
-    },
+    }
 
     _handleShowSizeBarsInFileListChanged() {
       this.set('_localPrefs.size_bar_in_change_table',
           this.$.showSizeBarsInFileList.checked);
-    },
+    }
 
     _handlePublishCommentsOnPushChanged() {
       this.set('_localPrefs.publish_comments_on_push',
           this.$.publishCommentsOnPush.checked);
-    },
+    }
 
     _handleWorkInProgressByDefault() {
       this.set('_localPrefs.work_in_progress_by_default',
           this.$.workInProgressByDefault.checked);
-    },
+    }
 
     _handleInsertSignedOff() {
       this.set('_localPrefs.signed_off_by', this.$.insertSignedOff.checked);
-    },
+    }
 
     _handleMenuChanged() {
       if (this._isLoading()) { return; }
       this._menuChanged = true;
-    },
+    }
 
     _handleSaveAccountInfo() {
       this.$.accountInfo.save();
-    },
+    }
 
     _handleSavePreferences() {
       this._copyPrefs('prefs', '_localPrefs');
@@ -337,7 +346,7 @@
       return this.$.restAPI.savePreferences(this.prefs).then(() => {
         this._prefsChanged = false;
       });
-    },
+    }
 
     _handleSaveChangeTable() {
       this.set('prefs.change_table', this._localChangeTableColumns);
@@ -346,15 +355,15 @@
       return this.$.restAPI.savePreferences(this.prefs).then(() => {
         this._changeTableChanged = false;
       });
-    },
+    }
 
     _handleSaveDiffPreferences() {
       this.$.diffPrefs.save();
-    },
+    }
 
     _handleSaveEditPreferences() {
       this.$.editPrefs.save();
-    },
+    }
 
     _handleSaveMenu() {
       this.set('prefs.my', this._localMenu);
@@ -362,7 +371,7 @@
       return this.$.restAPI.savePreferences(this.prefs).then(() => {
         this._menuChanged = false;
       });
-    },
+    }
 
     _handleResetMenuButton() {
       return this.$.restAPI.getDefaultPreferences().then(data => {
@@ -370,34 +379,34 @@
           this._cloneMenu(data.my);
         }
       });
-    },
+    }
 
     _handleSaveWatchedProjects() {
       this.$.watchedProjectsEditor.save();
-    },
+    }
 
     _computeHeaderClass(changed) {
       return changed ? 'edited' : '';
-    },
+    }
 
     _handleSaveEmails() {
       this.$.emailEditor.save();
-    },
+    }
 
     _handleNewEmailKeydown(e) {
       if (e.keyCode === 13) { // Enter
         e.stopPropagation();
         this._handleAddEmailButton();
       }
-    },
+    }
 
     _isNewEmailValid(newEmail) {
       return newEmail && newEmail.includes('@');
-    },
+    }
 
     _computeAddEmailButtonEnabled(newEmail, addingEmail) {
       return this._isNewEmailValid(newEmail) && !addingEmail;
-    },
+    }
 
     _handleAddEmailButton() {
       if (!this._isNewEmailValid(this._newEmail)) { return; }
@@ -412,7 +421,7 @@
         this._lastSentVerificationEmail = this._newEmail;
         this._newEmail = '';
       });
-    },
+    }
 
     _getFilterDocsLink(docsBaseUrl) {
       let base = docsBaseUrl;
@@ -424,7 +433,7 @@
       base = base.replace(TRAILING_SLASH_PATTERN, '');
 
       return base + GERRIT_DOCS_FILTER_PATH;
-    },
+    }
 
     _handleToggleDark() {
       if (this._isDark) {
@@ -440,7 +449,7 @@
       this.async(() => {
         window.location.reload();
       }, 1);
-    },
+    }
 
     _showHttpAuth(config) {
       if (config && config.auth &&
@@ -450,6 +459,8 @@
       }
 
       return false;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSettingsView.is, GrSettingsView);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view_test.html b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view_test.html
index 6dcf124..24ee69b 100644
--- a/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.html b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.html
index 2a27194..dd02ccd 100644
--- a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.html
@@ -26,7 +26,9 @@
 
 <dom-module id="gr-ssh-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       .statusHeader {
         width: 4em;
diff --git a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.js b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.js
index 874173a..6e17817 100644
--- a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor.js
@@ -17,33 +17,37 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-ssh-editor',
+  class GrSshEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-ssh-editor'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        value: false,
-        notify: true,
-      },
-      _keys: Array,
-      /** @type {?} */
-      _keyToView: Object,
-      _newKey: {
-        type: String,
-        value: '',
-      },
-      _keysToRemove: {
-        type: Array,
-        value() { return []; },
-      },
-    },
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          value: false,
+          notify: true,
+        },
+        _keys: Array,
+        /** @type {?} */
+        _keyToView: Object,
+        _newKey: {
+          type: String,
+          value: '',
+        },
+        _keysToRemove: {
+          type: Array,
+          value() { return []; },
+        },
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getAccountSSHKeys().then(keys => {
         this._keys = keys;
       });
-    },
+    }
 
     save() {
       const promises = this._keysToRemove.map(key => {
@@ -54,22 +58,22 @@
         this._keysToRemove = [];
         this.hasUnsavedChanges = false;
       });
-    },
+    }
 
     _getStatusLabel(isValid) {
       return isValid ? 'Valid' : 'Invalid';
-    },
+    }
 
     _showKey(e) {
       const el = Polymer.dom(e).localTarget;
       const index = parseInt(el.getAttribute('data-index'), 10);
       this._keyToView = this._keys[index];
       this.$.viewKeyOverlay.open();
-    },
+    }
 
     _closeOverlay() {
       this.$.viewKeyOverlay.close();
-    },
+    }
 
     _handleDeleteKey(e) {
       const el = Polymer.dom(e).localTarget;
@@ -77,7 +81,7 @@
       this.push('_keysToRemove', this._keys[index]);
       this.splice('_keys', index, 1);
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleAddKey() {
       this.$.addButton.disabled = true;
@@ -91,10 +95,12 @@
             this.$.addButton.disabled = false;
             this.$.newKey.disabled = false;
           });
-    },
+    }
 
     _computeAddButtonDisabled(newKey) {
       return !newKey.length;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSshEditor.is, GrSshEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor_test.html b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor_test.html
index d313f5a..912c1fd 100644
--- a/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-ssh-editor/gr-ssh-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-ssh-editor</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.html b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.html
index 360ea2d..b1ecb2e 100644
--- a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.html
+++ b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.html
@@ -24,7 +24,9 @@
 
 <dom-module id="gr-watched-projects-editor">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="gr-form-styles">
       #watchedProjects .notifType {
         text-align: center;
diff --git a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.js b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.js
index a40094d..f96aa76 100644
--- a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.js
+++ b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor.js
@@ -25,34 +25,38 @@
     {name: 'Abandons', key: 'notify_abandoned_changes'},
   ];
 
-  Polymer({
-    is: 'gr-watched-projects-editor',
+  class GrWatchedProjectsEditor extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-watched-projects-editor'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        value: false,
-        notify: true,
-      },
-
-      _projects: Array,
-      _projectsToRemove: {
-        type: Array,
-        value() { return []; },
-      },
-      _query: {
-        type: Function,
-        value() {
-          return this._getProjectSuggestions.bind(this);
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          value: false,
+          notify: true,
         },
-      },
-    },
+
+        _projects: Array,
+        _projectsToRemove: {
+          type: Array,
+          value() { return []; },
+        },
+        _query: {
+          type: Function,
+          value() {
+            return this._getProjectSuggestions.bind(this);
+          },
+        },
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getWatchedProjects().then(projs => {
         this._projects = projs;
       });
-    },
+    }
 
     save() {
       let deletePromise;
@@ -72,19 +76,19 @@
             this._projectsToRemove = [];
             this.hasUnsavedChanges = false;
           });
-    },
+    }
 
     _getTypes() {
       return NOTIFICATION_TYPES;
-    },
+    }
 
     _getTypeCount() {
       return this._getTypes().length;
-    },
+    }
 
     _computeCheckboxChecked(project, key) {
       return project.hasOwnProperty(key);
-    },
+    }
 
     _getProjectSuggestions(input) {
       return this.$.restAPI.getSuggestedProjects(input)
@@ -99,7 +103,7 @@
             }
             return projects;
           });
-    },
+    }
 
     _handleRemoveProject(e) {
       const el = Polymer.dom(e).localTarget;
@@ -108,7 +112,7 @@
       this.splice('_projects', index, 1);
       this.push('_projectsToRemove', project);
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _canAddProject(project, text, filter) {
       if ((!project || !project.id) && !text) { return false; }
@@ -126,7 +130,7 @@
       }
 
       return true;
-    },
+    }
 
     _getNewProjectIndex(name, filter) {
       let i;
@@ -138,7 +142,7 @@
         }
       }
       return i;
-    },
+    }
 
     _handleAddProject() {
       const newProject = this.$.newProject.value;
@@ -158,7 +162,7 @@
       this.$.newProject.clear();
       this.$.newFilter.bindValue = '';
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleCheckboxChange(e) {
       const el = Polymer.dom(e).localTarget;
@@ -167,11 +171,13 @@
       const checked = el.checked;
       this.set(['_projects', index, key], !!checked);
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleNotifCellClick(e) {
       const checkbox = Polymer.dom(e.target).querySelector('input');
       if (checkbox) { checkbox.click(); }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrWatchedProjectsEditor.is, GrWatchedProjectsEditor);
 })();
diff --git a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor_test.html b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor_test.html
index 7a238ec..4bdb00f 100644
--- a/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-watched-projects-editor/gr-watched-projects-editor_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-settings-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip.js b/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip.js
index 10c876d..27b1cc4 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-chip/gr-account-chip.js
@@ -14,13 +14,18 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-account-chip',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrAccountChip extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-chip'; }
     /**
      * Fired to indicate a key was pressed while this chip was focused.
      *
@@ -34,51 +39,52 @@
      * @event remove
      */
 
-    properties: {
-      account: Object,
-      additionalText: String,
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      removable: {
-        type: Boolean,
-        value: false,
-      },
-      showAvatar: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-      transparentBackground: {
-        type: Boolean,
-        value: false,
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        account: Object,
+        additionalText: String,
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        removable: {
+          type: Boolean,
+          value: false,
+        },
+        showAvatar: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+        transparentBackground: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     ready() {
+      super.ready();
       this._getHasAvatars().then(hasAvatars => {
         this.showAvatar = hasAvatars;
       });
-    },
+    }
 
     _getBackgroundClass(transparent) {
       return transparent ? 'transparentBackground' : '';
-    },
+    }
 
     _handleRemoveTap(e) {
       e.preventDefault();
       this.fire('remove', {account: this.account});
-    },
+    }
 
     _getHasAvatars() {
       return this.$.restAPI.getConfig().then(cfg => {
         return Promise.resolve(!!(cfg && cfg.plugin && cfg.plugin.has_avatars));
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountChip.is, GrAccountChip);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.html b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.html
index ae656fd..992ea8407 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.html
@@ -40,7 +40,8 @@
         on-commit="_handleInputCommit"
         clear-on-commit
         warn-uncommitted
-        text="{{_inputText}}">
+        text="{{_inputText}}"
+        vertical-offset="24">
     </gr-autocomplete>
   </template>
   <script src="gr-account-entry.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.js b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.js
index 92836a8..0ed3f19 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry.js
@@ -21,9 +21,10 @@
    * gr-account-entry is an element for entering account
    * and/or group with autocomplete support.
    */
-  Polymer({
-    is: 'gr-account-entry',
-
+  class GrAccountEntry extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-account-entry'; }
     /**
      * Fired when an account is entered.
      *
@@ -37,65 +38,70 @@
      *
      * @event account-text-changed
      */
-    properties: {
-      allowAnyInput: Boolean,
-      borderless: Boolean,
-      placeholder: String,
 
-      // suggestFrom = 0 to enable default suggestions.
-      suggestFrom: {
-        type: Number,
-        value: 0,
-      },
+    static get properties() {
+      return {
+        allowAnyInput: Boolean,
+        borderless: Boolean,
+        placeholder: String,
 
-      /** @type {!function(string): !Promise<Array<{name, value}>>} */
-      querySuggestions: {
-        type: Function,
-        notify: true,
-        value() {
-          return input => Promise.resolve([]);
+        // suggestFrom = 0 to enable default suggestions.
+        suggestFrom: {
+          type: Number,
+          value: 0,
         },
-      },
 
-      _config: Object,
-      /** The value of the autocomplete entry. */
-      _inputText: {
-        type: String,
-        observer: '_inputTextChanged',
-      },
+        /** @type {!function(string): !Promise<Array<{name, value}>>} */
+        querySuggestions: {
+          type: Function,
+          notify: true,
+          value() {
+            return input => Promise.resolve([]);
+          },
+        },
 
-    },
+        _config: Object,
+        /** The value of the autocomplete entry. */
+        _inputText: {
+          type: String,
+          observer: '_inputTextChanged',
+        },
+
+      };
+    }
 
     get focusStart() {
       return this.$.input.focusStart;
-    },
+    }
 
     focus() {
       this.$.input.focus();
-    },
+    }
 
     clear() {
       this.$.input.clear();
-    },
+    }
 
     setText(text) {
       this.$.input.setText(text);
-    },
+    }
 
     getText() {
       return this.$.input.text;
-    },
+    }
 
     _handleInputCommit(e) {
       this.fire('add', {value: e.detail.value});
       this.$.input.focus();
-    },
+    }
 
     _inputTextChanged(text) {
       if (text.length && this.allowAnyInput) {
         this.dispatchEvent(new CustomEvent(
-                'account-text-changed', {bubbles: true, composed: true}));
+            'account-text-changed', {bubbles: true, composed: true}));
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountEntry.is, GrAccountEntry);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_test.html b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_test.html
index 59792a7..0bac7e0 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-entry/gr-account-entry_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-entry</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -92,7 +92,7 @@
 
     test('account-text-changed not fired when input text changed without ' +
         'allowAnyInput', () => {
-          // Spy on query, as that is called when _updateSuggestions proceeds.
+      // Spy on query, as that is called when _updateSuggestions proceeds.
       const changeStub = sandbox.stub();
       element.querySuggestions = input => Promise.resolve([]);
       element.addEventListener('account-text-changed', changeStub);
diff --git a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label.js b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label.js
index 418d2ea..3d96421 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label.js
@@ -17,58 +17,65 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-account-label',
+  /**
+    * @appliesMixin Gerrit.DisplayNameMixin
+    * @appliesMixin Gerrit.TooltipMixin
+    */
+  class GrAccountLabel extends Polymer.mixinBehaviors( [
+    Gerrit.DisplayNameBehavior,
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-label'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * @type {{ name: string, status: string }}
        */
-      account: Object,
-      avatarImageSize: {
-        type: Number,
-        value: 32,
-      },
-      title: {
-        type: String,
-        reflectToAttribute: true,
-        computed: '_computeAccountTitle(account, additionalText)',
-      },
-      additionalText: String,
-      hasTooltip: {
-        type: Boolean,
-        reflectToAttribute: true,
-        computed: '_computeHasTooltip(account)',
-      },
-      hideAvatar: {
-        type: Boolean,
-        value: false,
-      },
-      _serverConfig: {
-        type: Object,
-        value: null,
-      },
-    },
-
-    behaviors: [
-      Gerrit.DisplayNameBehavior,
-      Gerrit.TooltipBehavior,
-    ],
+        account: Object,
+        avatarImageSize: {
+          type: Number,
+          value: 32,
+        },
+        title: {
+          type: String,
+          reflectToAttribute: true,
+          computed: '_computeAccountTitle(account, additionalText)',
+        },
+        additionalText: String,
+        hasTooltip: {
+          type: Boolean,
+          reflectToAttribute: true,
+          computed: '_computeHasTooltip(account)',
+        },
+        hideAvatar: {
+          type: Boolean,
+          value: false,
+        },
+        _serverConfig: {
+          type: Object,
+          value: null,
+        },
+      };
+    }
 
     ready() {
+      super.ready();
       if (!this.additionalText) { this.additionalText = ''; }
       this.$.restAPI.getConfig()
           .then(config => { this._serverConfig = config; });
-    },
+    }
 
     _computeName(account, config) {
       return this.getUserName(config, account, false);
-    },
+    }
 
     _computeStatusTextLength(account, config) {
       // 35 as the max length of the name + status
       return Math.max(10, 35 - this._computeName(account, config).length);
-    },
+    }
 
     _computeAccountTitle(account, tooltip) {
       // Polymer 2: check for undefined
@@ -98,12 +105,12 @@
       }
 
       return result;
-    },
+    }
 
     _computeShowEmailClass(account) {
       if (!account || account.name || !account.email) { return ''; }
       return 'showEmail';
-    },
+    }
 
     _computeEmailStr(account) {
       if (!account || !account.email) {
@@ -113,11 +120,13 @@
         return '(' + account.email + ')';
       }
       return account.email;
-    },
+    }
 
     _computeHasTooltip(account) {
       // If an account has loaded to fire this method, then set to true.
       return !!account;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountLabel.is, GrAccountLabel);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_test.html b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_test.html
index 740dfcf..f369ae2 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-label/gr-account-label_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-label</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -64,19 +64,21 @@
     });
 
     test('computed fields', () => {
-      assert.equal(element._computeAccountTitle(
-          {
+      assert.equal(
+          element._computeAccountTitle({
             name: 'Andrew Bonventre',
             email: 'andybons+gerrit@gmail.com',
           }, /* additionalText= */ ''),
           'Andrew Bonventre <andybons+gerrit@gmail.com>');
 
-      assert.equal(element._computeAccountTitle(
-          {name: 'Andrew Bonventre'}, /* additionalText= */ ''),
+      assert.equal(
+          element._computeAccountTitle({
+            name: 'Andrew Bonventre',
+          }, /* additionalText= */ ''),
           'Andrew Bonventre');
 
-      assert.equal(element._computeAccountTitle(
-          {
+      assert.equal(
+          element._computeAccountTitle({
             email: 'andybons+gerrit@gmail.com',
           }, /* additionalText= */ ''),
           'Anonymous <andybons+gerrit@gmail.com>');
@@ -94,9 +96,9 @@
 
       assert.equal(element._computeShowEmailClass(
           {name: 'Andrew Bonventre'},
-          /* additionalText= */ '',
+          /* additionalText= */ ''
       ),
-          '');
+      '');
 
       assert.equal(element._computeShowEmailClass(undefined), '');
 
diff --git a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link.js b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link.js
index faaf9c3..0764669 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link.js
@@ -17,27 +17,34 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-account-link',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    */
+  class GrAccountLink extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-link'; }
 
-    properties: {
-      additionalText: String,
-      account: Object,
-      avatarImageSize: {
-        type: Number,
-        value: 32,
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-    ],
+    static get properties() {
+      return {
+        additionalText: String,
+        account: Object,
+        avatarImageSize: {
+          type: Number,
+          value: 32,
+        },
+      };
+    }
 
     _computeOwnerLink(account) {
       if (!account) { return; }
       return Gerrit.Nav.getUrlForOwner(
           account.email || account.username || account.name ||
           account._account_id);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountLink.is, GrAccountLink);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_test.html b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_test.html
index 134c579..e41304f 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-link/gr-account-link_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-link</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.html b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.html
index 2ce608be..6103d6f 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.html
@@ -66,7 +66,6 @@
         borderless
         hidden$="[[_computeEntryHidden(maxCount, accounts.*, readonly)]]"
         id="entry"
-        change="[[change]]"
         placeholder="[[placeholder]]"
         on-add="_handleAdd"
         on-input-keydown="_handleInputKeydown"
diff --git a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.js b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.js
index 5f1d41a..3caec32 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.js
+++ b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list.js
@@ -19,97 +19,116 @@
 
   const VALID_EMAIL_ALERT = 'Please input a valid email.';
 
-  Polymer({
-    is: 'gr-account-list',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrAccountList extends Polymer.mixinBehaviors( [
+    // Used in the tests for gr-account-list and other elements tests.
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-account-list'; }
     /**
      * Fired when user inputs an invalid email address.
      *
      * @event show-alert
      */
 
-    properties: {
-      accounts: {
-        type: Array,
-        value() { return []; },
-        notify: true,
-      },
-      change: Object,
-      filter: Function,
-      placeholder: String,
-      disabled: {
-        type: Function,
-        value: false,
-      },
-
-      /**
-       * Returns suggestions and convert them to list item
-       * @type {Gerrit.GrSuggestionsProvider}
-       */
-      suggestionsProvider: {
-        type: Object,
-      },
-
-      /**
-       * Needed for template checking since value is initially set to null.
-       * @type {?Object} */
-      pendingConfirmation: {
-        type: Object,
-        value: null,
-        notify: true,
-      },
-      readonly: {
-        type: Boolean,
-        value: false,
-      },
-      /**
-       * When true, allows for non-suggested inputs to be added.
-       */
-      allowAnyInput: {
-        type: Boolean,
-        value: false,
-      },
-
-      /**
-       * Array of values (groups/accounts) that are removable. When this prop is
-       * undefined, all values are removable.
-       */
-      removableValues: Array,
-      maxCount: {
-        type: Number,
-        value: 0,
-      },
-
-      /** Returns suggestion items
-      * @type {!function(string): Promise<Array<Gerrit.GrSuggestionItem>>}
-      */
-      _querySuggestions: {
-        type: Function,
-        value() {
-          return this._getSuggestions.bind(this);
+    static get properties() {
+      return {
+        accounts: {
+          type: Array,
+          value() { return []; },
+          notify: true,
         },
-      },
-    },
+        change: Object,
+        filter: Function,
+        placeholder: String,
+        disabled: {
+          type: Function,
+          value: false,
+        },
 
-    behaviors: [
-      // Used in the tests for gr-account-list and other elements tests.
-      Gerrit.FireBehavior,
-    ],
+        /**
+         * Returns suggestions and convert them to list item
+         * @type {Gerrit.GrSuggestionsProvider}
+         */
+        suggestionsProvider: {
+          type: Object,
+        },
 
-    listeners: {
-      remove: '_handleRemove',
-    },
+        /**
+         * Needed for template checking since value is initially set to null.
+         * @type {?Object}
+         */
+        pendingConfirmation: {
+          type: Object,
+          value: null,
+          notify: true,
+        },
+        readonly: {
+          type: Boolean,
+          value: false,
+        },
+        /**
+         * When true, allows for non-suggested inputs to be added.
+         */
+        allowAnyInput: {
+          type: Boolean,
+          value: false,
+        },
+
+        /**
+         * Array of values (groups/accounts) that are removable. When this prop is
+         * undefined, all values are removable.
+         */
+        removableValues: Array,
+        maxCount: {
+          type: Number,
+          value: 0,
+        },
+
+        /**
+         * Returns suggestion items
+         * @type {!function(string): Promise<Array<Gerrit.GrSuggestionItem>>}
+         */
+        _querySuggestions: {
+          type: Function,
+          value() {
+            return this._getSuggestions.bind(this);
+          },
+        },
+
+        /**
+         * Set to true to disable suggestions on empty input.
+         */
+        skipSuggestOnEmpty: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('remove',
+          e => this._handleRemove(e));
+    }
 
     get accountChips() {
       return Array.from(
           Polymer.dom(this.root).querySelectorAll('gr-account-chip'));
-    },
+    }
 
     get focusStart() {
       return this.$.entry.focusStart;
-    },
+    }
 
     _getSuggestions(input) {
+      if (this.skipSuggestOnEmpty && !input) {
+        return Promise.resolve([]);
+      }
       const provider = this.suggestionsProvider;
       if (!provider) {
         return Promise.resolve([]);
@@ -120,13 +139,13 @@
           suggestions = suggestions.filter(this.filter);
         }
         return suggestions.map(suggestion =>
-            provider.makeSuggestionItem(suggestion));
+          provider.makeSuggestionItem(suggestion));
       });
-    },
+    }
 
     _handleAdd(e) {
       this._addAccountItem(e.detail.value);
-    },
+    }
 
     _addAccountItem(item) {
       // Append new account or group to the accounts property. We add our own
@@ -162,14 +181,14 @@
       }
       this.pendingConfirmation = null;
       return true;
-    },
+    }
 
     confirmGroup(group) {
       group = Object.assign(
           {}, group, {confirmed: true, _pendingAdd: true, _group: true});
       this.push('accounts', group);
       this.pendingConfirmation = null;
-    },
+    }
 
     _computeChipClass(account) {
       const classes = [];
@@ -180,7 +199,7 @@
         classes.push('pendingAdd');
       }
       return classes.join(' ');
-    },
+    }
 
     _accountMatches(a, b) {
       if (a && b) {
@@ -192,7 +211,7 @@
         }
       }
       return a === b;
-    },
+    }
 
     _computeRemovable(account, readonly) {
       if (readonly) { return false; }
@@ -205,13 +224,13 @@
         return !!account._pendingAdd;
       }
       return true;
-    },
+    }
 
     _handleRemove(e) {
       const toRemove = e.detail.account;
       this._removeAccount(toRemove);
       this.$.entry.focus();
-    },
+    }
 
     _removeAccount(toRemove) {
       if (!toRemove || !this._computeRemovable(toRemove, this.readonly)) {
@@ -231,12 +250,12 @@
         }
       }
       console.warn('received remove event for missing account', toRemove);
-    },
+    }
 
     _getNativeInput(paperInput) {
       // In Polymer 2 inputElement isn't nativeInput anymore
       return paperInput.$.nativeInput || paperInput.inputElement;
-    },
+    }
 
     _handleInputKeydown(e) {
       const input = this._getNativeInput(e.detail.input);
@@ -254,7 +273,7 @@
           }
           break;
       }
-    },
+    }
 
     _handleChipKeydown(e) {
       const chip = e.target;
@@ -292,7 +311,7 @@
           }
           break;
       }
-    },
+    }
 
     /**
      * Submit the text of the entry as a reviewer value, if it exists. If it is
@@ -308,7 +327,7 @@
       const wasSubmitted = this._addAccountItem(text);
       if (wasSubmitted) { this.$.entry.clear(); }
       return wasSubmitted;
-    },
+    }
 
     additions() {
       return this.accounts.filter(account => {
@@ -320,10 +339,12 @@
           return {account};
         }
       });
-    },
+    }
 
     _computeEntryHidden(maxCount, accountsRecord, readonly) {
       return (maxCount && maxCount <= accountsRecord.base.length) || readonly;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAccountList.is, GrAccountList);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_test.html b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_test.html
index 6f265e7..7fea243 100644
--- a/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-account-list/gr-account-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-account-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -44,6 +44,7 @@
       return item;
     }
   }
+
   suite('gr-account-list tests', () => {
     let _nextAccountId = 0;
     const makeAccount = function() {
@@ -186,7 +187,6 @@
         };
       });
 
-
       element._getSuggestions().then(suggestions => {
         // Default is no filtering.
         assert.equal(suggestions.length, 3);
@@ -224,7 +224,6 @@
       assert.isFalse(element._computeRemovable(existingAccount1, false));
       assert.isTrue(element._computeRemovable(newAccount, false));
 
-
       element.removableValues = [existingAccount1];
       assert.isTrue(element._computeRemovable(existingAccount1, false));
       assert.isTrue(element._computeRemovable(newAccount, false));
@@ -383,6 +382,57 @@
       });
     });
 
+    test('suggestion on empty', done => {
+      element.skipSuggestOnEmpty = false;
+      const suggestions = [
+        {
+          email: 'abc@example.com',
+          text: 'abcd',
+        },
+        {
+          email: 'qwe@example.com',
+          text: 'qwer',
+        },
+      ];
+      const getSuggestionsStub =
+          sandbox.stub(suggestionsProvider, 'getSuggestions')
+              .returns(Promise.resolve(suggestions));
+
+      const makeSuggestionItemStub =
+          sandbox.stub(suggestionsProvider, 'makeSuggestionItem', item => item);
+
+      const input = element.$.entry.$.input;
+
+      input.text = '';
+      MockInteractions.focus(input.$.input);
+      input.noDebounce = true;
+      flushAsynchronousOperations();
+      flush(() => {
+        assert.isTrue(getSuggestionsStub.calledOnce);
+        assert.equal(getSuggestionsStub.lastCall.args[0], '');
+        assert.equal(makeSuggestionItemStub.getCalls().length, 2);
+        done();
+      });
+    });
+
+    test('skip suggestion on empty', done => {
+      element.skipSuggestOnEmpty = true;
+      const getSuggestionsStub =
+          sandbox.stub(suggestionsProvider, 'getSuggestions')
+              .returns(Promise.resolve([]));
+
+      const input = element.$.entry.$.input;
+
+      input.text = '';
+      MockInteractions.focus(input.$.input);
+      input.noDebounce = true;
+      flushAsynchronousOperations();
+      flush(() => {
+        assert.isTrue(getSuggestionsStub.notCalled);
+        done();
+      });
+    });
+
     suite('allowAnyInput', () => {
       setup(() => {
         element.allowAnyInput = true;
diff --git a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert.js b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert.js
index e7c8b2c..433a57b 100644
--- a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert.js
+++ b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert.js
@@ -17,46 +17,51 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-alert',
-
+  class GrAlert extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-alert'; }
     /**
      * Fired when the action button is pressed.
      *
      * @event action
      */
 
-    properties: {
-      text: String,
-      actionText: String,
-      shown: {
-        type: Boolean,
-        value: true,
-        readOnly: true,
-        reflectToAttribute: true,
-      },
-      toast: {
-        type: Boolean,
-        value: true,
-        reflectToAttribute: true,
-      },
+    static get properties() {
+      return {
+        text: String,
+        actionText: String,
+        shown: {
+          type: Boolean,
+          value: true,
+          readOnly: true,
+          reflectToAttribute: true,
+        },
+        toast: {
+          type: Boolean,
+          value: true,
+          reflectToAttribute: true,
+        },
 
-      _hideActionButton: Boolean,
-      _boundTransitionEndHandler: {
-        type: Function,
-        value() { return this._handleTransitionEnd.bind(this); },
-      },
-      _actionCallback: Function,
-    },
+        _hideActionButton: Boolean,
+        _boundTransitionEndHandler: {
+          type: Function,
+          value() { return this._handleTransitionEnd.bind(this); },
+        },
+        _actionCallback: Function,
+      };
+    }
 
     attached() {
+      super.attached();
       this.addEventListener('transitionend', this._boundTransitionEndHandler);
-    },
+    }
 
     detached() {
+      super.detached();
       this.removeEventListener('transitionend',
           this._boundTransitionEndHandler);
-    },
+    }
 
     show(text, opt_actionText, opt_actionCallback) {
       this.text = text;
@@ -65,31 +70,33 @@
       this._actionCallback = opt_actionCallback;
       Gerrit.getRootElement().appendChild(this);
       this._setShown(true);
-    },
+    }
 
     hide() {
       this._setShown(false);
       if (this._hasZeroTransitionDuration()) {
         Gerrit.getRootElement().removeChild(this);
       }
-    },
+    }
 
     _hasZeroTransitionDuration() {
       const style = window.getComputedStyle(this);
       // transitionDuration is always given in seconds.
       const duration = Math.round(parseFloat(style.transitionDuration) * 100);
       return duration === 0;
-    },
+    }
 
     _handleTransitionEnd(e) {
       if (this.shown) { return; }
 
       Gerrit.getRootElement().removeChild(this);
-    },
+    }
 
     _handleActionTap(e) {
       e.preventDefault();
       if (this._actionCallback) { this._actionCallback(); }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAlert.is, GrAlert);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_test.html b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_test.html
index 2338d55..bfcc431 100644
--- a/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-alert/gr-alert_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-alert</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.html b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.html
index 9208068..cf32e28 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.html
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.html
@@ -22,6 +22,7 @@
 <link rel="import" href="/bower_components/iron-dropdown/iron-dropdown.html">
 <link rel="import" href="/bower_components/iron-fit-behavior/iron-fit-behavior.html">
 <link rel="import" href="../../shared/gr-cursor-manager/gr-cursor-manager.html">
+<script src="../../../types/polymer-behaviors.js"></script>
 <script src="../../../scripts/rootElement.js"></script>
 <link rel="import" href="../../../styles/shared-styles.html">
 
@@ -59,6 +60,7 @@
       .dropdown-content {
         background: var(--dropdown-background-color);
         box-shadow: rgba(0, 0, 0, 0.3) 0 1px 3px;
+        border-radius: var(--border-radius);
         max-height: 50vh;
         overflow: auto;
       }
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.js b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.js
index b8c76ff..707c426 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.js
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.js
@@ -17,9 +17,19 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-autocomplete-dropdown',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Polymer.IronFitMixin
+    */
+  class GrAutocompleteDropdown extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Polymer.IronFitBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-autocomplete-dropdown'; }
     /**
      * Fired when the dropdown is closed.
      *
@@ -32,57 +42,55 @@
      * @event item-selected
      */
 
-    properties: {
-      index: Number,
-      isHidden: {
-        type: Boolean,
-        value: true,
-        reflectToAttribute: true,
-      },
-      verticalOffset: {
-        type: Number,
-        value: null,
-      },
-      horizontalOffset: {
-        type: Number,
-        value: null,
-      },
-      suggestions: {
-        type: Array,
-        value: () => [],
-        observer: '_resetCursorStops',
-      },
-      _suggestionEls: Array,
-    },
+    static get properties() {
+      return {
+        index: Number,
+        isHidden: {
+          type: Boolean,
+          value: true,
+          reflectToAttribute: true,
+        },
+        verticalOffset: {
+          type: Number,
+          value: null,
+        },
+        horizontalOffset: {
+          type: Number,
+          value: null,
+        },
+        suggestions: {
+          type: Array,
+          value: () => [],
+          observer: '_resetCursorStops',
+        },
+        _suggestionEls: Array,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Polymer.IronFitBehavior,
-    ],
-
-    keyBindings: {
-      up: '_handleUp',
-      down: '_handleDown',
-      enter: '_handleEnter',
-      esc: '_handleEscape',
-      tab: '_handleTab',
-    },
+    get keyBindings() {
+      return {
+        up: '_handleUp',
+        down: '_handleDown',
+        enter: '_handleEnter',
+        esc: '_handleEscape',
+        tab: '_handleTab',
+      };
+    }
 
     close() {
       this.isHidden = true;
-    },
+    }
 
     open() {
       this.isHidden = false;
       this._resetCursorStops();
       // Refit should run after we call Polymer.flush inside _resetCursorStops
       this.refit();
-    },
+    }
 
     getCurrentText() {
       return this.getCursorTarget().dataset.value;
-    },
+    }
 
     _handleUp(e) {
       if (!this.isHidden) {
@@ -90,7 +98,7 @@
         e.stopPropagation();
         this.cursorUp();
       }
-    },
+    }
 
     _handleDown(e) {
       if (!this.isHidden) {
@@ -98,19 +106,19 @@
         e.stopPropagation();
         this.cursorDown();
       }
-    },
+    }
 
     cursorDown() {
       if (!this.isHidden) {
         this.$.cursor.next();
       }
-    },
+    }
 
     cursorUp() {
       if (!this.isHidden) {
         this.$.cursor.previous();
       }
-    },
+    }
 
     _handleTab(e) {
       e.preventDefault();
@@ -119,7 +127,7 @@
         trigger: 'tab',
         selected: this.$.cursor.target,
       });
-    },
+    }
 
     _handleEnter(e) {
       e.preventDefault();
@@ -128,12 +136,12 @@
         trigger: 'enter',
         selected: this.$.cursor.target,
       });
-    },
+    }
 
     _handleEscape() {
       this._fireClose();
       this.close();
-    },
+    }
 
     _handleClickItem(e) {
       e.preventDefault();
@@ -147,15 +155,15 @@
         trigger: 'click',
         selected,
       });
-    },
+    }
 
     _fireClose() {
       this.fire('dropdown-closed');
-    },
+    }
 
     getCursorTarget() {
       return this.$.cursor.target;
-    },
+    }
 
     _resetCursorStops() {
       if (this.suggestions.length > 0) {
@@ -168,14 +176,16 @@
       } else {
         this._suggestionEls = [];
       }
-    },
+    }
 
     _resetCursorIndex() {
       this.$.cursor.setCursorAtIndex(0);
-    },
+    }
 
     _computeLabelClass(item) {
       return item.label ? '' : 'hide';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAutocompleteDropdown.is, GrAutocompleteDropdown);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_test.html b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_test.html
index a7b59d7..5f2ce94 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-autocomplete-dropdown</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.html b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.html
index c9d12ce..e47b661 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.html
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.html
@@ -36,13 +36,14 @@
         margin: 0 var(--spacing-xs);
         vertical-align: top;
       }
-      paper-input:not(.borderless) {
-        border: 1px solid var(--border-color);
+      paper-input.borderless {
+        border: none;
+        padding: 0;
       }
       paper-input {
-        height: var(--line-height-normal);
-        width: 100%;
-        @apply --gr-autocomplete;
+        border: 1px solid var(--border-color);
+        border-radius: var(--border-radius);
+        padding: var(--spacing-s);
         --paper-input-container: {
           padding: 0;
         };
@@ -50,13 +51,25 @@
           font-size: var(--font-size-normal);
           line-height: var(--line-height-normal);
         };
+        /* This is a hack for not being able to set height:0 on the underline
+           of a paper-input 2.2.3 element. All the underline fixes below only
+           actually work in 3.x.x, so the height must be adjusted directly as
+           a workaround until we are on Polymer 3. */
+        height: var(--line-height-normal);
+        --paper-input-container-underline-height: 0;
+        --paper-input-container-underline-wrapper-height: 0;
+        --paper-input-container-underline-focus-height: 0;
+        --paper-input-container-underline-legacy-height: 0;
         --paper-input-container-underline: {
+          height: 0;
           display: none;
         };
         --paper-input-container-underline-focus: {
+          height: 0;
           display: none;
         };
         --paper-input-container-underline-disabled: {
+          height: 0;
           display: none;
         };
       }
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.js b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.js
index da16e2b..3a60255 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.js
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.js
@@ -20,9 +20,17 @@
   const TOKENIZE_REGEX = /(?:[^\s"]+|"[^"]*")+/g;
   const DEBOUNCE_WAIT_MS = 200;
 
-  Polymer({
-    is: 'gr-autocomplete',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrAutocomplete extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-autocomplete'; }
     /**
      * Fired when a value is chosen.
      *
@@ -42,9 +50,10 @@
      * @event input-keydown
      */
 
-    properties: {
+    static get properties() {
+      return {
 
-      /**
+        /**
        * Query for requesting autocomplete suggestions. The function should
        * accept the input as a string parameter and return a promise. The
        * promise yields an array of suggestion objects with "name", "label",
@@ -55,170 +64,174 @@
        *
        * @type {function(string): Promise<?>}
        */
-      query: {
-        type: Function,
-        value() {
-          return function() {
-            return Promise.resolve([]);
-          };
+        query: {
+          type: Function,
+          value() {
+            return function() {
+              return Promise.resolve([]);
+            };
+          },
         },
-      },
 
-      /**
-       * The number of characters that must be typed before suggestions are
-       * made. If threshold is zero, default suggestions are enabled.
-       */
-      threshold: {
-        type: Number,
-        value: 1,
-      },
+        /**
+         * The number of characters that must be typed before suggestions are
+         * made. If threshold is zero, default suggestions are enabled.
+         */
+        threshold: {
+          type: Number,
+          value: 1,
+        },
 
-      allowNonSuggestedValues: Boolean,
-      borderless: Boolean,
-      disabled: Boolean,
-      showSearchIcon: {
-        type: Boolean,
-        value: false,
-      },
-      // Vertical offset needed for a 1em font-size with no vertical padding.
-      // Inputs with additional padding will need to increase vertical offset.
-      verticalOffset: {
-        type: Number,
-        value: 20,
-      },
+        allowNonSuggestedValues: Boolean,
+        borderless: Boolean,
+        disabled: Boolean,
+        showSearchIcon: {
+          type: Boolean,
+          value: false,
+        },
+        /**
+         * Vertical offset needed for an element with 20px line-height, 4px
+         * padding and 1px border (30px height total). Plus 1px spacing between
+         * input and dropdown. Inputs with different line-height or padding will
+         * need to tweak vertical offset.
+         */
+        verticalOffset: {
+          type: Number,
+          value: 31,
+        },
 
-      text: {
-        type: String,
-        value: '',
-        notify: true,
-      },
+        text: {
+          type: String,
+          value: '',
+          notify: true,
+        },
 
-      placeholder: String,
+        placeholder: String,
 
-      clearOnCommit: {
-        type: Boolean,
-        value: false,
-      },
+        clearOnCommit: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
-       * When true, tab key autocompletes but does not fire the commit event.
-       * When false, tab key not caught, and focus is removed from the element.
-       * See Issue 4556, Issue 6645.
-       */
-      tabComplete: {
-        type: Boolean,
-        value: false,
-      },
+        /**
+         * When true, tab key autocompletes but does not fire the commit event.
+         * When false, tab key not caught, and focus is removed from the element.
+         * See Issue 4556, Issue 6645.
+         */
+        tabComplete: {
+          type: Boolean,
+          value: false,
+        },
 
-      value: {
-        type: String,
-        notify: true,
-      },
+        value: {
+          type: String,
+          notify: true,
+        },
 
-      /**
+        /**
        * Multi mode appends autocompleted entries to the value.
        * If false, autocompleted entries replace value.
        */
-      multi: {
-        type: Boolean,
-        value: false,
-      },
+        multi: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * When true and uncommitted text is left in the autocomplete input after
        * blurring, the text will appear red.
        */
-      warnUncommitted: {
-        type: Boolean,
-        value: false,
-      },
+        warnUncommitted: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * When true, querying for suggestions is not debounced w/r/t keypresses
        */
-      noDebounce: {
-        type: Boolean,
-        value: false,
-      },
+        noDebounce: {
+          type: Boolean,
+          value: false,
+        },
 
-      /** @type {?} */
-      _suggestions: {
-        type: Array,
-        value() { return []; },
-      },
+        /** @type {?} */
+        _suggestions: {
+          type: Array,
+          value() { return []; },
+        },
 
-      _suggestionEls: {
-        type: Array,
-        value() { return []; },
-      },
+        _suggestionEls: {
+          type: Array,
+          value() { return []; },
+        },
 
-      _index: Number,
-      _disableSuggestions: {
-        type: Boolean,
-        value: false,
-      },
-      _focused: {
-        type: Boolean,
-        value: false,
-      },
+        _index: Number,
+        _disableSuggestions: {
+          type: Boolean,
+          value: false,
+        },
+        _focused: {
+          type: Boolean,
+          value: false,
+        },
 
-      /** The DOM element of the selected suggestion. */
-      _selected: Object,
-    },
+        /** The DOM element of the selected suggestion. */
+        _selected: Object,
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    observers: [
-      '_maybeOpenDropdown(_suggestions, _focused)',
-      '_updateSuggestions(text, threshold, noDebounce)',
-    ],
+    static get observers() {
+      return [
+        '_maybeOpenDropdown(_suggestions, _focused)',
+        '_updateSuggestions(text, threshold, noDebounce)',
+      ];
+    }
 
     get _nativeInput() {
       // In Polymer 2 inputElement isn't nativeInput anymore
       return this.$.input.$.nativeInput || this.$.input.inputElement;
-    },
+    }
 
     attached() {
+      super.attached();
       this.listen(document.body, 'click', '_handleBodyClick');
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(document.body, 'click', '_handleBodyClick');
       this.cancelDebouncer('update-suggestions');
-    },
+    }
 
     get focusStart() {
       return this.$.input;
-    },
+    }
 
     focus() {
       this._nativeInput.focus();
-    },
+    }
 
     selectAll() {
       const nativeInputElement = this._nativeInput;
       if (!this.$.input.value) { return; }
       nativeInputElement.setSelectionRange(0, this.$.input.value.length);
-    },
+    }
 
     clear() {
       this.text = '';
-    },
+    }
 
     _handleItemSelect(e) {
       // Let _handleKeydown deal with keyboard interaction.
       if (e.detail.trigger !== 'click') { return; }
       this._selected = e.detail.selected;
       this._commit();
-    },
+    }
 
     get _inputElement() {
       // Polymer2: this.$ can be undefined when this is first evaluated.
       return this.$ && this.$.input;
-    },
+    }
 
     /**
      * Set the text of the input without triggering the suggestion dropdown.
@@ -228,7 +241,7 @@
       this._disableSuggestions = true;
       this.text = text;
       this._disableSuggestions = false;
-    },
+    }
 
     _onInputFocus() {
       this._focused = true;
@@ -236,14 +249,14 @@
       this.$.input.classList.remove('warnUncommitted');
       // Needed so that --paper-input-container-input updated style is applied.
       this.updateStyles();
-    },
+    }
 
     _onInputBlur() {
       this.$.input.classList.toggle('warnUncommitted',
           this.warnUncommitted && this.text.length && !this._focused);
       // Needed so that --paper-input-container-input updated style is applied.
       this.updateStyles();
-    },
+    }
 
     _updateSuggestions(text, threshold, noDebounce) {
       // Polymer 2: check for undefined
@@ -280,18 +293,18 @@
       } else {
         this.debounce('update-suggestions', update, DEBOUNCE_WAIT_MS);
       }
-    },
+    }
 
     _maybeOpenDropdown(suggestions, focused) {
       if (suggestions.length > 0 && focused) {
         return this.$.suggestions.open();
       }
       return this.$.suggestions.close();
-    },
+    }
 
     _computeClass(borderless) {
       return borderless ? 'borderless' : '';
-    },
+    }
 
     /**
      * _handleKeydown used for key handling in the this.$.input AND all child
@@ -338,7 +351,7 @@
           this._suggestions = [];
       }
       this.fire('input-keydown', {keyCode: e.keyCode, input: this.$.input});
-    },
+    }
 
     _cancel() {
       if (this._suggestions.length) {
@@ -346,7 +359,7 @@
       } else {
         this.fire('cancel');
       }
-    },
+    }
 
     /**
      * @param {boolean=} opt_tabComplete
@@ -358,7 +371,7 @@
 
       this._selected = this.$.suggestions.getCursorTarget();
       this._commit(opt_tabComplete);
-    },
+    }
 
     _updateValue(suggestion, suggestions) {
       if (!suggestion) { return; }
@@ -372,7 +385,7 @@
       } else {
         this.value = completed;
       }
-    },
+    }
 
     _handleBodyClick(e) {
       const eventPath = Polymer.dom(e).path;
@@ -382,13 +395,13 @@
         }
       }
       this._focused = false;
-    },
+    }
 
     _handleSuggestionTap(e) {
       e.stopPropagation();
       this.$.cursor.setCursor(e.target);
       this._commit();
-    },
+    }
 
     /**
      * Commits the suggestion, optionally firing the commit event.
@@ -424,10 +437,12 @@
       }
 
       this._textChangedSinceCommit = false;
-    },
+    }
 
     _computeShowSearchIconClass(showSearchIcon) {
       return showSearchIcon ? 'showSearchIcon' : '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAutocomplete.is, GrAutocomplete);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_test.html b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_test.html
index ea1fd50..39329e5 100644
--- a/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reviewer-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -335,7 +335,7 @@
     });
 
     test('vertical offset overridden by param if it exists', () => {
-      assert.equal(element.$.suggestions.verticalOffset, 20);
+      assert.equal(element.$.suggestions.verticalOffset, 31);
       element.verticalOffset = 30;
       assert.equal(element.$.suggestions.verticalOffset, 30);
     });
diff --git a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar.js b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar.js
index bf56382..e57ba33 100644
--- a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar.js
+++ b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar.js
@@ -17,29 +17,35 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-avatar',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    */
+  class GrAvatar extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-avatar'; }
 
-    properties: {
-      account: {
-        type: Object,
-        observer: '_accountChanged',
-      },
-      imageSize: {
-        type: Number,
-        value: 16,
-      },
-      _hasAvatars: {
-        type: Boolean,
-        value: false,
-      },
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-    ],
+    static get properties() {
+      return {
+        account: {
+          type: Object,
+          observer: '_accountChanged',
+        },
+        imageSize: {
+          type: Number,
+          value: 16,
+        },
+        _hasAvatars: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       Promise.all([
         this._getConfig(),
         Gerrit.awaitPluginsLoaded(),
@@ -48,15 +54,15 @@
 
         this._updateAvatarURL();
       });
-    },
+    }
 
     _getConfig() {
       return this.$.restAPI.getConfig();
-    },
+    }
 
     _accountChanged(account) {
       this._updateAvatarURL();
-    },
+    }
 
     _updateAvatarURL() {
       if (!this._hasAvatars || !this.account) {
@@ -69,12 +75,12 @@
       if (url) {
         this.style.backgroundImage = 'url("' + url + '")';
       }
-    },
+    }
 
     _getAccounts(account) {
       return account._account_id || account.email || account.username ||
           account.name;
-    },
+    }
 
     _buildAvatarURL(account) {
       if (!account) { return ''; }
@@ -87,6 +93,8 @@
       return this.getBaseUrl() + '/accounts/' +
         encodeURIComponent(this._getAccounts(account)) +
         '/avatar?s=' + this.imageSize;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrAvatar.is, GrAvatar);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_test.html b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_test.html
index 3456c13..98a75dd 100644
--- a/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-avatar/gr-avatar_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-avatar</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -49,28 +49,28 @@
     });
 
     test('methods', () => {
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             _account_id: 123,
           }),
           '/accounts/123/avatar?s=16');
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             email: 'test@example.com',
           }),
           '/accounts/test%40example.com/avatar?s=16');
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             name: 'John Doe',
           }),
           '/accounts/John%20Doe/avatar?s=16');
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             username: 'John_Doe',
           }),
           '/accounts/John_Doe/avatar?s=16');
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             _account_id: 123,
             avatars: [
               {
@@ -88,8 +88,8 @@
             ],
           }),
           'https://cdn.example.com/s16-p/photo.jpg');
-      assert.equal(element._buildAvatarURL(
-          {
+      assert.equal(
+          element._buildAvatarURL({
             _account_id: 123,
             avatars: [
               {
diff --git a/polygerrit-ui/app/elements/shared/gr-button/gr-button.js b/polygerrit-ui/app/elements/shared/gr-button/gr-button.js
index afc6ba8..8c9ba50 100644
--- a/polygerrit-ui/app/elements/shared/gr-button/gr-button.js
+++ b/polygerrit-ui/app/elements/shared/gr-button/gr-button.js
@@ -17,65 +17,77 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-button',
+  /**
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.TooltipMixin
+    */
+  class GrButton extends Polymer.mixinBehaviors( [
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-button'; }
 
-    properties: {
-      tooltip: String,
-      downArrow: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-      link: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      loading: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      disabled: {
-        type: Boolean,
-        observer: '_disabledChanged',
-        reflectToAttribute: true,
-      },
-      noUppercase: {
-        type: Boolean,
-        value: false,
-      },
-      _enabledTabindex: {
-        type: String,
-        value: '0',
-      },
-    },
+    static get properties() {
+      return {
+        tooltip: String,
+        downArrow: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+        link: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        loading: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        disabled: {
+          type: Boolean,
+          observer: '_disabledChanged',
+          reflectToAttribute: true,
+        },
+        noUppercase: {
+          type: Boolean,
+          value: false,
+        },
+        _enabledTabindex: {
+          type: String,
+          value: '0',
+        },
+      };
+    }
 
-    listeners: {
-      click: '_handleAction',
-      keydown: '_handleKeydown',
-    },
+    static get observers() {
+      return [
+        '_computeDisabled(disabled, loading)',
+      ];
+    }
 
-    observers: [
-      '_computeDisabled(disabled, loading)',
-    ],
+    created() {
+      super.created();
+      this.addEventListener('click',
+          e => this._handleAction(e));
+      this.addEventListener('keydown',
+          e => this._handleKeydown(e));
+    }
 
-    behaviors: [
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.TooltipBehavior,
-    ],
-
-    hostAttributes: {
-      role: 'button',
-      tabindex: '0',
-    },
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'button');
+      this._ensureAttribute('tabindex', '0');
+    }
 
     _handleAction(e) {
       if (this.disabled) {
         e.preventDefault();
         e.stopImmediatePropagation();
       }
-    },
+    }
 
     _disabledChanged(disabled) {
       if (disabled) {
@@ -83,11 +95,11 @@
       }
       this.setAttribute('tabindex', disabled ? '-1' : this._enabledTabindex);
       this.updateStyles();
-    },
+    }
 
     _computeDisabled(disabled, loading) {
       return disabled || loading;
-    },
+    }
 
     _handleKeydown(e) {
       if (this.modifierPressed(e)) { return; }
@@ -98,6 +110,8 @@
         e.stopPropagation();
         this.click();
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrButton.is, GrButton);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-button/gr-button_test.html b/polygerrit-ui/app/elements/shared/gr-button/gr-button_test.html
index ef593c0..bcb560a 100644
--- a/polygerrit-ui/app/elements/shared/gr-button/gr-button_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-button/gr-button_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-button</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star.js b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star.js
index a83bc2b..05e759f 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star.js
+++ b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star.js
@@ -17,31 +17,34 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-change-star',
-
+  class GrChangeStar extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-change-star'; }
     /**
      * Fired when star state is toggled.
      *
      * @event toggle-star
      */
 
-    properties: {
+    static get properties() {
+      return {
       /** @type {?} */
-      change: {
-        type: Object,
-        notify: true,
-      },
-    },
+        change: {
+          type: Object,
+          notify: true,
+        },
+      };
+    }
 
     _computeStarClass(starred) {
       return starred ? 'active' : '';
-    },
+    }
 
     _computeStarIcon(starred) {
       // Hollow star is used to indicate inactive state.
       return `gr-icons:star${starred ? '' : '-border'}`;
-    },
+    }
 
     toggleStar() {
       const newVal = !this.change.starred;
@@ -51,6 +54,8 @@
         composed: true,
         detail: {change: this.change, starred: newVal},
       }));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeStar.is, GrChangeStar);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_test.html b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_test.html
index 7ee22a7..60c504a 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-change-star/gr-change-star_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-star</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status.js b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status.js
index e6f52c6..35b8ef8 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status.js
+++ b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status.js
@@ -36,35 +36,39 @@
   const PRIVATE_TOOLTIP = 'This change is only visible to its owner and ' +
       'current reviewers (or anyone with "View Private Changes" permission).';
 
-  Polymer({
-    is: 'gr-change-status',
+  class GrChangeStatus extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-change-status'; }
 
-    properties: {
-      flat: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      status: {
-        type: String,
-        observer: '_updateChipDetails',
-      },
-      tooltipText: {
-        type: String,
-        value: '',
-      },
-    },
+    static get properties() {
+      return {
+        flat: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        status: {
+          type: String,
+          observer: '_updateChipDetails',
+        },
+        tooltipText: {
+          type: String,
+          value: '',
+        },
+      };
+    }
 
     _computeStatusString(status) {
       if (status === ChangeStates.WIP && !this.flat) {
         return 'Work in Progress';
       }
       return status;
-    },
+    }
 
     _toClassName(str) {
       return str.toLowerCase().replace(/\s/g, '-');
-    },
+    }
 
     _updateChipDetails(status, previousStatus) {
       if (previousStatus) {
@@ -86,6 +90,8 @@
           this.tooltipText = '';
           break;
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrChangeStatus.is, GrChangeStatus);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_test.html b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_test.html
index 421c6ab5..96a1840 100644
--- a/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-change-status/gr-change-status_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-status</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.html b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.html
index bbd7ddf..89b28d5 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.html
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.html
@@ -58,6 +58,9 @@
       #container.unresolved {
         background-color: var(--unresolved-comment-background-color);
       }
+      #container.robotComment {
+        background-color: var(--robot-comment-background-color);
+      }
       #commentInfoContainer {
         border-top: 1px dotted var(--border-color);
         display: flex;
@@ -82,19 +85,18 @@
         <span class="descriptionText">Patchset [[patchNum]]</span>
       </div>
     </template>
-    <div id="container" class$="[[_computeHostClass(unresolved)]]">
+    <div id="container" class$="[[_computeHostClass(unresolved, isRobotComment)]]">
       <template id="commentList" is="dom-repeat" items="[[_orderedComments]]"
           as="comment">
         <gr-comment
             comment="{{comment}}"
-            robot-button-disabled="[[_hideActions(_showActions, _lastComment)]]"
+            robot-button-disabled="[[_shouldDisableAction(_showActions, _lastComment)]]"
             change-num="[[changeNum]]"
             patch-num="[[patchNum]]"
             draft="[[_isDraft(comment)]]"
             show-actions="[[_showActions]]"
             comment-side="[[comment.__commentSide]]"
             side="[[comment.side]]"
-            root-id="[[rootId]]"
             project-config="[[_projectConfig]]"
             on-create-fix-comment="_handleCommentFix"
             on-comment-discard="_handleCommentDiscard"
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.js b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.js
index b7fe8b0..8687e77 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.js
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.js
@@ -20,9 +20,22 @@
   const UNRESOLVED_EXPAND_COUNT = 5;
   const NEWLINE_PATTERN = /\n/g;
 
-  Polymer({
-    is: 'gr-comment-thread',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    * @appliesMixin Gerrit.PathListMixin
+    */
+  class GrCommentThread extends Polymer.mixinBehaviors( [
+    /**
+       * Not used in this element rather other elements tests
+       */
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+    Gerrit.PathListBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-comment-thread'; }
     /**
      * Fired when the thread should be discarded.
      *
@@ -35,123 +48,128 @@
      * @event thread-changed
      */
 
-     /**
-      * gr-comment-thread exposes the following attributes that allow a
-      * diff widget like gr-diff to show the thread in the right location:
-      *
-      * line-num:
-      *     1-based line number or undefined if it refers to the entire file.
-      *
-      * comment-side:
-      *     "left" or "right". These indicate which of the two diffed versions
-      *     the comment relates to. In the case of unified diff, the left
-      *     version is the one whose line number column is further to the left.
-      *
-      * range:
-      *     The range of text that the comment refers to (start_line,
-      *     start_character, end_line, end_character), serialized as JSON. If
-      *     set, range's end_line will have the same value as line-num. Line
-      *     numbers are 1-based, char numbers are 0-based. The start position
-      *     (start_line, start_character) is inclusive, and the end position
-      *     (end_line, end_character) is exclusive.
-      */
-    properties: {
-      changeNum: String,
-      comments: {
-        type: Array,
-        value() { return []; },
-      },
-      /**
+    /**
+              * gr-comment-thread exposes the following attributes that allow a
+              * diff widget like gr-diff to show the thread in the right location:
+              *
+              * line-num:
+              *     1-based line number or undefined if it refers to the entire file.
+              *
+              * comment-side:
+              *     "left" or "right". These indicate which of the two diffed versions
+              *     the comment relates to. In the case of unified diff, the left
+              *     version is the one whose line number column is further to the left.
+              *
+              * range:
+              *     The range of text that the comment refers to (start_line,
+              *     start_character, end_line, end_character), serialized as JSON. If
+              *     set, range's end_line will have the same value as line-num. Line
+              *     numbers are 1-based, char numbers are 0-based. The start position
+              *     (start_line, start_character) is inclusive, and the end position
+              *     (end_line, end_character) is exclusive.
+              */
+    static get properties() {
+      return {
+        changeNum: String,
+        comments: {
+          type: Array,
+          value() { return []; },
+        },
+        /**
        * @type {?{start_line: number, start_character: number, end_line: number,
        *          end_character: number}}
        */
-      range: {
-        type: Object,
-        reflectToAttribute: true,
-      },
-      keyEventTarget: {
-        type: Object,
-        value() { return document.body; },
-      },
-      commentSide: {
-        type: String,
-        reflectToAttribute: true,
-      },
-      patchNum: String,
-      path: String,
-      projectName: {
-        type: String,
-        observer: '_projectNameChanged',
-      },
-      hasDraft: {
-        type: Boolean,
-        notify: true,
-        reflectToAttribute: true,
-      },
-      isOnParent: {
-        type: Boolean,
-        value: false,
-      },
-      parentIndex: {
-        type: Number,
-        value: null,
-      },
-      rootId: {
-        type: String,
-        notify: true,
-        computed: '_computeRootId(comments.*)',
-      },
-      /**
+        range: {
+          type: Object,
+          reflectToAttribute: true,
+        },
+        keyEventTarget: {
+          type: Object,
+          value() { return document.body; },
+        },
+        commentSide: {
+          type: String,
+          reflectToAttribute: true,
+        },
+        patchNum: String,
+        path: String,
+        projectName: {
+          type: String,
+          observer: '_projectNameChanged',
+        },
+        hasDraft: {
+          type: Boolean,
+          notify: true,
+          reflectToAttribute: true,
+        },
+        isOnParent: {
+          type: Boolean,
+          value: false,
+        },
+        parentIndex: {
+          type: Number,
+          value: null,
+        },
+        rootId: {
+          type: String,
+          notify: true,
+          computed: '_computeRootId(comments.*)',
+        },
+        /**
        * If this is true, the comment thread also needs to have the change and
        * line properties property set
        */
-      showFilePath: {
-        type: Boolean,
-        value: false,
-      },
-      /** Necessary only if showFilePath is true or when used with gr-diff */
-      lineNum: {
-        type: Number,
-        reflectToAttribute: true,
-      },
-      unresolved: {
-        type: Boolean,
-        notify: true,
-        reflectToAttribute: true,
-      },
-      _showActions: Boolean,
-      _lastComment: Object,
-      _orderedComments: Array,
-      _projectConfig: Object,
-    },
+        showFilePath: {
+          type: Boolean,
+          value: false,
+        },
+        /** Necessary only if showFilePath is true or when used with gr-diff */
+        lineNum: {
+          type: Number,
+          reflectToAttribute: true,
+        },
+        unresolved: {
+          type: Boolean,
+          notify: true,
+          reflectToAttribute: true,
+        },
+        _showActions: Boolean,
+        _lastComment: Object,
+        _orderedComments: Array,
+        _projectConfig: Object,
+        isRobotComment: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+      };
+    }
 
-    behaviors: [
-      /**
-       * Not used in this element rather other elements tests
-       */
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-      Gerrit.PathListBehavior,
-    ],
+    static get observers() {
+      return [
+        '_commentsChanged(comments.*)',
+      ];
+    }
 
-    listeners: {
-      'comment-update': '_handleCommentUpdate',
-    },
+    get keyBindings() {
+      return {
+        'e shift+e': '_handleEKey',
+      };
+    }
 
-    observers: [
-      '_commentsChanged(comments.*)',
-    ],
-
-    keyBindings: {
-      'e shift+e': '_handleEKey',
-    },
+    created() {
+      super.created();
+      this.addEventListener('comment-update',
+          e => this._handleCommentUpdate(e));
+    }
 
     attached() {
+      super.attached();
       this._getLoggedIn().then(loggedIn => {
         this._showActions = loggedIn;
       });
       this._setInitialExpandedState();
-    },
+    }
 
     addOrEditDraft(opt_lineNum, opt_range) {
       const lastComment = this.comments[this.comments.length - 1] || {};
@@ -165,60 +183,65 @@
         commentEl.collapsed = false;
       } else {
         const range = opt_range ? opt_range :
-            lastComment ? lastComment.range : undefined;
+          lastComment ? lastComment.range : undefined;
         const unresolved = lastComment ? lastComment.unresolved : undefined;
         this.addDraft(opt_lineNum, range, unresolved);
       }
-    },
+    }
 
     addDraft(opt_lineNum, opt_range, opt_unresolved) {
       const draft = this._newDraft(opt_lineNum, opt_range);
       draft.__editing = true;
       draft.unresolved = opt_unresolved === false ? opt_unresolved : true;
       this.push('comments', draft);
-    },
+    }
 
     fireRemoveSelf() {
       this.dispatchEvent(new CustomEvent('thread-discard',
           {detail: {rootId: this.rootId}, bubbles: false}));
-    },
+    }
 
     _getDiffUrlForComment(projectName, changeNum, path, patchNum) {
       return Gerrit.Nav.getUrlForDiffById(changeNum,
           projectName, path, patchNum,
           null, this.lineNum);
-    },
+    }
 
     _computeDisplayPath(path) {
       const lineString = this.lineNum ? `#${this.lineNum}` : '';
       return this.computeDisplayPath(path) + lineString;
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _commentsChanged() {
       this._orderedComments = this._sortedComments(this.comments);
       this.updateThreadProperties();
-    },
+    }
 
     updateThreadProperties() {
       if (this._orderedComments.length) {
         this._lastComment = this._getLastComment();
         this.unresolved = this._lastComment.unresolved;
         this.hasDraft = this._lastComment.__draft;
+        this.isRobotComment = !!(this._lastComment.robot_id);
       }
-    },
+    }
+
+    _shouldDisableAction(_showActions, _lastComment) {
+      return !_showActions || !_lastComment || !!_lastComment.__draft;
+    }
 
     _hideActions(_showActions, _lastComment) {
-      return !_showActions || !_lastComment || !!_lastComment.__draft ||
+      return this._shouldDisableAction(_showActions, _lastComment) ||
         !!_lastComment.robot_id;
-    },
+    }
 
     _getLastComment() {
       return this._orderedComments[this._orderedComments.length - 1] || {};
-    },
+    }
 
     _handleEKey(e) {
       if (this.shouldSuppressKeyboardShortcut(e)) { return; }
@@ -231,7 +254,7 @@
         if (this.modifierPressed(e)) { return; }
         this._expandCollapseComments(false);
       }
-    },
+    }
 
     _expandCollapseComments(actionIsCollapse) {
       const comments =
@@ -239,7 +262,7 @@
       for (const comment of comments) {
         comment.collapsed = actionIsCollapse;
       }
-    },
+    }
 
     /**
      * Sets the initial state of the comment thread.
@@ -259,7 +282,7 @@
           comment.collapsed = !isRobotComment && resolvedThread;
         }
       }
-    },
+    }
 
     _sortedComments(comments) {
       return comments.slice().sort((c1, c2) => {
@@ -275,7 +298,7 @@
         // If same date, fall back to sorting by id.
         return dateCompare ? dateCompare : c1.id.localeCompare(c2.id);
       });
-    },
+    }
 
     _createReplyComment(parent, content, opt_isEditing,
         opt_unresolved) {
@@ -309,11 +332,11 @@
           commentEl.save();
         }, 1);
       }
-    },
+    }
 
     _isDraft(comment) {
       return !!comment.__draft;
-    },
+    }
 
     /**
      * @param {boolean=} opt_quote
@@ -326,25 +349,25 @@
         quoteStr = '> ' + msg.replace(NEWLINE_PATTERN, '\n> ') + '\n\n';
       }
       this._createReplyComment(comment, quoteStr, true, comment.unresolved);
-    },
+    }
 
     _handleCommentReply(e) {
       this._processCommentReply();
-    },
+    }
 
     _handleCommentQuote(e) {
       this._processCommentReply(true);
-    },
+    }
 
     _handleCommentAck(e) {
       const comment = this._lastComment;
       this._createReplyComment(comment, 'Ack', false, false);
-    },
+    }
 
     _handleCommentDone(e) {
       const comment = this._lastComment;
       this._createReplyComment(comment, 'Done', false, false);
-    },
+    }
 
     _handleCommentFix(e) {
       const comment = e.detail.comment;
@@ -352,7 +375,7 @@
       const quoteStr = '> ' + msg.replace(NEWLINE_PATTERN, '\n> ') + '\n\n';
       const response = quoteStr + 'Please Fix';
       this._createReplyComment(comment, response, false, true);
-    },
+    }
 
     _commentElWithDraftID(id) {
       const els = Polymer.dom(this.root).querySelectorAll('gr-comment');
@@ -362,7 +385,7 @@
         }
       }
       return null;
-    },
+    }
 
     _newReply(inReplyTo, opt_lineNum, opt_message, opt_unresolved,
         opt_range) {
@@ -376,7 +399,7 @@
         d.unresolved = opt_unresolved;
       }
       return d;
-    },
+    }
 
     /**
      * @param {number=} opt_lineNum
@@ -402,12 +425,12 @@
         d.parent = this.parentIndex;
       }
       return d;
-    },
+    }
 
     _getSide(isOnParent) {
       if (isOnParent) { return 'PARENT'; }
       return 'REVISION';
-    },
+    }
 
     _computeRootId(comments) {
       // Keep the root ID even if the comment was removed, so that notification
@@ -415,7 +438,7 @@
       if (!comments.base.length) { return this.rootId; }
       const rootComment = comments.base[0];
       return rootComment.id || rootComment.__draftID;
-    },
+    }
 
     _handleCommentDiscard(e) {
       const diffCommentEl = Polymer.dom(e).rootTarget;
@@ -445,13 +468,13 @@
               changeComment.message);
         }
       }
-    },
+    }
 
     _handleCommentSavedOrDiscarded(e) {
       this.dispatchEvent(new CustomEvent('thread-changed',
           {detail: {rootId: this.rootId, path: this.path},
             bubbles: false}));
-    },
+    }
 
     _handleCommentUpdate(e) {
       const comment = e.detail.comment;
@@ -467,7 +490,7 @@
       // observers, the this.set() call above will not cause a thread update in
       // some situations.
       this.updateThreadProperties();
-    },
+    }
 
     _indexOf(comment, arr) {
       for (let i = 0; i < arr.length; i++) {
@@ -478,11 +501,14 @@
         }
       }
       return -1;
-    },
+    }
 
     _computeHostClass(unresolved) {
+      if (this.isRobotComment) {
+        return 'robotComment';
+      }
       return unresolved ? 'unresolved' : '';
-    },
+    }
 
     /**
      * Load the project config when a project name has been provided.
@@ -493,6 +519,8 @@
       this.$.restAPI.getProjectConfig(name).then(config => {
         this._projectConfig = config;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCommentThread.is, GrCommentThread);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_test.html b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_test.html
index b6222b4..17e0b1f 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-comment-thread</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -152,6 +152,24 @@
       assert.isTrue(addDraftStub.called);
     });
 
+    test('_shouldDisableAction', () => {
+      let showActions = true;
+      const lastComment = {};
+      assert.equal(
+          element._shouldDisableAction(showActions, lastComment), false);
+      showActions = false;
+      assert.equal(
+          element._shouldDisableAction(showActions, lastComment), true);
+      showActions = true;
+      lastComment.__draft = true;
+      assert.equal(
+          element._shouldDisableAction(showActions, lastComment), true);
+      const robotComment = {};
+      robotComment.robot_id = true;
+      assert.equal(
+          element._shouldDisableAction(showActions, robotComment), false);
+    });
+
     test('_hideActions', () => {
       let showActions = true;
       const lastComment = {};
@@ -469,7 +487,7 @@
             done();
           });
           draftEl.fire('comment-discard', {comment: draftEl.comment},
-          {bubbles: false});
+              {bubbles: false});
         });
 
     test('first editing comment does not add __otherEditing attribute', () => {
diff --git a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.html b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.html
index 8ad261c..46fa3cf 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.html
+++ b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.html
@@ -305,7 +305,6 @@
         <gr-formatted-text class="message"
             content="[[comment.message]]"
             no-trailing-margin="[[!comment.__draft]]"
-            collapsed="[[collapsed]]"
             config="[[projectConfig.commentlinks]]"></gr-formatted-text>
         <div hidden$="[[!comment.robot_run_id]]" class="message">
           <div class="runIdInformation" hidden$="[[collapsed]]">
diff --git a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.js b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.js
index d41ef7f..dd2855c 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.js
+++ b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment.js
@@ -31,9 +31,17 @@
 
   const FILE = 'FILE';
 
-  Polymer({
-    is: 'gr-comment',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrComment extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-comment'; }
     /**
      * Fired when the create fix comment action is triggered.
      *
@@ -64,108 +72,111 @@
      * @event comment-anchor-tap
      */
 
-    properties: {
-      changeNum: String,
-      /** @type {?} */
-      comment: {
-        type: Object,
-        notify: true,
-        observer: '_commentChanged',
-      },
-      isRobotComment: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      draft: {
-        type: Boolean,
-        value: false,
-        observer: '_draftChanged',
-      },
-      editing: {
-        type: Boolean,
-        value: false,
-        observer: '_editingChanged',
-      },
-      discarding: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      hasChildren: Boolean,
-      patchNum: String,
-      showActions: Boolean,
-      _showHumanActions: Boolean,
-      _showRobotActions: Boolean,
-      collapsed: {
-        type: Boolean,
-        value: true,
-        observer: '_toggleCollapseClass',
-      },
-      /** @type {?} */
-      projectConfig: Object,
-      robotButtonDisabled: Boolean,
-      _isAdmin: {
-        type: Boolean,
-        value: false,
-      },
+    static get properties() {
+      return {
+        changeNum: String,
+        /** @type {?} */
+        comment: {
+          type: Object,
+          notify: true,
+          observer: '_commentChanged',
+        },
+        isRobotComment: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        draft: {
+          type: Boolean,
+          value: false,
+          observer: '_draftChanged',
+        },
+        editing: {
+          type: Boolean,
+          value: false,
+          observer: '_editingChanged',
+        },
+        discarding: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        hasChildren: Boolean,
+        patchNum: String,
+        showActions: Boolean,
+        _showHumanActions: Boolean,
+        _showRobotActions: Boolean,
+        collapsed: {
+          type: Boolean,
+          value: true,
+          observer: '_toggleCollapseClass',
+        },
+        /** @type {?} */
+        projectConfig: Object,
+        robotButtonDisabled: Boolean,
+        _isAdmin: {
+          type: Boolean,
+          value: false,
+        },
 
-      _xhrPromise: Object, // Used for testing.
-      _messageText: {
-        type: String,
-        value: '',
-        observer: '_messageTextChanged',
-      },
-      commentSide: String,
+        _xhrPromise: Object, // Used for testing.
+        _messageText: {
+          type: String,
+          value: '',
+          observer: '_messageTextChanged',
+        },
+        commentSide: String,
+        side: String,
 
-      resolved: Boolean,
+        resolved: Boolean,
 
-      _numPendingDraftRequests: {
-        type: Object,
-        value:
+        _numPendingDraftRequests: {
+          type: Object,
+          value:
             {number: 0}, // Intentional to share the object across instances.
-      },
+        },
 
-      _enableOverlay: {
-        type: Boolean,
-        value: false,
-      },
+        _enableOverlay: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * Property for storing references to overlay elements. When the overlays
        * are moved to Gerrit.getRootElement() to be shown they are no-longer
        * children, so they can't be queried along the tree, so they are stored
        * here.
        */
-      _overlays: {
-        type: Object,
-        value: () => ({}),
-      },
-    },
+        _overlays: {
+          type: Object,
+          value: () => ({}),
+        },
+      };
+    }
 
-    observers: [
-      '_commentMessageChanged(comment.message)',
-      '_loadLocalDraft(changeNum, patchNum, comment)',
-      '_isRobotComment(comment)',
-      '_calculateActionstoShow(showActions, isRobotComment)',
-    ],
+    static get observers() {
+      return [
+        '_commentMessageChanged(comment.message)',
+        '_loadLocalDraft(changeNum, patchNum, comment)',
+        '_isRobotComment(comment)',
+        '_calculateActionstoShow(showActions, isRobotComment)',
+      ];
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    keyBindings: {
-      'ctrl+enter meta+enter ctrl+s meta+s': '_handleSaveKey',
-      'esc': '_handleEsc',
-    },
+    get keyBindings() {
+      return {
+        'ctrl+enter meta+enter ctrl+s meta+s': '_handleSaveKey',
+        'esc': '_handleEsc',
+      };
+    }
 
     attached() {
+      super.attached();
       if (this.editing) {
         this.collapsed = false;
       } else if (this.comment) {
@@ -174,18 +185,19 @@
       this._getIsAdmin().then(isAdmin => {
         this._isAdmin = isAdmin;
       });
-    },
+    }
 
     detached() {
+      super.detached();
       this.cancelDebouncer('fire-update');
       if (this.textarea) {
         this.textarea.closeDropdown();
       }
-    },
+    }
 
     get textarea() {
       return this.$$('#editTextarea');
-    },
+    }
 
     get confirmDeleteOverlay() {
       if (!this._overlays.confirmDelete) {
@@ -194,7 +206,7 @@
         this._overlays.confirmDelete = this.$$('#confirmDeleteOverlay');
       }
       return this._overlays.confirmDelete;
-    },
+    }
 
     get confirmDiscardOverlay() {
       if (!this._overlays.confirmDiscard) {
@@ -203,11 +215,11 @@
         this._overlays.confirmDiscard = this.$$('#confirmDiscardOverlay');
       }
       return this._overlays.confirmDiscard;
-    },
+    }
 
     _computeShowHideIcon(collapsed) {
       return collapsed ? 'gr-icons:expand-more' : 'gr-icons:expand-less';
-    },
+    }
 
     _calculateActionstoShow(showActions, isRobotComment) {
       // Polymer 2: check for undefined
@@ -217,19 +229,19 @@
 
       this._showHumanActions = showActions && !isRobotComment;
       this._showRobotActions = showActions && isRobotComment;
-    },
+    }
 
     _isRobotComment(comment) {
       this.isRobotComment = !!comment.robot_id;
-    },
+    }
 
     isOnParent() {
       return this.side === 'PARENT';
-    },
+    }
 
     _getIsAdmin() {
       return this.$.restAPI.getIsAdmin();
-    },
+    }
 
     /**
      * @param {*=} opt_comment
@@ -272,7 +284,7 @@
       });
 
       return this._xhrPromise;
-    },
+    }
 
     _eraseDraftComment() {
       // Prevents a race condition in which removing the draft comment occurs
@@ -286,7 +298,7 @@
         line: this.comment.line,
         range: this.comment.range,
       });
-    },
+    }
 
     _commentChanged(comment) {
       this.editing = !!comment.__editing;
@@ -294,7 +306,7 @@
       if (this.editing) { // It's a new draft/reply, notify.
         this._fireUpdate();
       }
-    },
+    }
 
     /**
      * @param {!Object=} opt_mixin
@@ -306,21 +318,21 @@
         comment: this.comment,
         patchNum: this.patchNum,
       });
-    },
+    }
 
     _fireSave() {
       this.fire('comment-save', this._getEventPayload());
-    },
+    }
 
     _fireUpdate() {
       this.debounce('fire-update', () => {
         this.fire('comment-update', this._getEventPayload());
       });
-    },
+    }
 
     _draftChanged(draft) {
       this.$.container.classList.toggle('draft', draft);
-    },
+    }
 
     _editingChanged(editing, previousValue) {
       // Polymer 2: observer fires when at least one property is defined.
@@ -345,11 +357,11 @@
           this.textarea.putCursorAtEnd();
         }, 1);
       }
-    },
+    }
 
     _computeDeleteButtonClass(isAdmin, draft) {
       return isAdmin && !draft ? 'showDeleteButtons' : '';
-    },
+    }
 
     _computeSaveDisabled(draft, comment, resolved) {
       // If resolved state has changed and a msg exists, save should be enabled.
@@ -357,7 +369,7 @@
         return false;
       }
       return !draft || draft.trim() === '';
-    },
+    }
 
     _handleSaveKey(e) {
       if (!this._computeSaveDisabled(this._messageText, this.comment,
@@ -365,18 +377,18 @@
         e.preventDefault();
         this._handleSave(e);
       }
-    },
+    }
 
     _handleEsc(e) {
       if (!this._messageText.length) {
         e.preventDefault();
         this._handleCancel(e);
       }
-    },
+    }
 
     _handleToggleCollapsed() {
       this.collapsed = !this.collapsed;
-    },
+    }
 
     _toggleCollapseClass(collapsed) {
       if (collapsed) {
@@ -384,11 +396,11 @@
       } else {
         this.$.container.classList.remove('collapsed');
       }
-    },
+    }
 
     _commentMessageChanged(message) {
       this._messageText = message || '';
-    },
+    }
 
     _messageTextChanged(newValue, oldValue) {
       if (!this.comment || (this.comment && this.comment.id)) {
@@ -413,7 +425,7 @@
           this.$.storage.setDraftComment(commentLocation, message);
         }
       }, STORAGE_DEBOUNCE_INTERVAL);
-    },
+    }
 
     _handleAnchorClick(e) {
       e.preventDefault();
@@ -428,14 +440,14 @@
           side: this.side,
         },
       }));
-    },
+    }
 
     _handleEdit(e) {
       e.preventDefault();
       this._messageText = this.comment.message;
       this.editing = true;
       this.$.reporting.recordDraftInteraction();
-    },
+    }
 
     _handleSave(e) {
       e.preventDefault();
@@ -445,11 +457,11 @@
         return;
       }
       const timingLabel = this.comment.id ?
-          REPORT_UPDATE_DRAFT : REPORT_CREATE_DRAFT;
+        REPORT_UPDATE_DRAFT : REPORT_CREATE_DRAFT;
       const timer = this.$.reporting.getTimer(timingLabel);
       this.set('comment.__editing', false);
       return this.save().then(() => { timer.end(); });
-    },
+    }
 
     _handleCancel(e) {
       e.preventDefault();
@@ -462,12 +474,12 @@
       }
       this._messageText = this.comment.message;
       this.editing = false;
-    },
+    }
 
     _fireDiscard() {
       this.cancelDebouncer('fire-update');
       this.fire('comment-discard', this._getEventPayload());
-    },
+    }
 
     _handleFix() {
       this.dispatchEvent(new CustomEvent('create-fix-comment', {
@@ -475,7 +487,7 @@
         composed: true,
         detail: this._getEventPayload(),
       }));
-    },
+    }
 
     _handleDiscard(e) {
       e.preventDefault();
@@ -490,14 +502,14 @@
         this.confirmDiscardOverlay.querySelector('#confirmDiscardDialog')
             .resetFocus();
       });
-    },
+    }
 
     _handleConfirmDiscard(e) {
       e.preventDefault();
       const timer = this.$.reporting.getTimer(REPORT_DISCARD_DRAFT);
       this._closeConfirmDiscardOverlay();
       return this._discardDraft().then(() => { timer.end(); });
-    },
+    }
 
     _discardDraft() {
       if (!this.comment.__draft) {
@@ -528,11 +540,11 @@
       });
 
       return this._xhrPromise;
-    },
+    }
 
     _closeConfirmDiscardOverlay() {
       this._closeOverlay(this.confirmDiscardOverlay);
-    },
+    }
 
     _getSavingMessage(numPending) {
       if (numPending === 0) {
@@ -543,17 +555,17 @@
         numPending,
         numPending === 1 ? DRAFT_SINGULAR : DRAFT_PLURAL,
       ].join(' ');
-    },
+    }
 
     _showStartRequest() {
       const numPending = ++this._numPendingDraftRequests.number;
       this._updateRequestToast(numPending);
-    },
+    }
 
     _showEndRequest() {
       const numPending = --this._numPendingDraftRequests.number;
       this._updateRequestToast(numPending);
-    },
+    }
 
     _handleFailedDraftRequest() {
       this._numPendingDraftRequests.number--;
@@ -561,7 +573,7 @@
       // Cancel the debouncer so that error toasts from the error-manager will
       // not be overridden.
       this.cancelDebouncer('draft-toast');
-    },
+    }
 
     _updateRequestToast(numPending) {
       const message = this._getSavingMessage(numPending);
@@ -572,7 +584,7 @@
         document.body.dispatchEvent(new CustomEvent(
             'show-alert', {detail: {message}, bubbles: true, composed: true}));
       }, TOAST_DEBOUNCE_INTERVAL);
-    },
+    }
 
     _saveDraft(draft) {
       this._showStartRequest();
@@ -585,24 +597,24 @@
             }
             return result;
           });
-    },
+    }
 
     _deleteDraft(draft) {
       this._showStartRequest();
       return this.$.restAPI.deleteDiffDraft(this.changeNum, this.patchNum,
           draft).then(result => {
-            if (result.ok) {
-              this._showEndRequest();
-            } else {
-              this._handleFailedDraftRequest();
-            }
-            return result;
-          });
-    },
+        if (result.ok) {
+          this._showEndRequest();
+        } else {
+          this._handleFailedDraftRequest();
+        }
+        return result;
+      });
+    }
 
     _getPatchNum() {
       return this.isOnParent() ? 'PARENT' : this.patchNum;
-    },
+    }
 
     _loadLocalDraft(changeNum, patchNum, comment) {
       // Polymer 2: check for undefined
@@ -631,7 +643,7 @@
       if (draft) {
         this.set('comment.message', draft.message);
       }
-    },
+    }
 
     _handleToggleResolved() {
       this.$.reporting.recordDraftInteraction();
@@ -645,25 +657,25 @@
         // Save the resolved state immediately.
         this.save(payload.comment);
       }
-    },
+    }
 
     _handleCommentDelete() {
       this._openOverlay(this.confirmDeleteOverlay);
-    },
+    }
 
     _handleCancelDeleteComment() {
       this._closeOverlay(this.confirmDeleteOverlay);
-    },
+    }
 
     _openOverlay(overlay) {
       Polymer.dom(Gerrit.getRootElement()).appendChild(overlay);
       return overlay.open();
-    },
+    }
 
     _closeOverlay(overlay) {
       Polymer.dom(Gerrit.getRootElement()).removeChild(overlay);
       overlay.close();
-    },
+    }
 
     _handleConfirmDeleteComment() {
       const dialog =
@@ -674,6 +686,8 @@
             this._handleCancelDeleteComment();
             this.comment = newComment;
           });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrComment.is, GrComment);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_test.html b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_test.html
index c829343..de75b40 100644
--- a/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-comment/gr-comment_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-comment</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -44,7 +44,6 @@
 </test-fixture>
 
 <script>
-
   function isVisible(el) {
     assert.ok(el);
     return getComputedStyle(el).getPropertyValue('display') !== 'none';
diff --git a/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog.js b/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog.js
index c2075f0..79cd251 100644
--- a/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog.js
+++ b/polygerrit-ui/app/elements/shared/gr-confirm-delete-comment-dialog/gr-confirm-delete-comment-dialog.js
@@ -17,9 +17,15 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-confirm-delete-comment-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrConfirmDeleteCommentDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-confirm-delete-comment-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -32,28 +38,29 @@
      * @event cancel
      */
 
-    properties: {
-      message: String,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        message: String,
+      };
+    }
 
     resetFocus() {
       this.$.messageInput.textarea.focus();
-    },
+    }
 
     _handleConfirmTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', {reason: this.message}, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
-  });
+    }
+  }
+
+  customElements.define(GrConfirmDeleteCommentDialog.is,
+      GrConfirmDeleteCommentDialog);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard.js b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard.js
index 3e87202..6c062f6 100644
--- a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard.js
+++ b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard.js
@@ -19,34 +19,38 @@
 
   const COPY_TIMEOUT_MS = 1000;
 
-  Polymer({
-    is: 'gr-copy-clipboard',
+  class GrCopyClipboard extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-copy-clipboard'; }
 
-    properties: {
-      text: String,
-      buttonTitle: String,
-      hasTooltip: {
-        type: Boolean,
-        value: false,
-      },
-      hideInput: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        text: String,
+        buttonTitle: String,
+        hasTooltip: {
+          type: Boolean,
+          value: false,
+        },
+        hideInput: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     focusOnCopy() {
       this.$.button.focus();
-    },
+    }
 
     _computeInputClass(hideInput) {
       return hideInput ? 'hideInput' : '';
-    },
+    }
 
     _handleInputClick(e) {
       e.preventDefault();
       Polymer.dom(e).rootTarget.select();
-    },
+    }
 
     _copyToClipboard() {
       if (this.hideInput) {
@@ -62,6 +66,8 @@
       this.async(
           () => this.$.icon.icon = 'gr-icons:content-copy',
           COPY_TIMEOUT_MS);
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCopyClipboard.is, GrCopyClipboard);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_test.html b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_test.html
index 9cec20e..14490f0 100644
--- a/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-copy-clipboard/gr-copy-clipboard_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-copy-clipboard</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-count-string-formatter/gr-count-string-formatter_test.html b/polygerrit-ui/app/elements/shared/gr-count-string-formatter/gr-count-string-formatter_test.html
index d061ac2..5022766 100644
--- a/polygerrit-ui/app/elements/shared/gr-count-string-formatter/gr-count-string-formatter_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-count-string-formatter/gr-count-string-formatter_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-count-string-formatter</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager.js b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager.js
index be40ce6..4232ef9 100644
--- a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager.js
+++ b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager.js
@@ -22,72 +22,77 @@
     KEEP_VISIBLE: 'keep-visible',
   };
 
-  Polymer({
-    is: 'gr-cursor-manager',
+  class GrCursorManager extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-cursor-manager'; }
 
-    properties: {
-      stops: {
-        type: Array,
-        value() {
-          return [];
+    static get properties() {
+      return {
+        stops: {
+          type: Array,
+          value() {
+            return [];
+          },
+          observer: '_updateIndex',
         },
-        observer: '_updateIndex',
-      },
-      /**
+        /**
        * @type (?Object)
        */
-      target: {
-        type: Object,
-        notify: true,
-        observer: '_scrollToTarget',
-      },
-      /**
+        target: {
+          type: Object,
+          notify: true,
+          observer: '_scrollToTarget',
+        },
+        /**
        * The height of content intended to be included with the target.
        * @type (?number)
        */
-      _targetHeight: Number,
+        _targetHeight: Number,
 
-      /**
+        /**
        * The index of the current target (if any). -1 otherwise.
        */
-      index: {
-        type: Number,
-        value: -1,
-        notify: true,
-      },
+        index: {
+          type: Number,
+          value: -1,
+          notify: true,
+        },
 
-      /**
+        /**
        * The class to apply to the current target. Use null for no class.
        */
-      cursorTargetClass: {
-        type: String,
-        value: null,
-      },
+        cursorTargetClass: {
+          type: String,
+          value: null,
+        },
 
-      /**
+        /**
        * The scroll behavior for the cursor. Values are 'never' and
        * 'keep-visible'. 'keep-visible' will only scroll if the cursor is beyond
        * the viewport.
        * TODO (beckysiegel) figure out why it can be undefined
        * @type (string|undefined)
        */
-      scrollBehavior: {
-        type: String,
-        value: ScrollBehavior.NEVER,
-      },
+        scrollBehavior: {
+          type: String,
+          value: ScrollBehavior.NEVER,
+        },
 
-      /**
+        /**
        * When true, will call element.focus() during scrolling.
        */
-      focusOnMove: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        focusOnMove: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     detached() {
+      super.detached();
       this.unsetCursor();
-    },
+    }
 
     /**
      * Move the cursor forward. Clipped to the ends of the stop list.
@@ -104,11 +109,11 @@
 
     next(opt_condition, opt_getTargetHeight, opt_clipToTop) {
       this._moveCursor(1, opt_condition, opt_getTargetHeight, opt_clipToTop);
-    },
+    }
 
     previous(opt_condition) {
       this._moveCursor(-1, opt_condition);
-    },
+    }
 
     /**
      * Set the cursor to an arbitrary element.
@@ -129,32 +134,32 @@
       this._decorateTarget();
 
       if (opt_noScroll) { this.scrollBehavior = behavior; }
-    },
+    }
 
     unsetCursor() {
       this._unDecorateTarget();
       this.index = -1;
       this.target = null;
       this._targetHeight = null;
-    },
+    }
 
     isAtStart() {
       return this.index === 0;
-    },
+    }
 
     isAtEnd() {
       return this.index === this.stops.length - 1;
-    },
+    }
 
     moveToStart() {
       if (this.stops.length) {
         this.setCursor(this.stops[0]);
       }
-    },
+    }
 
     setCursorAtIndex(index, opt_noScroll) {
       this.setCursor(this.stops[index], opt_noScroll);
-    },
+    }
 
     /**
      * Move the cursor forward or backward by delta. Clipped to the beginning or
@@ -199,19 +204,19 @@
       if (this.focusOnMove) { this.target.focus(); }
 
       this._decorateTarget();
-    },
+    }
 
     _decorateTarget() {
       if (this.target && this.cursorTargetClass) {
         this.target.classList.add(this.cursorTargetClass);
       }
-    },
+    }
 
     _unDecorateTarget() {
       if (this.target && this.cursorTargetClass) {
         this.target.classList.remove(this.cursorTargetClass);
       }
-    },
+    }
 
     /**
      * Get the next stop index indicated by the delta direction.
@@ -247,7 +252,7 @@
       }
 
       return newIndex;
-    },
+    }
 
     _updateIndex() {
       if (!this.target) {
@@ -261,7 +266,7 @@
       } else {
         this.index = newIndex;
       }
-    },
+    }
 
     /**
      * Calculate where the element is relative to the window.
@@ -271,12 +276,12 @@
     _getTop(target) {
       let top = target.offsetTop;
       for (let offsetParent = target.offsetParent;
-           offsetParent;
-           offsetParent = offsetParent.offsetParent) {
+        offsetParent;
+        offsetParent = offsetParent.offsetParent) {
         top += offsetParent.offsetTop;
       }
       return top;
-    },
+    }
 
     /**
      * @return {boolean}
@@ -286,12 +291,12 @@
       return this.scrollBehavior === ScrollBehavior.KEEP_VISIBLE &&
           top > dims.pageYOffset &&
           top < dims.pageYOffset + dims.innerHeight;
-    },
+    }
 
     _calculateScrollToValue(top, target) {
       const dims = this._getWindowDims();
       return top - (dims.innerHeight / 3) + (target.offsetHeight / 2);
-    },
+    }
 
     _scrollToTarget() {
       if (!this.target || this.scrollBehavior === ScrollBehavior.NEVER) {
@@ -301,7 +306,7 @@
       const dims = this._getWindowDims();
       const top = this._getTop(this.target);
       const bottomIsVisible = this._targetHeight ?
-          this._targetIsVisible(top + this._targetHeight) : true;
+        this._targetIsVisible(top + this._targetHeight) : true;
       const scrollToValue = this._calculateScrollToValue(top, this.target);
 
       if (this._targetIsVisible(top)) {
@@ -319,7 +324,7 @@
       // element appears to be below the center of the window even when it
       // isn't.
       window.scrollTo(dims.scrollX, scrollToValue);
-    },
+    }
 
     _getWindowDims() {
       return {
@@ -328,6 +333,8 @@
         innerHeight: window.innerHeight,
         pageYOffset: window.pageYOffset,
       };
-    },
-  });
+    }
+  }
+
+  customElements.define(GrCursorManager.is, GrCursorManager);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_test.html b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_test.html
index 0793ccd..103b41a 100644
--- a/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-cursor-manager/gr-cursor-manager_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-cursor-manager</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -129,7 +129,6 @@
       assert.equal(element.index, -1);
     });
 
-
     test('_moveCursor', () => {
       // Initialize the cursor with its stops.
       element.stops = list.querySelectorAll('li');
diff --git a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter.js b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter.js
index 0360145..f79c1b6 100644
--- a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter.js
+++ b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter.js
@@ -31,50 +31,56 @@
     MONTH_DAY_YEAR: 'MMM DD, YYYY', // Aug 29, 1997
   };
 
-  Polymer({
-    is: 'gr-date-formatter',
+  /**
+    * @appliesMixin Gerrit.TooltipMixin
+    */
+  class GrDateFormatter extends Polymer.mixinBehaviors( [
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-date-formatter'; }
 
-    properties: {
-      dateStr: {
-        type: String,
-        value: null,
-        notify: true,
-      },
-      showDateAndTime: {
-        type: Boolean,
-        value: false,
-      },
+    static get properties() {
+      return {
+        dateStr: {
+          type: String,
+          value: null,
+          notify: true,
+        },
+        showDateAndTime: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * When true, the detailed date appears in a GR-TOOLTIP rather than in the
        * native browser tooltip.
        */
-      hasTooltip: Boolean,
+        hasTooltip: Boolean,
 
-      /**
+        /**
        * The title to be used as the native tooltip or by the tooltip behavior.
        */
-      title: {
-        type: String,
-        reflectToAttribute: true,
-        computed: '_computeFullDateStr(dateStr, _timeFormat)',
-      },
+        title: {
+          type: String,
+          reflectToAttribute: true,
+          computed: '_computeFullDateStr(dateStr, _timeFormat)',
+        },
 
-      _timeFormat: String, // No default value to prevent flickering.
-      _relative: Boolean, // No default value to prevent flickering.
-    },
-
-    behaviors: [
-      Gerrit.TooltipBehavior,
-    ],
+        _timeFormat: String, // No default value to prevent flickering.
+        _relative: Boolean, // No default value to prevent flickering.
+      };
+    }
 
     attached() {
+      super.attached();
       this._loadPreferences();
-    },
+    }
 
     _getUtcOffsetString() {
       return ' UTC' + moment().format('Z');
-    },
+    }
 
     _loadPreferences() {
       return this._getLoggedIn().then(loggedIn => {
@@ -88,7 +94,7 @@
           this._loadRelative(),
         ]);
       });
-    },
+    }
 
     _loadTimeFormat() {
       return this._getPreferences().then(preferences => {
@@ -104,22 +110,22 @@
             throw Error('Invalid time format: ' + timeFormat);
         }
       });
-    },
+    }
 
     _loadRelative() {
       return this._getPreferences().then(prefs => {
         // prefs.relative_date_in_change_table is not set when false.
         this._relative = !!(prefs && prefs.relative_date_in_change_table);
       });
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _getPreferences() {
       return this.$.restAPI.getPreferences();
-    },
+    }
 
     /**
      * Return true if date is within 24 hours and on the same day.
@@ -127,7 +133,7 @@
     _isWithinDay(now, date) {
       const diff = -date.diff(now);
       return diff < Duration.DAY && date.day() === now.getDay();
-    },
+    }
 
     /**
      * Returns true if date is from one to six months.
@@ -136,7 +142,7 @@
       const diff = -date.diff(now);
       return (date.day() !== now.getDay() || diff >= Duration.DAY) &&
           diff < 180 * Duration.DAY;
-    },
+    }
 
     _computeDateStr(dateStr, timeFormat, relative, showDateAndTime) {
       if (!dateStr) { return ''; }
@@ -163,13 +169,13 @@
         }
       }
       return date.format(format);
-    },
+    }
 
     _timeToSecondsFormat(timeFormat) {
       return timeFormat === TimeFormats.TIME_12 ?
-          TimeFormats.TIME_12_WITH_SEC :
-          TimeFormats.TIME_24_WITH_SEC;
-    },
+        TimeFormats.TIME_12_WITH_SEC :
+        TimeFormats.TIME_24_WITH_SEC;
+    }
 
     _computeFullDateStr(dateStr, timeFormat) {
       // Polymer 2: check for undefined
@@ -186,6 +192,8 @@
       let format = TimeFormats.MONTH_DAY_YEAR + ', ';
       format += this._timeToSecondsFormat(timeFormat);
       return date.format(format) + this._getUtcOffsetString();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDateFormatter.is, GrDateFormatter);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_test.html b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_test.html
index a0bf207..fffd38e 100644
--- a/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-date-formatter/gr-date-formatter_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-date-formatter</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -89,7 +89,7 @@
     suite('24 hours time format preference', () => {
       setup(() => {
         return stubRestAPI(
-          {time_format: 'HHMM_24', relative_date_in_change_table: false}
+            {time_format: 'HHMM_24', relative_date_in_change_table: false}
         ).then(() => {
           element = fixture('basic');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
@@ -139,7 +139,7 @@
       setup(() => {
         // relative_date_in_change_table is not set when false.
         return stubRestAPI(
-          {time_format: 'HHMM_12'}
+            {time_format: 'HHMM_12'}
         ).then(() => {
           element = fixture('basic');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
@@ -159,7 +159,7 @@
     suite('relative date preference', () => {
       setup(() => {
         return stubRestAPI(
-          {time_format: 'HHMM_12', relative_date_in_change_table: true}
+            {time_format: 'HHMM_12', relative_date_in_change_table: true}
         ).then(() => {
           element = fixture('basic');
           sandbox.stub(element, '_getUtcOffsetString').returns('');
@@ -187,7 +187,7 @@
     suite('logged in', () => {
       setup(() => {
         return stubRestAPI(
-          {time_format: 'HHMM_12', relative_date_in_change_table: true}
+            {time_format: 'HHMM_12', relative_date_in_change_table: true}
         ).then(() => {
           element = fixture('basic');
           return element._loadPreferences();
diff --git a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.html b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.html
index 2ef5539..e754a55 100644
--- a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.html
+++ b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.html
@@ -32,36 +32,32 @@
         display: flex;
         flex-direction: column;
         max-height: 90vh;
+        padding: var(--spacing-xl);
       }
       header {
-        border-bottom: 1px solid var(--border-color);
         flex-shrink: 0;
-        font-weight: var(--font-weight-bold);
+        padding-bottom: var(--spacing-xl);
       }
       main {
         display: flex;
         flex-shrink: 1;
         width: 100%;
       }
-      header,
-      main,
-      footer {
-        padding: var(--spacing-m) var(--spacing-xl);
-      }
-      gr-button {
-        margin-left: var(--spacing-l);
-      }
       footer {
         display: flex;
         flex-shrink: 0;
         justify-content: flex-end;
+        padding-top: var(--spacing-xl);
+      }
+      gr-button {
+        margin-left: var(--spacing-l);
       }
       .hidden {
         display: none;
       }
     </style>
     <div class="container" on-keydown="_handleKeydown">
-      <header><slot name="header"></slot></header>
+      <header class="font-h3"><slot name="header"></slot></header>
       <main><slot name="main"></slot></main>
       <footer>
         <gr-button id="cancel" class$="[[_computeCancelClass(cancelLabel)]]" link on-click="_handleCancelTap">
diff --git a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.js b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.js
index 68dc537..b84434e 100644
--- a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.js
+++ b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog.js
@@ -17,9 +17,15 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-dialog',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrDialog extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-dialog'; }
     /**
      * Fired when the confirm button is pressed.
      *
@@ -32,33 +38,32 @@
      * @event cancel
      */
 
-    properties: {
-      confirmLabel: {
-        type: String,
-        value: 'Confirm',
-      },
-      // Supplying an empty cancel label will hide the button completely.
-      cancelLabel: {
-        type: String,
-        value: 'Cancel',
-      },
-      disabled: {
-        type: Boolean,
-        value: false,
-      },
-      confirmOnEnter: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        confirmLabel: {
+          type: String,
+          value: 'Confirm',
+        },
+        // Supplying an empty cancel label will hide the button completely.
+        cancelLabel: {
+          type: String,
+          value: 'Cancel',
+        },
+        disabled: {
+          type: Boolean,
+          value: false,
+        },
+        confirmOnEnter: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    hostAttributes: {
-      role: 'dialog',
-    },
+    ready() {
+      super.ready();
+      this._ensureAttribute('role', 'dialog');
+    }
 
     _handleConfirm(e) {
       if (this.disabled) { return; }
@@ -66,24 +71,26 @@
       e.preventDefault();
       e.stopPropagation();
       this.fire('confirm', null, {bubbles: false});
-    },
+    }
 
     _handleCancelTap(e) {
       e.preventDefault();
       e.stopPropagation();
       this.fire('cancel', null, {bubbles: false});
-    },
+    }
 
     _handleKeydown(e) {
       if (this.confirmOnEnter && e.keyCode === 13) { this._handleConfirm(e); }
-    },
+    }
 
     resetFocus() {
       this.$.confirm.focus();
-    },
+    }
 
     _computeCancelClass(cancelLabel) {
       return cancelLabel.length ? '' : 'hidden';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDialog.is, GrDialog);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_test.html b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_test.html
index 1456e77..ced925e 100644
--- a/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-dialog/gr-dialog_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-dialog</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.html b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.html
index 9d85d44..367e30c 100644
--- a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.html
+++ b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.html
@@ -24,8 +24,12 @@
 
 <dom-module id="gr-diff-preferences">
   <template>
-    <style include="shared-styles"></style>
-    <style include="gr-form-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
+    <style include="gr-form-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <div id="diffPreferences" class="gr-form-styles">
       <section>
         <span class="title">Context</span>
diff --git a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.js b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.js
index 36fdf5b..6e34bbc 100644
--- a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.js
+++ b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences.js
@@ -17,62 +17,68 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-diff-preferences',
+  class GrDiffPreferences extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-diff-preferences'; }
 
-    properties: {
-      hasUnsavedChanges: {
-        type: Boolean,
-        notify: true,
-        value: false,
-      },
+    static get properties() {
+      return {
+        hasUnsavedChanges: {
+          type: Boolean,
+          notify: true,
+          value: false,
+        },
 
-      /** @type {?} */
-      diffPrefs: Object,
-    },
+        /** @type {?} */
+        diffPrefs: Object,
+      };
+    }
 
     loadData() {
       return this.$.restAPI.getDiffPreferences().then(prefs => {
         this.diffPrefs = prefs;
       });
-    },
+    }
 
     _handleDiffPrefsChanged() {
       this.hasUnsavedChanges = true;
-    },
+    }
 
     _handleLineWrappingTap() {
       this.set('diffPrefs.line_wrapping', this.$.lineWrappingInput.checked);
       this._handleDiffPrefsChanged();
-    },
+    }
 
     _handleShowTabsTap() {
       this.set('diffPrefs.show_tabs', this.$.showTabsInput.checked);
       this._handleDiffPrefsChanged();
-    },
+    }
 
     _handleShowTrailingWhitespaceTap() {
       this.set('diffPrefs.show_whitespace_errors',
           this.$.showTrailingWhitespaceInput.checked);
       this._handleDiffPrefsChanged();
-    },
+    }
 
     _handleSyntaxHighlightTap() {
       this.set('diffPrefs.syntax_highlighting',
           this.$.syntaxHighlightInput.checked);
       this._handleDiffPrefsChanged();
-    },
+    }
 
     _handleAutomaticReviewTap() {
       this.set('diffPrefs.manual_review',
           !this.$.automaticReviewInput.checked);
       this._handleDiffPrefsChanged();
-    },
+    }
 
     save() {
       return this.$.restAPI.saveDiffPreferences(this.diffPrefs).then(res => {
         this.hasUnsavedChanges = false;
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDiffPreferences.is, GrDiffPreferences);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_test.html b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_test.html
index f7b10e0..fa1ade5 100644
--- a/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-diff-preferences/gr-diff-preferences_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-diff-preferences</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -110,7 +110,7 @@
           .returns(Promise.resolve());
       const showTrailingWhitespaceCheckbox =
           valueOf('Show trailing whitespace', 'diffPreferences')
-          .firstElementChild;
+              .firstElementChild;
       showTrailingWhitespaceCheckbox.checked = false;
       element._handleShowTrailingWhitespaceTap();
 
diff --git a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands.js b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands.js
index 121aa35..8ee4820 100644
--- a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands.js
+++ b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands.js
@@ -17,40 +17,46 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-download-commands',
+  /**
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrDownloadCommands extends Polymer.mixinBehaviors( [
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-download-commands'; }
 
-    properties: {
-      commands: Array,
-      _loggedIn: {
-        type: Boolean,
-        value: false,
-        observer: '_loggedInChanged',
-      },
-      schemes: Array,
-      selectedScheme: {
-        type: String,
-        notify: true,
-      },
-    },
-
-    behaviors: [
-      Gerrit.RESTClientBehavior,
-    ],
+    static get properties() {
+      return {
+        commands: Array,
+        _loggedIn: {
+          type: Boolean,
+          value: false,
+          observer: '_loggedInChanged',
+        },
+        schemes: Array,
+        selectedScheme: {
+          type: String,
+          notify: true,
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       this._getLoggedIn().then(loggedIn => {
         this._loggedIn = loggedIn;
       });
-    },
+    }
 
     focusOnCopy() {
       this.$$('gr-shell-command').focusOnCopy();
-    },
+    }
 
     _getLoggedIn() {
       return this.$.restAPI.getLoggedIn();
-    },
+    }
 
     _loggedInChanged(loggedIn) {
       if (!loggedIn) { return; }
@@ -60,7 +66,7 @@
           this.selectedScheme = prefs.download_scheme.toLowerCase();
         }
       });
-    },
+    }
 
     _handleTabChange(e) {
       const scheme = this.schemes[e.detail.value];
@@ -71,15 +77,17 @@
               {download_scheme: this.selectedScheme});
         }
       }
-    },
+    }
 
     _computeSelected(schemes, selectedScheme) {
       return (schemes.findIndex(scheme => scheme === selectedScheme) || 0)
           + '';
-    },
+    }
 
     _computeShowTabs(schemes) {
       return schemes.length > 1 ? '' : 'hidden';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDownloadCommands.is, GrDownloadCommands);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_test.html b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_test.html
index 85a5b1f..7d4b341 100644
--- a/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-download-commands/gr-download-commands_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-download-commands</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.html b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.html
index 98d7bf6..7fffcff 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.html
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.html
@@ -142,7 +142,7 @@
       <paper-listbox
           class="dropdown-content"
           slot="dropdown-content"
-          attr-for-selected="value"
+          attr-for-selected="data-value"
           selected="{{value}}"
           on-tap="_handleDropdownTap">
         <template is="dom-repeat"
@@ -150,7 +150,7 @@
             initial-count="[[initialCount]]">
           <paper-item
               disabled="[[item.disabled]]"
-              value="[[item.value]]">
+              data-value$="[[item.value]]">
             <div class="topContent">
               <div>[[item.text]]</div>
               <template is="dom-if" if="[[item.date]]">
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.js b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.js
index 3b5e25f..6272a67 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.js
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list.js
@@ -45,9 +45,10 @@
    */
   Defs.item;
 
-  Polymer({
-    is: 'gr-dropdown-list',
-
+  class GrDropdownList extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-dropdown-list'; }
     /**
      * Fired when the selected value changes
      *
@@ -56,24 +57,28 @@
      * @property {string|number} value
      */
 
-    properties: {
-      initialCount: Number,
-      /** @type {!Array<!Defs.item>} */
-      items: Object,
-      text: String,
-      disabled: {
-        type: Boolean,
-        value: false,
-      },
-      value: {
-        type: String,
-        notify: true,
-      },
-    },
+    static get properties() {
+      return {
+        initialCount: Number,
+        /** @type {!Array<!Defs.item>} */
+        items: Object,
+        text: String,
+        disabled: {
+          type: Boolean,
+          value: false,
+        },
+        value: {
+          type: String,
+          notify: true,
+        },
+      };
+    }
 
-    observers: [
-      '_handleValueChange(value, items)',
-    ],
+    static get observers() {
+      return [
+        '_handleValueChange(value, items)',
+      ];
+    }
 
     /**
      * Handle a click on the iron-dropdown element.
@@ -85,7 +90,7 @@
       this.async(() => {
         this.$.dropdown.close();
       }, 1);
-    },
+    }
 
     /**
      * Handle a click on the button to open the dropdown.
@@ -93,18 +98,18 @@
      */
     _showDropdownTapHandler(e) {
       this._open();
-    },
+    }
 
     /**
      * Open the dropdown.
      */
     _open() {
       this.$.dropdown.open();
-    },
+    }
 
     _computeMobileText(item) {
       return item.mobileText ? item.mobileText : item.text;
-    },
+    }
 
     _handleValueChange(value, items) {
       // Polymer 2: check for undefined
@@ -118,11 +123,13 @@
       });
       if (!selectedObj) { return; }
       this.text = selectedObj.triggerText? selectedObj.triggerText :
-          selectedObj.text;
+        selectedObj.text;
       this.dispatchEvent(new CustomEvent('value-change', {
         detail: {value},
         bubbles: false,
       }));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDropdownList.is, GrDropdownList);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_test.html b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_test.html
index 2b63d99..8d098df 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown-list/gr-dropdown-list_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-dropdown-list</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -109,7 +109,7 @@
 
         assert.isNotOk(Polymer.dom(items[0]).querySelector('gr-date-formatter'));
         assert.isNotOk(Polymer.dom(items[0]).querySelector('.bottomContent'));
-        assert.equal(items[0].value, element.items[0].value);
+        assert.equal(items[0].dataset.value, element.items[0].value);
         assert.equal(mobileItems[0].value, element.items[0].value);
         assert.equal(Polymer.dom(items[0]).querySelector('.topContent div')
             .innerText, element.items[0].text);
@@ -117,7 +117,6 @@
         // Since no mobile specific text, it should fall back to text.
         assert.equal(mobileItems[0].text, element.items[0].text);
 
-
         // Second Item
         // The second item should have top text, bottom text, and no date.
         assert.isFalse(!!items[1].disabled);
@@ -127,7 +126,7 @@
 
         assert.isNotOk(Polymer.dom(items[1]).querySelector('gr-date-formatter'));
         assert.isOk(Polymer.dom(items[1]).querySelector('.bottomContent'));
-        assert.equal(items[1].value, element.items[1].value);
+        assert.equal(items[1].dataset.value, element.items[1].value);
         assert.equal(mobileItems[1].value, element.items[1].value);
         assert.equal(Polymer.dom(items[1]).querySelector('.topContent div')
             .innerText, element.items[1].text);
@@ -148,7 +147,7 @@
 
         assert.isOk(Polymer.dom(items[2]).querySelector('gr-date-formatter'));
         assert.isOk(Polymer.dom(items[2]).querySelector('.bottomContent'));
-        assert.equal(items[2].value, element.items[2].value);
+        assert.equal(items[2].dataset.value, element.items[2].value);
         assert.equal(mobileItems[2].value, element.items[2].value);
         assert.equal(Polymer.dom(items[2]).querySelector('.topContent div')
             .innerText, element.items[2].text);
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown.js b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown.js
index 615acd7..fc92e76 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown.js
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown.js
@@ -20,9 +20,17 @@
   const REL_NOOPENER = 'noopener';
   const REL_EXTERNAL = 'external';
 
-  Polymer({
-    is: 'gr-dropdown',
-
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrDropdown extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-dropdown'; }
     /**
      * Fired when a non-link dropdown item with the given ID is tapped.
      *
@@ -35,60 +43,59 @@
      * @event tap-item
      */
 
-    properties: {
-      items: {
-        type: Array,
-        observer: '_resetCursorStops',
-      },
-      downArrow: Boolean,
-      topContent: Object,
-      horizontalAlign: {
-        type: String,
-        value: 'left',
-      },
+    static get properties() {
+      return {
+        items: {
+          type: Array,
+          observer: '_resetCursorStops',
+        },
+        downArrow: Boolean,
+        topContent: Object,
+        horizontalAlign: {
+          type: String,
+          value: 'left',
+        },
 
-      /**
+        /**
        * Style the dropdown trigger as a link (rather than a button).
        */
-      link: {
-        type: Boolean,
-        value: false,
-      },
+        link: {
+          type: Boolean,
+          value: false,
+        },
 
-      verticalOffset: {
-        type: Number,
-        value: 40,
-      },
+        verticalOffset: {
+          type: Number,
+          value: 40,
+        },
 
-      /**
+        /**
        * List the IDs of dropdown buttons to be disabled. (Note this only
        * diisables bittons and not link entries.)
        */
-      disabledIds: {
-        type: Array,
-        value() { return []; },
-      },
+        disabledIds: {
+          type: Array,
+          value() { return []; },
+        },
 
-      /**
+        /**
        * The elements of the list.
        */
-      _listElements: {
-        type: Array,
-        value() { return []; },
-      },
-    },
+        _listElements: {
+          type: Array,
+          value() { return []; },
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    keyBindings: {
-      'down': '_handleDown',
-      'enter space': '_handleEnter',
-      'tab': '_handleTab',
-      'up': '_handleUp',
-    },
+    get keyBindings() {
+      return {
+        'down': '_handleDown',
+        'enter space': '_handleEnter',
+        'tab': '_handleTab',
+        'up': '_handleUp',
+      };
+    }
 
     /**
      * Handle the up key.
@@ -102,7 +109,7 @@
       } else {
         this._open();
       }
-    },
+    }
 
     /**
      * Handle the down key.
@@ -116,7 +123,7 @@
       } else {
         this._open();
       }
-    },
+    }
 
     /**
      * Handle the tab key.
@@ -128,7 +135,7 @@
         e.preventDefault();
         e.stopPropagation();
       }
-    },
+    }
 
     /**
      * Handle the enter key.
@@ -146,7 +153,7 @@
       } else {
         this._open();
       }
-    },
+    }
 
     /**
      * Handle a click on the iron-dropdown element.
@@ -154,7 +161,7 @@
      */
     _handleDropdownClick(e) {
       this._close();
-    },
+    }
 
     /**
      * Hanlde a click on the button to open the dropdown.
@@ -168,7 +175,7 @@
       } else {
         this._open();
       }
-    },
+    }
 
     /**
      * Open the dropdown and initialize the cursor.
@@ -178,7 +185,7 @@
       this._resetCursorStops();
       this.$.cursor.setCursorAtIndex(0);
       this.$.cursor.target.focus();
-    },
+    }
 
     _close() {
       // async is needed so that that the click event is fired before the
@@ -186,7 +193,7 @@
       this.async(() => {
         this.$.dropdown.close();
       }, 1);
-    },
+    }
 
     /**
      * Get the class for a top-content item based on the given boolean.
@@ -195,7 +202,7 @@
      */
     _getClassIfBold(bold) {
       return bold ? 'bold-text' : '';
-    },
+    }
 
     /**
      * Build a URL for the given host and path. The base URL will be only added,
@@ -206,9 +213,9 @@
      */
     _computeURLHelper(host, path) {
       const base = path.startsWith(this.getBaseUrl()) ?
-          '' : this.getBaseUrl();
+        '' : this.getBaseUrl();
       return '//' + host + base + path;
-    },
+    }
 
     /**
      * Build a scheme-relative URL for the current host. Will include the base
@@ -220,7 +227,7 @@
     _computeRelativeURL(path) {
       const host = window.location.host;
       return this._computeURLHelper(host, path);
-    },
+    }
 
     /**
      * Compute the URL for a link object.
@@ -235,7 +242,7 @@
         return link.url;
       }
       return this._computeRelativeURL(link.url);
-    },
+    }
 
     /**
      * Compute the value for the rel attribute of an anchor for the given link
@@ -249,7 +256,7 @@
       if (link.target) { return REL_NOOPENER; }
       if (link.external) { return REL_EXTERNAL; }
       return null;
-    },
+    }
 
     /**
      * Handle a click on an item of the dropdown.
@@ -264,7 +271,7 @@
         }
         this.dispatchEvent(new CustomEvent('tap-item-' + id));
       }
-    },
+    }
 
     /**
      * If a dropdown item is shown as a button, get the class for the button.
@@ -275,7 +282,7 @@
      */
     _computeDisabledClass(id, disabledIdsRecord) {
       return disabledIdsRecord.base.includes(id) ? 'disabled' : '';
-    },
+    }
 
     /**
      * Recompute the stops for the dropdown item cursor.
@@ -286,14 +293,16 @@
         this._listElements = Array.from(
             Polymer.dom(this.root).querySelectorAll('li'));
       }
-    },
+    }
 
     _computeHasTooltip(tooltip) {
       return !!tooltip;
-    },
+    }
 
     _computeIsDownload(link) {
       return !!link.download;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrDropdown.is, GrDropdown);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_test.html b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_test.html
index 295f746..4b5ccb4 100644
--- a/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-dropdown/gr-dropdown_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-dropdown</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content.js b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content.js
index 1e339dc..49b1025 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content.js
+++ b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content.js
@@ -20,9 +20,15 @@
   const RESTORED_MESSAGE = 'Content restored from a previous edit.';
   const STORAGE_DEBOUNCE_INTERVAL_MS = 400;
 
-  Polymer({
-    is: 'gr-editable-content',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrEditableContent extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-editable-content'; }
     /**
      * Fired when the save button is pressed.
      *
@@ -41,42 +47,40 @@
      * @event show-alert
      */
 
-    properties: {
-      content: {
-        notify: true,
-        type: String,
-      },
-      disabled: {
-        reflectToAttribute: true,
-        type: Boolean,
-        value: false,
-      },
-      editing: {
-        observer: '_editingChanged',
-        type: Boolean,
-        value: false,
-      },
-      removeZeroWidthSpace: Boolean,
-      // If no storage key is provided, content is not stored.
-      storageKey: String,
-      _saveDisabled: {
-        computed: '_computeSaveDisabled(disabled, content, _newContent)',
-        type: Boolean,
-        value: true,
-      },
-      _newContent: {
-        type: String,
-        observer: '_newContentChanged',
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+    static get properties() {
+      return {
+        content: {
+          notify: true,
+          type: String,
+        },
+        disabled: {
+          reflectToAttribute: true,
+          type: Boolean,
+          value: false,
+        },
+        editing: {
+          observer: '_editingChanged',
+          type: Boolean,
+          value: false,
+        },
+        removeZeroWidthSpace: Boolean,
+        // If no storage key is provided, content is not stored.
+        storageKey: String,
+        _saveDisabled: {
+          computed: '_computeSaveDisabled(disabled, content, _newContent)',
+          type: Boolean,
+          value: true,
+        },
+        _newContent: {
+          type: String,
+          observer: '_newContentChanged',
+        },
+      };
+    }
 
     focusTextarea() {
       this.$$('iron-autogrow-textarea').textarea.focus();
-    },
+    }
 
     _newContentChanged(newContent, oldContent) {
       if (!this.storageKey) { return; }
@@ -88,7 +92,7 @@
           this.$.storage.eraseEditableContentItem(this.storageKey);
         }
       }, STORAGE_DEBOUNCE_INTERVAL_MS);
-    },
+    }
 
     _editingChanged(editing) {
       if (!editing) { return; }
@@ -112,9 +116,9 @@
 
       // TODO(wyatta) switch linkify sequence, see issue 5526.
       this._newContent = this.removeZeroWidthSpace ?
-          content.replace(/^R=\u200B/gm, 'R=') :
-          content;
-    },
+        content.replace(/^R=\u200B/gm, 'R=') :
+        content;
+    }
 
     _computeSaveDisabled(disabled, content, newContent) {
       // Polymer 2: check for undefined
@@ -127,17 +131,19 @@
       }
 
       return disabled || (content === newContent);
-    },
+    }
 
     _handleSave(e) {
       e.preventDefault();
       this.fire('editable-content-save', {content: this._newContent});
-    },
+    }
 
     _handleCancel(e) {
       e.preventDefault();
       this.editing = false;
       this.fire('editable-content-cancel');
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditableContent.is, GrEditableContent);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_test.html b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_test.html
index 24db69f..69c9a00 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-editable-content/gr-editable-content_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-editable-content</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label.js b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label.js
index 4485551..b989401 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label.js
+++ b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label.js
@@ -20,76 +20,84 @@
   const AWAIT_MAX_ITERS = 10;
   const AWAIT_STEP = 5;
 
-  Polymer({
-    is: 'gr-editable-label',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrEditableLabel extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-editable-label'; }
     /**
      * Fired when the value is changed.
      *
      * @event changed
      */
 
-    properties: {
-      labelText: String,
-      editing: {
-        type: Boolean,
-        value: false,
-      },
-      value: {
-        type: String,
-        notify: true,
-        value: '',
-        observer: '_updateTitle',
-      },
-      placeholder: {
-        type: String,
-        value: '',
-      },
-      readOnly: {
-        type: Boolean,
-        value: false,
-      },
-      uppercase: {
-        type: Boolean,
-        reflectToAttribute: true,
-        value: false,
-      },
-      maxLength: Number,
-      _inputText: String,
-      // This is used to push the iron-input element up on the page, so
-      // the input is placed in approximately the same position as the
-      // trigger.
-      _verticalOffset: {
-        type: Number,
-        readOnly: true,
-        value: -30,
-      },
-    },
+    static get properties() {
+      return {
+        labelText: String,
+        editing: {
+          type: Boolean,
+          value: false,
+        },
+        value: {
+          type: String,
+          notify: true,
+          value: '',
+          observer: '_updateTitle',
+        },
+        placeholder: {
+          type: String,
+          value: '',
+        },
+        readOnly: {
+          type: Boolean,
+          value: false,
+        },
+        uppercase: {
+          type: Boolean,
+          reflectToAttribute: true,
+          value: false,
+        },
+        maxLength: Number,
+        _inputText: String,
+        // This is used to push the iron-input element up on the page, so
+        // the input is placed in approximately the same position as the
+        // trigger.
+        _verticalOffset: {
+          type: Number,
+          readOnly: true,
+          value: -30,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
+    ready() {
+      super.ready();
+      this._ensureAttribute('tabindex', '0');
+    }
 
-    keyBindings: {
-      enter: '_handleEnter',
-      esc: '_handleEsc',
-    },
-
-    hostAttributes: {
-      tabindex: '0',
-    },
+    get keyBindings() {
+      return {
+        enter: '_handleEnter',
+        esc: '_handleEsc',
+      };
+    }
 
     _usePlaceholder(value, placeholder) {
       return (!value || !value.length) && placeholder;
-    },
+    }
 
     _computeLabel(value, placeholder) {
       if (this._usePlaceholder(value, placeholder)) {
         return placeholder;
       }
       return value;
-    },
+    }
 
     _showDropdown() {
       if (this.readOnly || this.editing) { return; }
@@ -98,13 +106,13 @@
         if (!this.$.input.value) { return; }
         this._nativeInput.setSelectionRange(0, this.$.input.value.length);
       });
-    },
+    }
 
     open() {
       return this._open().then(() => {
         this._nativeInput.focus();
       });
-    },
+    }
 
     _open(...args) {
       this.$.dropdown.open();
@@ -115,7 +123,7 @@
         Polymer.IronOverlayBehaviorImpl.open.apply(this.$.dropdown, args);
         this._awaitOpen(resolve);
       });
-    },
+    }
 
     /**
      * NOTE: (wyatta) Slightly hacky way to listen to the overlay actually
@@ -133,11 +141,11 @@
         }, AWAIT_STEP);
       };
       step.call(this);
-    },
+    }
 
     _id() {
       return this.getAttribute('id') || 'global';
-    },
+    }
 
     _save() {
       if (!this.editing) { return; }
@@ -145,20 +153,20 @@
       this.value = this._inputText;
       this.editing = false;
       this.fire('changed', this.value);
-    },
+    }
 
     _cancel() {
       if (!this.editing) { return; }
       this.$.dropdown.close();
       this.editing = false;
       this._inputText = this.value;
-    },
+    }
 
     get _nativeInput() {
       // In Polymer 2, the namespace of nativeInput
       // changed from input to nativeInput
       return this.$.input.$.nativeInput || this.$.input.$.input;
-    },
+    }
 
     _handleEnter(e) {
       e = this.getKeyboardEvent(e);
@@ -167,7 +175,7 @@
         e.preventDefault();
         this._save();
       }
-    },
+    }
 
     _handleEsc(e) {
       e = this.getKeyboardEvent(e);
@@ -176,7 +184,7 @@
         e.preventDefault();
         this._cancel();
       }
-    },
+    }
 
     _computeLabelClass(readOnly, value, placeholder) {
       const classes = [];
@@ -185,10 +193,12 @@
         classes.push('placeholder');
       }
       return classes.join(' ');
-    },
+    }
 
     _updateTitle(value) {
       this.setAttribute('title', this._computeLabel(value, this.placeholder));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrEditableLabel.is, GrEditableLabel);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_test.html b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_test.html
index 7ff0a14..1690c3a 100644
--- a/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-editable-label/gr-editable-label_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-editable-label</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -166,7 +166,6 @@
       MockInteractions.tap(element.$.saveBtn, 13);
     });
 
-
     test('edit and then escape key', done => {
       const editedStub = sandbox.stub();
       element.addEventListener('changed', editedStub);
diff --git a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel.js b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel.js
index 2c32709..af533bc 100644
--- a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel.js
+++ b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel.js
@@ -17,47 +17,52 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-fixed-panel',
+  class GrFixedPanel extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-fixed-panel'; }
 
-    properties: {
-      floatingDisabled: Boolean,
-      readyForMeasure: {
-        type: Boolean,
-        observer: '_readyForMeasureObserver',
-      },
-      keepOnScroll: {
-        type: Boolean,
-        value: false,
-      },
-      _isMeasured: {
-        type: Boolean,
-        value: false,
-      },
+    static get properties() {
+      return {
+        floatingDisabled: Boolean,
+        readyForMeasure: {
+          type: Boolean,
+          observer: '_readyForMeasureObserver',
+        },
+        keepOnScroll: {
+          type: Boolean,
+          value: false,
+        },
+        _isMeasured: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * Initial offset from the top of the document, in pixels.
        */
-      _topInitial: Number,
+        _topInitial: Number,
 
-      /**
+        /**
        * Current offset from the top of the window, in pixels.
        */
-      _topLast: Number,
+        _topLast: Number,
 
-      _headerHeight: Number,
-      _headerFloating: {
-        type: Boolean,
-        value: false,
-      },
-      _observer: {
-        type: Object,
-        value: null,
-      },
-      _webComponentsReady: Boolean,
-    },
+        _headerHeight: Number,
+        _headerFloating: {
+          type: Boolean,
+          value: false,
+        },
+        _observer: {
+          type: Object,
+          value: null,
+        },
+        _webComponentsReady: Boolean,
+      };
+    }
 
     attached() {
+      super.attached();
       if (this.floatingDisabled) {
         return;
       }
@@ -69,21 +74,22 @@
       this.listen(window, 'scroll', '_updateOnScroll');
       this._observer = new MutationObserver(this.update.bind(this));
       this._observer.observe(this.$.header, {childList: true, subtree: true});
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'scroll', '_updateOnScroll');
       this.unlisten(window, 'resize', 'update');
       if (this._observer) {
         this._observer.disconnect();
       }
-    },
+    }
 
     _readyForMeasureObserver(readyForMeasure) {
       if (readyForMeasure) {
         this.update();
       }
-    },
+    }
 
     _computeHeaderClass(headerFloating, topLast) {
       const fixedAtTop = this.keepOnScroll && topLast === 0;
@@ -91,7 +97,7 @@
         headerFloating ? 'floating' : '',
         fixedAtTop ? 'fixedAtTop' : '',
       ].join(' ');
-    },
+    }
 
     unfloat() {
       if (this.floatingDisabled) {
@@ -100,19 +106,19 @@
       this.$.header.style.top = '';
       this._headerFloating = false;
       this.updateStyles({'--header-height': ''});
-    },
+    }
 
     update() {
       this.debounce('update', () => {
         this._updateDebounced();
       }, 100);
-    },
+    }
 
     _updateOnScroll() {
       this.debounce('update', () => {
         this._updateDebounced();
       });
-    },
+    }
 
     _updateDebounced() {
       if (this.floatingDisabled) {
@@ -121,11 +127,11 @@
       this._isMeasured = false;
       this._maybeFloatHeader();
       this._reposition();
-    },
+    }
 
     _getElementTop() {
       return this.getBoundingClientRect().top;
-    },
+    }
 
     _reposition() {
       if (!this._headerFloating) {
@@ -155,7 +161,7 @@
         }
         this._topLast = newTop;
       }
-    },
+    }
 
     _measure() {
       if (this._isMeasured) {
@@ -171,12 +177,12 @@
       this._topInitial =
         this.getBoundingClientRect().top + document.body.scrollTop;
       this._isMeasured = true;
-    },
+    }
 
     _isFloatingNeeded() {
       return this.keepOnScroll ||
         document.body.scrollWidth > document.body.clientWidth;
-    },
+    }
 
     _maybeFloatHeader() {
       if (!this._isFloatingNeeded()) {
@@ -186,11 +192,13 @@
       if (this._isMeasured) {
         this._floatHeader();
       }
-    },
+    }
 
     _floatHeader() {
       this.updateStyles({'--header-height': this._headerHeight + 'px'});
       this._headerFloating = true;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrFixedPanel.is, GrFixedPanel);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_test.html b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_test.html
index 75e9901..419b3e7 100644
--- a/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-fixed-panel/gr-fixed-panel_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-fixed-panel</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.js b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.js
index 4e68d42..7730a75 100644
--- a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.js
+++ b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.js
@@ -20,30 +20,37 @@
   // eslint-disable-next-line no-unused-vars
   const QUOTE_MARKER_PATTERN = /\n\s?>\s/g;
 
-  Polymer({
-    is: 'gr-formatted-text',
+  class GrFormattedText extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-formatted-text'; }
 
-    properties: {
-      content: {
-        type: String,
-        observer: '_contentChanged',
-      },
-      config: Object,
-      noTrailingMargin: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        content: {
+          type: String,
+          observer: '_contentChanged',
+        },
+        config: Object,
+        noTrailingMargin: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    observers: [
-      '_contentOrConfigChanged(content, config)',
-    ],
+    static get observers() {
+      return [
+        '_contentOrConfigChanged(content, config)',
+      ];
+    }
 
     ready() {
+      super.ready();
       if (this.noTrailingMargin) {
         this.classList.add('noTrailingMargin');
       }
-    },
+    }
 
     /**
      * Get the plain text as it appears in the generated DOM.
@@ -56,7 +63,7 @@
      */
     getTextContent() {
       return this._blocksToText(this._computeBlocks(this.content));
-    },
+    }
 
     _contentChanged(content) {
       // In the case where the config may not be set (perhaps due to the
@@ -64,7 +71,7 @@
       // prevent waiting on the config to display the text.
       if (this.config) { return; }
       this._contentOrConfigChanged(content);
-    },
+    }
 
     /**
      * Given a source string, update the DOM inside #container.
@@ -81,7 +88,7 @@
       for (const node of this._computeNodes(this._computeBlocks(content))) {
         container.appendChild(node);
       }
-    },
+    }
 
     /**
      * Given a source string, parse into an array of block objects. Each block
@@ -127,7 +134,7 @@
         }
       }
       return result;
-    },
+    }
 
     /**
      * Take a block of comment text that contains a list and potentially
@@ -201,7 +208,7 @@
       if (block !== null) {
         out.push(block);
       }
-    },
+    }
 
     _makeQuote(p) {
       const quotedLines = p
@@ -212,21 +219,21 @@
         type: 'quote',
         blocks: this._computeBlocks(quotedLines),
       };
-    },
+    }
 
     _isQuote(p) {
       return p.startsWith('> ') || p.startsWith(' > ');
-    },
+    }
 
     _isPreFormat(p) {
       return p.includes('\n ') || p.includes('\n\t') ||
           p.startsWith(' ') || p.startsWith('\t');
-    },
+    }
 
     _isList(p) {
       return p.includes('\n- ') || p.includes('\n* ') ||
           p.startsWith('- ') || p.startsWith('* ');
-    },
+    }
 
     /**
      * @param {string} content
@@ -241,7 +248,7 @@
         text.classList.add('pre');
       }
       return text;
-    },
+    }
 
     /**
      * Map an array of block objects to an array of DOM nodes.
@@ -278,7 +285,7 @@
           return ul;
         }
       });
-    },
+    }
 
     _blocksToText(blocks) {
       return blocks.map(block => {
@@ -292,6 +299,8 @@
           return block.items.join('\n');
         }
       }).join('\n\n');
-    },
-  });
+    }
+  }
+
+  customElements.define(GrFormattedText.is, GrFormattedText);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.html b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.html
index 801190a..92fbc74 100644
--- a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-editable-label</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard.js b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard.js
index 1b31e89..5e3cfb3 100644
--- a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard.js
+++ b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard.js
@@ -25,82 +25,90 @@
    */
   const DIAGONAL_OVERFLOW = 15;
 
-  Polymer({
-    is: 'gr-hovercard',
+  class GrHovercard extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-hovercard'; }
 
-    properties: {
+    static get properties() {
+      return {
       /**
        * @type {?}
        */
-      _target: Object,
+        _target: Object,
 
-      /**
+        /**
        * Determines whether or not the hovercard is visible.
        *
        * @type {boolean}
        */
-      _isShowing: {
-        type: Boolean,
-        value: false,
-      },
-      /**
+        _isShowing: {
+          type: Boolean,
+          value: false,
+        },
+        /**
        * The `id` of the element that the hovercard is anchored to.
        *
        * @type {string}
        */
-      for: {
-        type: String,
-        observer: '_forChanged',
-      },
+        for: {
+          type: String,
+          observer: '_forChanged',
+        },
 
-      /**
+        /**
        * The spacing between the top of the hovercard and the element it is
        * anchored to.
        *
        * @type {number}
        */
-      offset: {
-        type: Number,
-        value: 14,
-      },
+        offset: {
+          type: Number,
+          value: 14,
+        },
 
-      /**
+        /**
        * Positions the hovercard to the top, right, bottom, left, bottom-left,
        * bottom-right, top-left, or top-right of its content.
        *
        * @type {string}
        */
-      position: {
-        type: String,
-        value: 'bottom',
-      },
+        position: {
+          type: String,
+          value: 'bottom',
+        },
 
-      container: Object,
-      /**
+        container: Object,
+        /**
        * ID for the container element.
        *
        * @type {string}
        */
-      containerId: {
-        type: String,
-        value: 'gr-hovercard-container',
-      },
-    },
-
-    listeners: {
-      mouseleave: 'hide',
-    },
+        containerId: {
+          type: String,
+          value: 'gr-hovercard-container',
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       if (!this._target) { this._target = this.target; }
       this.listen(this._target, 'mouseenter', 'show');
       this.listen(this._target, 'focus', 'show');
       this.listen(this._target, 'mouseleave', 'hide');
       this.listen(this._target, 'blur', 'hide');
       this.listen(this._target, 'click', 'hide');
-    },
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('mouseleave',
+          e => this.hide(e));
+    }
 
     ready() {
+      super.ready();
       // First, check to see if the container has already been created.
       this.container = Gerrit.getRootElement()
           .querySelector('#' + this.containerId);
@@ -111,7 +119,7 @@
       this.container = document.createElement('div');
       this.container.setAttribute('id', this.containerId);
       Gerrit.getRootElement().appendChild(this.container);
-    },
+    }
 
     removeListeners() {
       this.unlisten(this._target, 'mouseenter', 'show');
@@ -119,7 +127,7 @@
       this.unlisten(this._target, 'mouseleave', 'hide');
       this.unlisten(this._target, 'blur', 'hide');
       this.unlisten(this._target, 'click', 'hide');
-    },
+    }
 
     /**
      * Returns the target element that the hovercard is anchored to (the `id` of
@@ -136,11 +144,11 @@
         target = Polymer.dom(ownerRoot).querySelector('#' + this.for);
       } else {
         target = parentNode.nodeType == Node.DOCUMENT_FRAGMENT_NODE ?
-            ownerRoot.host :
-            parentNode;
+          ownerRoot.host :
+          parentNode;
       }
       return target;
-    },
+    }
 
     /**
      * Hides/closes the hovercard. This occurs when the user triggers the
@@ -184,7 +192,7 @@
       if (this.container.contains(this)) {
         this.container.removeChild(this);
       }
-    },
+    }
 
     /**
      * Shows/opens the hovercard. This occurs when the user triggers the
@@ -207,7 +215,7 @@
 
       // Trigger the transition
       this.classList.add(HOVER_CLASS);
-    },
+    }
 
     /**
      * Updates the hovercard's position based on the `position` attribute
@@ -244,7 +252,7 @@
           hovercardLeft = targetLeft + (targetRect.width - thisRect.width) / 2;
           hovercardTop = targetTop - thisRect.height - this.offset;
           cssText += `padding-bottom:${this.offset
-              }px; margin-bottom:-${this.offset}px;`;
+          }px; margin-bottom:-${this.offset}px;`;
           break;
         case 'bottom':
           hovercardLeft = targetLeft + (targetRect.width - thisRect.width) / 2;
@@ -306,7 +314,7 @@
       // Set the hovercard's position
       cssText += `left:${hovercardLeft}px; top:${hovercardTop}px;`;
       this.style.cssText = cssText;
-    },
+    }
 
     /**
      * Responds to a change in the `for` value and gets the updated `target`
@@ -316,6 +324,8 @@
      */
     _forChanged() {
       this._target = this.target;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrHovercard.is, GrHovercard);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_test.html b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_test.html
index 8e79f65..35d736c 100644
--- a/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-hovercard/gr-hovercard_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-hovercard</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-icons/gr-icons.html b/polygerrit-ui/app/elements/shared/gr-icons/gr-icons.html
index 7bd6f48..743923b 100644
--- a/polygerrit-ui/app/elements/shared/gr-icons/gr-icons.html
+++ b/polygerrit-ui/app/elements/shared/gr-icons/gr-icons.html
@@ -76,6 +76,7 @@
       <g id="restore"><path d="M12,8 L12,13 L16.28,15.54 L17,14.33 L13.5,12.25 L13.5,8 L12,8 Z M13,3 C8.03,3 4,7.03 4,12 L1,12 L4.89,15.89 L4.96,16.03 L9,12 L6,12 C6,8.13 9.13,5 13,5 C16.87,5 20,8.13 20,12 C20,15.87 16.87,19 13,19 C11.07,19 9.32,18.21 8.06,16.94 L6.64,18.36 C8.27,19.99 10.51,21 13,21 C17.97,21 22,16.97 22,12 C22,7.03 17.97,3 13,3 Z"></path></g>
       <!-- This is a custom PolyGerrit SVG -->
       <g id="revert"><path d="M12.3,8.5 C9.64999995,8.5 7.24999995,9.49 5.39999995,11.1 L1.79999995,7.5 L1.79999995,16.5 L10.8,16.5 L7.17999995,12.88 C8.56999995,11.72 10.34,11 12.3,11 C15.84,11 18.85,13.31 19.9,16.5 L22.27,15.72 C20.88,11.53 16.95,8.5 12.3,8.5"></path></g>
+      <g id="revert_submission"><path d="M12.3,8.5 C9.64999995,8.5 7.24999995,9.49 5.39999995,11.1 L1.79999995,7.5 L1.79999995,16.5 L10.8,16.5 L7.17999995,12.88 C8.56999995,11.72 10.34,11 12.3,11 C15.84,11 18.85,13.31 19.9,16.5 L22.27,15.72 C20.88,11.53 16.95,8.5 12.3,8.5"></path></g>
       <!-- This is a custom PolyGerrit SVG -->
       <g id="stopEdit"><path d="M4 4 20 4 20 20 4 20z"></path></g>
       <!-- This is a custom PolyGerrit SVG -->
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.html
index 3223636..66e7a74 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-context_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-annotation-actions-context</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.js
index 98268c5..b5ff46d 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api.js
@@ -156,7 +156,7 @@
   GrAnnotationActionsInterface.prototype.getLayer = function(
       path, changeNum, patchNum) {
     const annotationLayer = new AnnotationLayer(path, changeNum, patchNum,
-                                                this._addLayerFunc);
+        this._addLayerFunc);
     this._annotationLayers.push(annotationLayer);
     return annotationLayer;
   };
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.html
index 987b551..98ff954 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-annotation-actions-js-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-annotation-actions-js-api-js-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils.js
index 4123f70..2d66cfa 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils.js
@@ -90,7 +90,6 @@
     });
   }
 
-
   // TEST only methods / properties
 
   function testOnly_resetInternalState() {
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.html
index c407aa8..128738d 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-api-utils_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-api-interface</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -29,7 +29,6 @@
 <script>void(0);</script>
 
 <script>
-
   const PRELOADED_PROTOCOL = 'preloaded:';
 
   suite('gr-api-utils tests', () => {
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.html
index 7332877..cbe2d37 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-actions-js-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-actions-js-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.html
index 842a2fe..7955aa4 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-change-reply-js-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-change-reply-js-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit.js
index 03eb2e8..546b9f3 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit.js
@@ -15,7 +15,7 @@
  * limitations under the License.
  */
 
- /**
+/**
   * This defines the Gerrit instance. All methods directly attached to Gerrit
   * should be defined or linked here.
   */
@@ -25,8 +25,8 @@
 
   // Import utils methods
   const {
-      send,
-      getRestAPI,
+    send,
+    getRestAPI,
   } = window._apiUtils;
 
   /**
@@ -54,7 +54,7 @@
       testOnly_resetInternalState,
     } = window._apiUtils;
     Gerrit._testOnly_installPreloadedPlugins = (...args) => Gerrit._pluginLoader
-      .installPreloadedPlugins(...args);
+        .installPreloadedPlugins(...args);
     Gerrit._testOnly_flushPreinstalls = flushPreinstalls;
     Gerrit._testOnly_resetPlugins = () => {
       testOnly_resetInternalState();
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.html
index e81b8aa..7b03308 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-gerrit_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-api-interface</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface.js
index 70a7a01..1802a4a 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface.js
@@ -25,6 +25,7 @@
     COMMIT_MSG_EDIT: 'commitmsgedit',
     COMMENT: 'comment',
     REVERT: 'revert',
+    REVERT_SUBMISSION: 'revert_submission',
     POST_REVERT: 'postrevert',
     ANNOTATE_DIFF: 'annotatediff',
     ADMIN_MENU_LINKS: 'admin-menu-links',
@@ -36,24 +37,34 @@
     REPLY_DIALOG: 'replydialog',
   };
 
-  Polymer({
-    is: 'gr-js-api-interface',
+  /**
+    * @appliesMixin Gerrit.PatchSetMixin
+    */
+  class GrJsApiInterface extends Polymer.mixinBehaviors( [
+    Gerrit.PatchSetBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-js-api-interface'; }
 
-    properties: {
-      _elements: {
-        type: Object,
-        value: {}, // Shared across all instances.
-      },
-      _eventCallbacks: {
-        type: Object,
-        value: {}, // Shared across all instances.
-      },
-    },
+    constructor() {
+      super();
+      this.Element = Element;
+      this.EventType = EventType;
+    }
 
-    behaviors: [Gerrit.PatchSetBehavior],
-
-    Element,
-    EventType,
+    static get properties() {
+      return {
+        _elements: {
+          type: Object,
+          value: {}, // Shared across all instances.
+        },
+        _eventCallbacks: {
+          type: Object,
+          value: {}, // Shared across all instances.
+        },
+      };
+    }
 
     handleEvent(type, detail) {
       Gerrit.awaitPluginsLoaded().then(() => {
@@ -79,22 +90,22 @@
             break;
         }
       });
-    },
+    }
 
     addElement(key, el) {
       this._elements[key] = el;
-    },
+    }
 
     getElement(key) {
       return this._elements[key];
-    },
+    }
 
     addEventCallback(eventName, callback) {
       if (!this._eventCallbacks[eventName]) {
         this._eventCallbacks[eventName] = [];
       }
       this._eventCallbacks[eventName].push(callback);
-    },
+    }
 
     canSubmitChange(change, revision) {
       const submitCallbacks = this._getEventCallbacks(EventType.SUBMIT_CHANGE);
@@ -108,14 +119,14 @@
       });
 
       return !cancelSubmit;
-    },
+    }
 
     _removeEventCallbacks() {
       for (const k in EventType) {
         if (!EventType.hasOwnProperty(k)) { continue; }
         this._eventCallbacks[EventType[k]] = [];
       }
-    },
+    }
 
     _handleHistory(detail) {
       for (const cb of this._getEventCallbacks(EventType.HISTORY)) {
@@ -125,7 +136,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     _handleShowChange(detail) {
       // Note (issue 8221) Shallow clone the change object and add a mergeable
@@ -160,7 +171,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     handleCommitMessage(change, msg) {
       for (const cb of this._getEventCallbacks(EventType.COMMIT_MSG_EDIT)) {
@@ -170,7 +181,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     _handleComment(detail) {
       for (const cb of this._getEventCallbacks(EventType.COMMENT)) {
@@ -180,7 +191,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     _handleLabelChange(detail) {
       for (const cb of this._getEventCallbacks(EventType.LABEL_CHANGE)) {
@@ -190,7 +201,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     _handleHighlightjsLoaded(detail) {
       for (const cb of this._getEventCallbacks(EventType.HIGHLIGHTJS_LOADED)) {
@@ -200,7 +211,7 @@
           console.error(err);
         }
       }
-    },
+    }
 
     modifyRevertMsg(change, revertMsg, origMsg) {
       for (const cb of this._getEventCallbacks(EventType.REVERT)) {
@@ -211,12 +222,23 @@
         }
       }
       return revertMsg;
-    },
+    }
+
+    modifyRevertSubmissionMsg(change, revertSubmissionMsg, origMsg) {
+      for (const cb of this._getEventCallbacks(EventType.REVERT_SUBMISSION)) {
+        try {
+          revertSubmissionMsg = cb(change, revertSubmissionMsg, origMsg);
+        } catch (err) {
+          console.error(err);
+        }
+      }
+      return revertSubmissionMsg;
+    }
 
     getDiffLayers(path, changeNum, patchNum) {
       const layers = [];
       for (const annotationApi of
-           this._getEventCallbacks(EventType.ANNOTATE_DIFF)) {
+        this._getEventCallbacks(EventType.ANNOTATE_DIFF)) {
         try {
           const layer = annotationApi.getLayer(path, changeNum, patchNum);
           layers.push(layer);
@@ -225,7 +247,7 @@
         }
       }
       return layers;
-    },
+    }
 
     /**
      * Retrieves coverage data possibly provided by a plugin.
@@ -243,7 +265,7 @@
     getCoverageRanges(changeNum, path, basePatchNum, patchNum) {
       return Gerrit.awaitPluginsLoaded().then(() => {
         for (const annotationApi of
-            this._getEventCallbacks(EventType.ANNOTATE_DIFF)) {
+          this._getEventCallbacks(EventType.ANNOTATE_DIFF)) {
           const provider = annotationApi.getCoverageProvider();
           // Only one coverage provider makes sense. If there are more, then we
           // simply ignore them.
@@ -253,16 +275,16 @@
         }
         return [];
       });
-    },
+    }
 
     getAdminMenuLinks() {
       const links = [];
       for (const adminApi of
-          this._getEventCallbacks(EventType.ADMIN_MENU_LINKS)) {
+        this._getEventCallbacks(EventType.ADMIN_MENU_LINKS)) {
         links.push(...adminApi.getMenuLinks());
       }
       return links;
-    },
+    }
 
     getLabelValuesPostRevert(change) {
       let labels = {};
@@ -274,10 +296,12 @@
         }
       }
       return labels;
-    },
+    }
 
     _getEventCallbacks(type) {
       return this._eventCallbacks[type] || [];
-    },
-  });
+    }
+  }
+
+  customElements.define(GrJsApiInterface.is, GrJsApiInterface);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.html
index ae12940..537e55b 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-js-api-interface_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-api-interface</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.html
index 6da117f..f7b7cf8 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-action-context_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-action-context</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints.js
index 8832a3f..4b7778c 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints.js
@@ -33,7 +33,7 @@
   GrPluginEndpoints.prototype._getOrCreateModuleInfo = function(plugin,
       endpoint, type, moduleName, domHook) {
     const existingModule = this._endpoints[endpoint].find(info =>
-        info.plugin === plugin &&
+      info.plugin === plugin &&
         info.moduleName === moduleName &&
         info.domHook === domHook
     );
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints_test.html
index 8ed7f14..b39ed6d 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-endpoints_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-endpoints</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader.js
index fef026a..4be38b6 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader.js
@@ -20,10 +20,10 @@
 
   // Import utils methods
   const {
-      PLUGIN_LOADING_TIMEOUT_MS,
-      PRELOADED_PROTOCOL,
-      getPluginNameFromUrl,
-      getBaseUrl,
+    PLUGIN_LOADING_TIMEOUT_MS,
+    PRELOADED_PROTOCOL,
+    getPluginNameFromUrl,
+    getBaseUrl,
   } = window._apiUtils;
 
   /**
@@ -328,7 +328,7 @@
     _createScriptTag(url) {
       const el = document.createElement('script');
       el.defer = true;
-      el.src = url;
+      el.setAttribute('src', url);
       el.onerror = () => this._failToLoad(`${url} load error`, url);
       return document.body.appendChild(el);
     }
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.html
index ee54319..8c1ec96 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-loader_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-host</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -367,7 +367,6 @@
         );
       });
 
-
       test('relative path should honor getBaseUrl', () => {
         const testUrl = '/test';
         sandbox.stub(Gerrit.BaseUrlBehavior, 'getBaseUrl', () => {
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.html b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.html
index bcbd961..4aae032 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-plugin-rest-api_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-plugin-rest-api</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-public-js-api.js b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-public-js-api.js
index d76c983..6c306d9 100644
--- a/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-public-js-api.js
+++ b/polygerrit-ui/app/elements/shared/gr-js-api-interface/gr-public-js-api.js
@@ -26,8 +26,8 @@
 
   // Import utils methods
   const {
-      getPluginNameFromUrl,
-      send,
+    getPluginNameFromUrl,
+    send,
   } = window._apiUtils;
 
   /**
@@ -113,7 +113,7 @@
   Plugin.prototype._registerCustomComponent = function(
       endpointName, opt_moduleName, opt_options, dynamicEndpoint) {
     const type = opt_options && opt_options.replace ?
-          EndpointType.REPLACE : EndpointType.DECORATE;
+      EndpointType.REPLACE : EndpointType.DECORATE;
     const hook = this._domHooks.getDomHook(endpointName, opt_moduleName);
     const moduleName = opt_moduleName || hook.getModuleName();
     Gerrit._endpoints.registerModule(
@@ -184,14 +184,14 @@
 
   Plugin.prototype.changeActions = function() {
     return new GrChangeActionsInterface(this,
-      Plugin._sharedAPIElement.getElement(
-          Plugin._sharedAPIElement.Element.CHANGE_ACTIONS));
+        Plugin._sharedAPIElement.getElement(
+            Plugin._sharedAPIElement.Element.CHANGE_ACTIONS));
   };
 
   Plugin.prototype.changeReply = function() {
     return new GrChangeReplyInterface(this,
-      Plugin._sharedAPIElement.getElement(
-          Plugin._sharedAPIElement.Element.REPLY_DIALOG));
+        Plugin._sharedAPIElement.getElement(
+            Plugin._sharedAPIElement.Element.REPLY_DIALOG));
   };
 
   Plugin.prototype.changeView = function() {
diff --git a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.html b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.html
index 63a528e..b17b251 100644
--- a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.html
+++ b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.html
@@ -28,7 +28,9 @@
 
 <dom-module id="gr-label-info">
   <template strip-whitespace>
-    <style include="gr-voting-styles"></style>
+    <style include="gr-voting-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style include="shared-styles">
       .placeholder {
         color: var(--deemphasized-text-color);
diff --git a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.js b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.js
index 3eb44e6..0e529b1 100644
--- a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.js
+++ b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info.js
@@ -17,17 +17,21 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-label-info',
+  class GrLabelInfo extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-label-info'; }
 
-    properties: {
-      labelInfo: Object,
-      label: String,
-      /** @type {?} */
-      change: Object,
-      account: Object,
-      mutable: Boolean,
-    },
+    static get properties() {
+      return {
+        labelInfo: Object,
+        label: String,
+        /** @type {?} */
+        change: Object,
+        account: Object,
+        mutable: Boolean,
+      };
+    }
 
     /**
      * @param {!Object} labelInfo
@@ -85,7 +89,7 @@
         }
       }
       return result;
-    },
+    }
 
     /**
      * A user is able to delete a vote iff the mutable property is true and the
@@ -106,7 +110,7 @@
         return '';
       }
       return 'hidden';
-    },
+    }
 
     /**
      * Closure annotation for Polymer.prototype.splice is off.
@@ -125,22 +129,22 @@
       const accountID = parseInt(target.getAttribute('data-account-id'), 10);
       this._xhrPromise =
           this.$.restAPI.deleteVote(this.change._number, accountID, this.label)
-          .then(response => {
-            target.disabled = false;
-            if (!response.ok) { return; }
-            Gerrit.Nav.navigateToChange(this.change);
-          }).catch(err => {
-            target.disabled = false;
-            return;
-          });
-    },
+              .then(response => {
+                target.disabled = false;
+                if (!response.ok) { return; }
+                Gerrit.Nav.navigateToChange(this.change);
+              }).catch(err => {
+                target.disabled = false;
+                return;
+              });
+    }
 
     _computeValueTooltip(labelInfo, score) {
       if (!labelInfo || !labelInfo.values || !labelInfo.values[score]) {
         return '';
       }
       return labelInfo.values[score];
-    },
+    }
 
     /**
      * @param {!Object} labelInfo
@@ -156,6 +160,8 @@
         }
       }
       return '';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLabelInfo.is, GrLabelInfo);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_test.html b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_test.html
index 35dc772..adf88d9 100644
--- a/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-label-info/gr-label-info_test.html
@@ -17,7 +17,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-label-info</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-label/gr-label.js b/polygerrit-ui/app/elements/shared/gr-label/gr-label.js
index 0de0881..7d82c9c9 100644
--- a/polygerrit-ui/app/elements/shared/gr-label/gr-label.js
+++ b/polygerrit-ui/app/elements/shared/gr-label/gr-label.js
@@ -17,11 +17,16 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-label',
+  /**
+    * @appliesMixin Gerrit.TooltipMixin
+    */
+  class GrLabel extends Polymer.mixinBehaviors( [
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-label'; }
+  }
 
-    behaviors: [
-      Gerrit.TooltipBehavior,
-    ],
-  });
+  customElements.define(GrLabel.is, GrLabel);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.html b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.html
index da0b93f..47be6f7 100644
--- a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.html
+++ b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.html
@@ -38,14 +38,7 @@
       #body {
         display: flex;
       }
-      gr-autocomplete {
-        height: 1.5em;
-        --gr-autocomplete: {
-          border: none;
-        }
-      }
       #trigger {
-        border-left: 1px solid var(--deemphasized-text-color);
         color: var(--deemphasized-text-color);
         cursor: pointer;
         padding-left: var(--spacing-s);
diff --git a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.js b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.js
index fd0f228..d2646af 100644
--- a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.js
+++ b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete.js
@@ -17,60 +17,65 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-labeled-autocomplete',
-
+  class GrLabeledAutocomplete extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-labeled-autocomplete'; }
     /**
      * Fired when a value is chosen.
      *
      * @event commit
      */
 
-    properties: {
+    static get properties() {
+      return {
 
-      /**
+        /**
        * Used just like the query property of gr-autocomplete.
        *
        * @type {function(string): Promise<?>}
        */
-      query: {
-        type: Function,
-        value() {
-          return function() {
-            return Promise.resolve([]);
-          };
+        query: {
+          type: Function,
+          value() {
+            return function() {
+              return Promise.resolve([]);
+            };
+          },
         },
-      },
 
-      text: {
-        type: String,
-        value: '',
-        notify: true,
-      },
-      label: String,
-      placeholder: String,
-      disabled: Boolean,
+        text: {
+          type: String,
+          value: '',
+          notify: true,
+        },
+        label: String,
+        placeholder: String,
+        disabled: Boolean,
 
-      _autocompleteThreshold: {
-        type: Number,
-        value: 0,
-        readOnly: true,
-      },
-    },
+        _autocompleteThreshold: {
+          type: Number,
+          value: 0,
+          readOnly: true,
+        },
+      };
+    }
 
     _handleTriggerClick(e) {
       // Stop propagation here so we don't confuse gr-autocomplete, which
       // listens for taps on body to try to determine when it's blurred.
       e.stopPropagation();
       this.$.autocomplete.focus();
-    },
+    }
 
     setText(text) {
       this.$.autocomplete.setText(text);
-    },
+    }
 
     clear() {
       this.setText('');
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLabeledAutocomplete.is, GrLabeledAutocomplete);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_test.html b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_test.html
index b257746..7e8f73f 100644
--- a/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-labeled-autocomplete/gr-labeled-autocomplete_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-labeled-autocomplete</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader.js b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader.js
index 853a299..1fd122c 100644
--- a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader.js
+++ b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader.js
@@ -20,21 +20,25 @@
   const HLJS_PATH = 'bower_components/highlightjs/highlight.min.js';
   const DARK_THEME_PATH = 'styles/themes/dark-theme.html';
 
-  Polymer({
-    is: 'gr-lib-loader',
+  class GrLibLoader extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-lib-loader'; }
 
-    properties: {
-      _hljsState: {
-        type: Object,
+    static get properties() {
+      return {
+        _hljsState: {
+          type: Object,
 
-        // NOTE: intended singleton.
-        value: {
-          configured: false,
-          loading: false,
-          callbacks: [],
+          // NOTE: intended singleton.
+          value: {
+            configured: false,
+            loading: false,
+            callbacks: [],
+          },
         },
-      },
-    },
+      };
+    }
 
     /**
      * Get the HLJS library. Returns a promise that resolves with a reference to
@@ -59,7 +63,7 @@
 
         this._hljsState.callbacks.push(resolve);
       });
-    },
+    }
 
     /**
      * Loads the dark theme document. Returns a promise that resolves with a
@@ -71,12 +75,15 @@
       return new Promise((resolve, reject) => {
         (this.importHref || Polymer.importHref)(
             this._getLibRoot() + DARK_THEME_PATH, () => {
-              const module = document.createElement('style', 'custom-style');
+              const module = document.createElement('style');
               module.setAttribute('include', 'dark-theme');
-              resolve(module);
+              const cs = document.createElement('custom-style');
+              cs.appendChild(module);
+
+              resolve(cs);
             });
       });
-    },
+    }
 
     /**
      * Execute callbacks awaiting the HLJS lib load.
@@ -91,7 +98,7 @@
         cb(lib);
       }
       this._hljsState.callbacks = [];
-    },
+    }
 
     /**
      * Get the HLJS library, assuming it has been loaded. Configure the library
@@ -106,7 +113,7 @@
         lib.configure({classPrefix: 'gr-diff gr-syntax gr-syntax-'});
       }
       return lib;
-    },
+    }
 
     /**
      * Get the resource path used to load the application. If the application
@@ -118,7 +125,7 @@
         return window.STATIC_RESOURCE_PATH + '/';
       }
       return '/';
-    },
+    }
 
     /**
      * Load and execute a JS file from the lib root.
@@ -140,12 +147,14 @@
         script.onerror = reject;
         Polymer.dom(document.head).appendChild(script);
       });
-    },
+    }
 
     _getHLJSUrl() {
       const root = this._getLibRoot();
       if (!root) { return null; }
       return root + HLJS_PATH;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLibLoader.is, GrLibLoader);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_test.html b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_test.html
index 10d1608..832a558 100644
--- a/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-lib-loader/gr-lib-loader_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-lib-loader</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text.js b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text.js
index 048e4f5..9239866 100644
--- a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text.js
+++ b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text.js
@@ -17,57 +17,63 @@
 (function() {
   'use strict';
 
+  /**
+    * @appliesMixin Gerrit.TooltipMixin
+    */
   /*
    * The gr-limited-text element is for displaying text with a maximum length
    * (in number of characters) to display. If the length of the text exceeds the
    * configured limit, then an ellipsis indicates that the text was truncated
    * and a tooltip containing the full text is enabled.
    */
+  class GrLimitedText extends Polymer.mixinBehaviors( [
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-limited-text'; }
 
-  Polymer({
-    is: 'gr-limited-text',
-
-    properties: {
+    static get properties() {
+      return {
       /** The un-truncated text to display. */
-      text: String,
+        text: String,
 
-      /** The maximum length for the text to display before truncating. */
-      limit: {
-        type: Number,
-        value: null,
-      },
+        /** The maximum length for the text to display before truncating. */
+        limit: {
+          type: Number,
+          value: null,
+        },
 
-      /** Boolean property used by Gerrit.TooltipBehavior. */
-      hasTooltip: {
-        type: Boolean,
-        value: false,
-      },
+        /** Boolean property used by Gerrit.TooltipBehavior. */
+        hasTooltip: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * Disable the tooltip.
        * When set to true, will not show tooltip even text is over limit
        */
-      disableTooltip: {
-        type: Boolean,
-        value: false,
-      },
+        disableTooltip: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**
+        /**
        * The maximum number of characters to display in the tooltop.
        */
-      tooltipLimit: {
-        type: Number,
-        value: 1024,
-      },
-    },
+        tooltipLimit: {
+          type: Number,
+          value: 1024,
+        },
+      };
+    }
 
-    observers: [
-      '_updateTitle(text, limit, tooltipLimit)',
-    ],
-
-    behaviors: [
-      Gerrit.TooltipBehavior,
-    ],
+    static get observers() {
+      return [
+        '_updateTitle(text, limit, tooltipLimit)',
+      ];
+    }
 
     /**
      * The text or limit have changed. Recompute whether a tooltip needs to be
@@ -85,13 +91,15 @@
       } else {
         this.removeAttribute('title');
       }
-    },
+    }
 
     _computeDisplayText(text, limit) {
       if (!!limit && !!text && text.length > limit) {
         return text.substr(0, limit - 1) + '…';
       }
       return text;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLimitedText.is, GrLimitedText);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_test.html b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_test.html
index 7946bb6..3ba30d1 100644
--- a/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-limited-text/gr-limited-text_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-limited-text</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip.js b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip.js
index 33a9c25..aaae3d1 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip.js
+++ b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip.js
@@ -17,41 +17,48 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-linked-chip',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrLinkedChip extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-linked-chip'; }
 
-    properties: {
-      href: String,
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      removable: {
-        type: Boolean,
-        value: false,
-      },
-      text: String,
-      transparentBackground: {
-        type: Boolean,
-        value: false,
-      },
+    static get properties() {
+      return {
+        href: String,
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        removable: {
+          type: Boolean,
+          value: false,
+        },
+        text: String,
+        transparentBackground: {
+          type: Boolean,
+          value: false,
+        },
 
-      /**  If provided, sets the maximum length of the content. */
-      limit: Number,
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
+        /**  If provided, sets the maximum length of the content. */
+        limit: Number,
+      };
+    }
 
     _getBackgroundClass(transparent) {
       return transparent ? 'transparentBackground' : '';
-    },
+    }
 
     _handleRemoveTap(e) {
       e.preventDefault();
       this.fire('remove');
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLinkedChip.is, GrLinkedChip);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_test.html b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_test.html
index 22a2eaf..733e897 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-linked-chip/gr-linked-chip_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-linked-chip</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text.js b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text.js
index e7247b9..25f406e 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text.js
+++ b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text.js
@@ -17,31 +17,37 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-linked-text',
+  class GrLinkedText extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-linked-text'; }
 
-    properties: {
-      removeZeroWidthSpace: Boolean,
-      content: {
-        type: String,
-        observer: '_contentChanged',
-      },
-      pre: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      disabled: {
-        type: Boolean,
-        value: false,
-        reflectToAttribute: true,
-      },
-      config: Object,
-    },
+    static get properties() {
+      return {
+        removeZeroWidthSpace: Boolean,
+        content: {
+          type: String,
+          observer: '_contentChanged',
+        },
+        pre: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        disabled: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
+        config: Object,
+      };
+    }
 
-    observers: [
-      '_contentOrConfigChanged(content, config)',
-    ],
+    static get observers() {
+      return [
+        '_contentOrConfigChanged(content, config)',
+      ];
+    }
 
     _contentChanged(content) {
       // In the case where the config may not be set (perhaps due to the
@@ -49,7 +55,7 @@
       // prevent waiting on the config to display the text.
       if (this.config != null) { return; }
       this.$.output.textContent = content;
-    },
+    }
 
     /**
      * Because either the source text or the linkification config has changed,
@@ -74,7 +80,7 @@
         anchor.setAttribute('target', '_blank');
         anchor.setAttribute('rel', 'noopener');
       });
-    },
+    }
 
     /**
      * This method is called when the GrLikTextParser emits a partial result
@@ -100,6 +106,8 @@
       } else if (fragment) {
         output.appendChild(fragment);
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrLinkedText.is, GrLinkedText);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_test.html b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_test.html
index f01a75c..e9477bf 100644
--- a/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-linked-text/gr-linked-text_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-linked-text</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view.js b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view.js
index 8d81030..9d5d8f5 100644
--- a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view.js
+++ b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view.js
@@ -19,31 +19,39 @@
 
   const REQUEST_DEBOUNCE_INTERVAL_MS = 200;
 
-  Polymer({
-    is: 'gr-list-view',
+  /**
+    * @appliesMixin Gerrit.BaseUrlMixin
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrListView extends Polymer.mixinBehaviors( [
+    Gerrit.BaseUrlBehavior,
+    Gerrit.FireBehavior,
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-list-view'; }
 
-    properties: {
-      createNew: Boolean,
-      items: Array,
-      itemsPerPage: Number,
-      filter: {
-        type: String,
-        observer: '_filterChanged',
-      },
-      offset: Number,
-      loading: Boolean,
-      path: String,
-    },
-
-    behaviors: [
-      Gerrit.BaseUrlBehavior,
-      Gerrit.FireBehavior,
-      Gerrit.URLEncodingBehavior,
-    ],
+    static get properties() {
+      return {
+        createNew: Boolean,
+        items: Array,
+        itemsPerPage: Number,
+        filter: {
+          type: String,
+          observer: '_filterChanged',
+        },
+        offset: Number,
+        loading: Boolean,
+        path: String,
+      };
+    }
 
     detached() {
+      super.detached();
       this.cancelDebouncer('reload');
-    },
+    }
 
     _filterChanged(newFilter, oldFilter) {
       if (!newFilter && !oldFilter) {
@@ -51,7 +59,7 @@
       }
 
       this._debounceReload(newFilter);
-    },
+    }
 
     _debounceReload(filter) {
       this.debounce('reload', () => {
@@ -61,11 +69,11 @@
         }
         page.show(this.path);
       }, REQUEST_DEBOUNCE_INTERVAL_MS);
-    },
+    }
 
     _createNewItem() {
       this.fire('create-clicked');
-    },
+    }
 
     _computeNavLink(offset, direction, itemsPerPage, filter, path) {
       // Offset could be a string when passed from the router.
@@ -79,15 +87,15 @@
         href += ',' + newOffset;
       }
       return href;
-    },
+    }
 
     _computeCreateClass(createNew) {
       return createNew ? 'show' : '';
-    },
+    }
 
     _hidePrevArrow(loading, offset) {
       return loading || offset === 0;
-    },
+    }
 
     _hideNextArrow(loading, items) {
       if (loading || !items || !items.length) {
@@ -95,6 +103,8 @@
       }
       const lastPage = items.length < this.itemsPerPage + 1;
       return lastPage;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrListView.is, GrListView);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_test.html b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_test.html
index c67d8b2..8f87b38 100644
--- a/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-list-view/gr-list-view_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-list-view</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 <script src="/bower_components/page/page.js"></script>
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.html b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.html
index 2b4b982..46b8fb6 100644
--- a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.html
+++ b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.html
@@ -25,7 +25,10 @@
     <style include="shared-styles">
       :host {
         background: var(--dialog-background-color);
-        box-shadow: rgba(0, 0, 0, 0.3) 0 1px 3px;
+        border-radius: var(--border-radius);
+        box-shadow: 0 11px 15px -7px rgba(0,0,0,.2),
+                    0 24px 38px  3px rgba(0,0,0,.14),
+                    0  9px 46px  8px rgba(0,0,0,.12);
       }
 
       @media screen and (max-width: 50em) {
@@ -35,6 +38,8 @@
           position: fixed;
           right: 0;
           top: 0;
+          border-radius: 0;
+          box-shadow: none;
         }
       }
     </style>
diff --git a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.js b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.js
index 8623458..9c7e680 100644
--- a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.js
+++ b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay.js
@@ -21,9 +21,16 @@
   const AWAIT_STEP = 5;
   const BREAKPOINT_FULLSCREEN_OVERLAY = '50em';
 
-  Polymer({
-    is: 'gr-overlay',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrOverlay extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Polymer.IronOverlayBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-overlay'; }
     /**
      * Fired when a fullscreen overlay is closed
      *
@@ -36,22 +43,22 @@
      * @event fullscreen-overlay-opened
      */
 
-    properties: {
-      _fullScreenOpen: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        _fullScreenOpen: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Polymer.IronOverlayBehavior,
-    ],
-
-    listeners: {
-      'iron-overlay-closed': '_close',
-      'iron-overlay-cancelled': '_close',
-    },
+    created() {
+      super.created();
+      this.addEventListener('iron-overlay-closed',
+          () => this._close());
+      this.addEventListener('iron-overlay-cancelled',
+          () => this._close());
+    }
 
     open(...args) {
       return new Promise(resolve => {
@@ -62,18 +69,18 @@
         }
         this._awaitOpen(resolve);
       });
-    },
+    }
 
     _isMobile() {
       return window.matchMedia(`(max-width: ${BREAKPOINT_FULLSCREEN_OVERLAY})`);
-    },
+    }
 
     _close() {
       if (this._fullScreenOpen) {
         this.fire('fullscreen-overlay-closed');
         this._fullScreenOpen = false;
       }
-    },
+    }
 
     /**
      * Override the focus stops that iron-overlay-behavior tries to find.
@@ -81,7 +88,7 @@
     setFocusStops(stops) {
       this.__firstFocusableNode = stops.start;
       this.__lastFocusableNode = stops.end;
-    },
+    }
 
     /**
      * NOTE: (wyatta) Slightly hacky way to listen to the overlay actually
@@ -99,10 +106,12 @@
         }, AWAIT_STEP);
       };
       step.call(this);
-    },
+    }
 
     _id() {
       return this.getAttribute('id') || 'global';
-    },
-  });
+    }
+  }
+
+  customElements.define(GrOverlay.is, GrOverlay);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_test.html b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_test.html
index 08b7497..659823f 100644
--- a/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-overlay/gr-overlay_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-overlay</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav.js b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav.js
index 9ccff600..23389ee 100644
--- a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav.js
+++ b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav.js
@@ -17,27 +17,33 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-page-nav',
+  class GrPageNav extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-page-nav'; }
 
-    properties: {
-      _headerHeight: Number,
-    },
+    static get properties() {
+      return {
+        _headerHeight: Number,
+      };
+    }
 
     attached() {
+      super.attached();
       this.listen(window, 'scroll', '_handleBodyScroll');
-    },
+    }
 
     detached() {
+      super.detached();
       this.unlisten(window, 'scroll', '_handleBodyScroll');
-    },
+    }
 
     _handleBodyScroll() {
       if (this._headerHeight === undefined) {
         let top = this._getOffsetTop(this);
         for (let offsetParent = this.offsetParent;
-           offsetParent;
-           offsetParent = this._getOffsetParent(offsetParent)) {
+          offsetParent;
+          offsetParent = this._getOffsetParent(offsetParent)) {
           top += this._getOffsetTop(offsetParent);
         }
         this._headerHeight = top;
@@ -45,20 +51,22 @@
 
       this.$.nav.classList.toggle('pinned',
           this._getScrollY() >= this._headerHeight);
-    },
+    }
 
     /* Functions used for test purposes */
     _getOffsetParent(element) {
       if (!element || !element.offsetParent) { return ''; }
       return element.offsetParent;
-    },
+    }
 
     _getOffsetTop(element) {
       return element.offsetTop;
-    },
+    }
 
     _getScrollY() {
       return window.scrollY;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrPageNav.is, GrPageNav);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_test.html b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_test.html
index b384b47..663d3bd 100644
--- a/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-page-nav/gr-page-nav_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-page-nav</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/page/page.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker.js b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker.js
index e2298c3..47979f1 100644
--- a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker.js
+++ b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker.js
@@ -20,47 +20,54 @@
   const SUGGESTIONS_LIMIT = 15;
   const REF_PREFIX = 'refs/heads/';
 
-  Polymer({
-    is: 'gr-repo-branch-picker',
+  /**
+    * @appliesMixin Gerrit.URLEncodingMixin
+    */
+  class GrRepoBranchPicker extends Polymer.mixinBehaviors( [
+    Gerrit.URLEncodingBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-repo-branch-picker'; }
 
-    properties: {
-      repo: {
-        type: String,
-        notify: true,
-        observer: '_repoChanged',
-      },
-      branch: {
-        type: String,
-        notify: true,
-      },
-      _branchDisabled: Boolean,
-      _query: {
-        type: Function,
-        value() {
-          return this._getRepoBranchesSuggestions.bind(this);
+    static get properties() {
+      return {
+        repo: {
+          type: String,
+          notify: true,
+          observer: '_repoChanged',
         },
-      },
-      _repoQuery: {
-        type: Function,
-        value() {
-          return this._getRepoSuggestions.bind(this);
+        branch: {
+          type: String,
+          notify: true,
         },
-      },
-    },
-
-    behaviors: [
-      Gerrit.URLEncodingBehavior,
-    ],
+        _branchDisabled: Boolean,
+        _query: {
+          type: Function,
+          value() {
+            return this._getRepoBranchesSuggestions.bind(this);
+          },
+        },
+        _repoQuery: {
+          type: Function,
+          value() {
+            return this._getRepoSuggestions.bind(this);
+          },
+        },
+      };
+    }
 
     attached() {
+      super.attached();
       if (this.repo) {
         this.$.repoInput.setText(this.repo);
       }
-    },
+    }
 
     ready() {
+      super.ready();
       this._branchDisabled = !this.repo;
-    },
+    }
 
     _getRepoBranchesSuggestions(input) {
       if (!this.repo) { return Promise.resolve([]); }
@@ -69,19 +76,19 @@
       }
       return this.$.restAPI.getRepoBranches(input, this.repo, SUGGESTIONS_LIMIT)
           .then(this._branchResponseToSuggestions.bind(this));
-    },
+    }
 
     _getRepoSuggestions(input) {
       return this.$.restAPI.getRepos(input, SUGGESTIONS_LIMIT)
           .then(this._repoResponseToSuggestions.bind(this));
-    },
+    }
 
     _repoResponseToSuggestions(res) {
       return res.map(repo => ({
         name: repo.name,
         value: this.singleDecodeURL(repo.id),
       }));
-    },
+    }
 
     _branchResponseToSuggestions(res) {
       return Object.keys(res).map(key => {
@@ -91,19 +98,21 @@
         }
         return {name: branch, value: branch};
       });
-    },
+    }
 
     _repoCommitted(e) {
       this.repo = e.detail.value;
-    },
+    }
 
     _branchCommitted(e) {
       this.branch = e.detail.value;
-    },
+    }
 
     _repoChanged() {
       this.$.branchInput.clear();
       this._branchDisabled = !this.repo;
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRepoBranchPicker.is, GrRepoBranchPicker);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_test.html b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_test.html
index 1ed9151..e7252d6 100644
--- a/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-repo-branch-picker/gr-repo-branch-picker_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-repo-branch-picker</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth.js b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth.js
index 43e3922..0084932 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth.js
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth.js
@@ -76,7 +76,8 @@
       }, this._defaultOptions, opt_options);
       if (this._type === Gerrit.Auth.TYPE.ACCESS_TOKEN) {
         return this._getAccessToken().then(
-            accessToken => this._fetchWithAccessToken(url, options, accessToken)
+            accessToken =>
+              this._fetchWithAccessToken(url, options, accessToken)
         );
       } else {
         return this._fetchWithXsrfToken(url, options);
@@ -146,7 +147,7 @@
         params.push(`access_token=${accessToken}`);
         const baseUrl = Gerrit.BaseUrlBehavior.getBaseUrl();
         const pathname = baseUrl ?
-              url.substring(url.indexOf(baseUrl) + baseUrl.length) : url;
+          url.substring(url.indexOf(baseUrl) + baseUrl.length) : url;
         if (!pathname.startsWith('/a/')) {
           url = url.replace(pathname, '/a' + pathname);
         }
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth_test.html b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth_test.html
index cfdc6ee..6c5c150 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-auth_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-auth</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -111,8 +111,8 @@
       test('getToken calls are cached', () => {
         return Promise.all([
           auth.fetch('/url-one'), auth.fetch('/url-two')]).then(() => {
-            assert.equal(getToken.callCount, 1);
-          });
+          assert.equal(getToken.callCount, 1);
+        });
       });
 
       test('getToken refreshes token', () => {
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-etag-decorator_test.html b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-etag-decorator_test.html
index 76c8c2c..623ea18 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-etag-decorator_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-etag-decorator_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-etag-decorator</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.js b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.js
index 078c332..75593e8 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.js
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface.js
@@ -39,16 +39,21 @@
   const ANONYMIZED_REVISION_BASE_URL = ANONYMIZED_CHANGE_BASE_URL +
       '/revisions/*';
 
-  Polymer({
-    is: 'gr-rest-api-interface',
-
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.PathListBehavior,
-      Gerrit.PatchSetBehavior,
-      Gerrit.RESTClientBehavior,
-    ],
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.PathListMixin
+    * @appliesMixin Gerrit.PatchSetMixin
+    * @appliesMixin Gerrit.RESTClientMixin
+    */
+  class GrRestApiInterface extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.PathListBehavior,
+    Gerrit.PatchSetBehavior,
+    Gerrit.RESTClientBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-rest-api-interface'; }
     /**
      * Fired when an server error occurs.
      *
@@ -73,43 +78,49 @@
      * @event rpc-log
      */
 
-    properties: {
-      _cache: {
-        type: Object,
-        value: new SiteBasedCache(), // Shared across instances.
-      },
-      _credentialCheck: {
-        type: Object,
-        value: {checking: false}, // Shared across instances.
-      },
-      _sharedFetchPromises: {
-        type: Object,
-        value: new FetchPromisesCache(), // Shared across instances.
-      },
-      _pendingRequests: {
-        type: Object,
-        value: {}, // Intentional to share the object across instances.
-      },
-      _etags: {
-        type: Object,
-        value: new GrEtagDecorator(), // Share across instances.
-      },
-      /**
+    constructor() {
+      super();
+      this.JSON_PREFIX = JSON_PREFIX;
+    }
+
+    static get properties() {
+      return {
+        _cache: {
+          type: Object,
+          value: new SiteBasedCache(), // Shared across instances.
+        },
+        _credentialCheck: {
+          type: Object,
+          value: {checking: false}, // Shared across instances.
+        },
+        _sharedFetchPromises: {
+          type: Object,
+          value: new FetchPromisesCache(), // Shared across instances.
+        },
+        _pendingRequests: {
+          type: Object,
+          value: {}, // Intentional to share the object across instances.
+        },
+        _etags: {
+          type: Object,
+          value: new GrEtagDecorator(), // Share across instances.
+        },
+        /**
        * Used to maintain a mapping of changeNums to project names.
        */
-      _projectLookup: {
-        type: Object,
-        value: {}, // Intentional to share the object across instances.
-      },
-      _auth: {
-        type: Object,
-        value: Gerrit.Auth, // Share across instances.
-      },
-    },
-
-    JSON_PREFIX,
+        _projectLookup: {
+          type: Object,
+          value: {}, // Intentional to share the object across instances.
+        },
+        _auth: {
+          type: Object,
+          value: Gerrit.Auth, // Share across instances.
+        },
+      };
+    }
 
     created() {
+      super.created();
       /* Polymer 1 and Polymer 2 have slightly different lifecycle.
       * Differences are not very well documented (see
       * https://github.com/Polymer/old-docs-site/issues/2322).
@@ -130,12 +141,13 @@
       //
 
       this._initRestApiHelper();
-    },
+    }
 
     ready() {
+      super.ready();
       // See comments in created()
       this._initRestApiHelper();
-    },
+    }
 
     _initRestApiHelper() {
       if (this._restApiHelper) {
@@ -146,12 +158,12 @@
         this._restApiHelper = new GrRestApiHelper(this._cache, this._auth,
             this._sharedFetchPromises, this._credentialCheck, this);
       }
-    },
+    }
 
     _fetchSharedCacheURL(req) {
       // Cache is shared across instances
       return this._restApiHelper.fetchCacheURL(req);
-    },
+    }
 
     /**
      * @param {!Object} response
@@ -159,7 +171,7 @@
      */
     getResponseObject(response) {
       return this._restApiHelper.getResponseObject(response);
-    },
+    }
 
     getConfig(noCache) {
       if (!noCache) {
@@ -173,7 +185,7 @@
         url: '/config/server/info',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getRepo(repo, opt_errFn) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -183,7 +195,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*',
       });
-    },
+    }
 
     getProjectConfig(repo, opt_errFn) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -193,7 +205,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/config',
       });
-    },
+    }
 
     getRepoAccess(repo) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -202,7 +214,7 @@
         url: '/access/?project=' + encodeURIComponent(repo),
         anonymizedUrl: '/access/?project=*',
       });
-    },
+    }
 
     getRepoDashboards(repo, opt_errFn) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -212,7 +224,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/dashboards?inherited',
       });
-    },
+    }
 
     saveRepoConfig(repo, config, opt_errFn) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -226,7 +238,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/config',
       });
-    },
+    }
 
     runRepoGC(repo, opt_errFn) {
       if (!repo) { return ''; }
@@ -240,7 +252,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/gc',
       });
-    },
+    }
 
     /**
      * @param {?Object} config
@@ -258,7 +270,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*',
       });
-    },
+    }
 
     /**
      * @param {?Object} config
@@ -274,7 +286,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/groups/*',
       });
-    },
+    }
 
     getGroupConfig(group, opt_errFn) {
       return this._restApiHelper.fetchJSON({
@@ -282,7 +294,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/groups/*/detail',
       });
-    },
+    }
 
     /**
      * @param {string} repo
@@ -302,7 +314,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/branches/*',
       });
-    },
+    }
 
     /**
      * @param {string} repo
@@ -322,7 +334,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/tags/*',
       });
-    },
+    }
 
     /**
      * @param {string} name
@@ -343,7 +355,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/branches/*',
       });
-    },
+    }
 
     /**
      * @param {string} name
@@ -364,7 +376,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/tags/*',
       });
-    },
+    }
 
     /**
      * @param {!string} groupName
@@ -378,7 +390,7 @@
       };
       return this._fetchSharedCacheURL(req)
           .then(configs => configs.hasOwnProperty(groupName));
-    },
+    }
 
     getGroupMembers(groupName, opt_errFn) {
       const encodeName = encodeURIComponent(groupName);
@@ -387,14 +399,14 @@
         errFn: opt_errFn,
         anonymizedUrl: '/groups/*/members',
       });
-    },
+    }
 
     getIncludedGroup(groupName) {
       return this._restApiHelper.fetchJSON({
         url: `/groups/${encodeURIComponent(groupName)}/groups/`,
         anonymizedUrl: '/groups/*/groups',
       });
-    },
+    }
 
     saveGroupName(groupId, name) {
       const encodeId = encodeURIComponent(groupId);
@@ -404,7 +416,7 @@
         body: {name},
         anonymizedUrl: '/groups/*/name',
       });
-    },
+    }
 
     saveGroupOwner(groupId, ownerId) {
       const encodeId = encodeURIComponent(groupId);
@@ -414,7 +426,7 @@
         body: {owner: ownerId},
         anonymizedUrl: '/groups/*/owner',
       });
-    },
+    }
 
     saveGroupDescription(groupId, description) {
       const encodeId = encodeURIComponent(groupId);
@@ -424,7 +436,7 @@
         body: {description},
         anonymizedUrl: '/groups/*/description',
       });
-    },
+    }
 
     saveGroupOptions(groupId, options) {
       const encodeId = encodeURIComponent(groupId);
@@ -434,7 +446,7 @@
         body: options,
         anonymizedUrl: '/groups/*/options',
       });
-    },
+    }
 
     getGroupAuditLog(group, opt_errFn) {
       return this._fetchSharedCacheURL({
@@ -442,7 +454,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/groups/*/log.audit',
       });
-    },
+    }
 
     saveGroupMembers(groupName, groupMembers) {
       const encodeName = encodeURIComponent(groupName);
@@ -453,7 +465,7 @@
         parseResponse: true,
         anonymizedUrl: '/groups/*/members/*',
       });
-    },
+    }
 
     saveIncludedGroup(groupName, includedGroup, opt_errFn) {
       const encodeName = encodeURIComponent(groupName);
@@ -469,7 +481,7 @@
           return this.getResponseObject(response);
         }
       });
-    },
+    }
 
     deleteGroupMembers(groupName, groupMembers) {
       const encodeName = encodeURIComponent(groupName);
@@ -479,7 +491,7 @@
         url: `/groups/${encodeName}/members/${encodeMember}`,
         anonymizedUrl: '/groups/*/members/*',
       });
-    },
+    }
 
     deleteIncludedGroup(groupName, includedGroup) {
       const encodeName = encodeURIComponent(groupName);
@@ -489,14 +501,14 @@
         url: `/groups/${encodeName}/groups/${encodeIncludedGroup}`,
         anonymizedUrl: '/groups/*/groups/*',
       });
-    },
+    }
 
     getVersion() {
       return this._fetchSharedCacheURL({
         url: '/config/server/version',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getDiffPreferences() {
       return this.getLoggedIn().then(loggedIn => {
@@ -527,7 +539,7 @@
           theme: 'DEFAULT',
         });
       });
-    },
+    }
 
     getEditPreferences() {
       return this.getLoggedIn().then(loggedIn => {
@@ -558,7 +570,7 @@
           theme: 'DEFAULT',
         });
       });
-    },
+    }
 
     /**
      * @param {?Object} prefs
@@ -578,7 +590,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {?Object} prefs
@@ -594,7 +606,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {?Object} prefs
@@ -610,7 +622,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getAccount() {
       return this._fetchSharedCacheURL({
@@ -622,7 +634,7 @@
           }
         },
       });
-    },
+    }
 
     getAvatarChangeUrl() {
       return this._fetchSharedCacheURL({
@@ -634,14 +646,14 @@
           }
         },
       });
-    },
+    }
 
     getExternalIds() {
       return this._restApiHelper.fetchJSON({
         url: '/accounts/self/external.ids',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     deleteAccountIdentity(id) {
       return this._restApiHelper.send({
@@ -651,7 +663,7 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} userId the ID of the user usch as an email address.
@@ -662,14 +674,14 @@
         url: `/accounts/${encodeURIComponent(userId)}/detail`,
         anonymizedUrl: '/accounts/*/detail',
       });
-    },
+    }
 
     getAccountEmails() {
       return this._fetchSharedCacheURL({
         url: '/accounts/self/emails',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} email
@@ -682,7 +694,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/account/self/emails/*',
       });
-    },
+    }
 
     /**
      * @param {string} email
@@ -695,7 +707,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/accounts/self/email/*',
       });
-    },
+    }
 
     /**
      * @param {string} email
@@ -724,7 +736,7 @@
           this._cache.set('/accounts/self/emails', emails);
         }
       });
-    },
+    }
 
     /**
      * @param {?Object} obj
@@ -738,7 +750,7 @@
         this._cache.set('/accounts/self/detail',
             Object.assign({}, cachedAccount, obj));
       }
-    },
+    }
 
     /**
      * @param {string} name
@@ -755,7 +767,7 @@
       };
       return this._restApiHelper.send(req)
           .then(newName => this._updateCachedAccount({name: newName}));
-    },
+    }
 
     /**
      * @param {string} username
@@ -772,7 +784,7 @@
       };
       return this._restApiHelper.send(req)
           .then(newName => this._updateCachedAccount({username: newName}));
-    },
+    }
 
     /**
      * @param {string} status
@@ -789,28 +801,28 @@
       };
       return this._restApiHelper.send(req)
           .then(newStatus => this._updateCachedAccount({status: newStatus}));
-    },
+    }
 
     getAccountStatus(userId) {
       return this._restApiHelper.fetchJSON({
         url: `/accounts/${encodeURIComponent(userId)}/status`,
         anonymizedUrl: '/accounts/*/status',
       });
-    },
+    }
 
     getAccountGroups() {
       return this._restApiHelper.fetchJSON({
         url: '/accounts/self/groups',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getAccountAgreements() {
       return this._restApiHelper.fetchJSON({
         url: '/accounts/self/agreements',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     saveAccountAgreement(name) {
       return this._restApiHelper.send({
@@ -819,7 +831,7 @@
         body: name,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string=} opt_params
@@ -835,7 +847,7 @@
         url: '/accounts/self/capabilities' + queryString,
         anonymizedUrl: '/accounts/self/capabilities?q=*',
       });
-    },
+    }
 
     getLoggedIn() {
       return this.getAccount().then(account => {
@@ -843,7 +855,7 @@
       }).catch(() => {
         return false;
       });
-    },
+    }
 
     getIsAdmin() {
       return this.getLoggedIn().then(isLoggedIn => {
@@ -855,18 +867,18 @@
       }).then(capabilities => {
         return capabilities && capabilities.administrateServer;
       });
-    },
+    }
 
     checkCredentials() {
       return this._restApiHelper.checkCredentials();
-    },
+    }
 
     getDefaultPreferences() {
       return this._fetchSharedCacheURL({
         url: '/config/server/preferences',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getPreferences() {
       return this.getLoggedIn().then(loggedIn => {
@@ -887,19 +899,19 @@
         return Promise.resolve({
           changes_per_page: 25,
           default_diff_view: this._isNarrowScreen() ?
-              DiffViewMode.UNIFIED : DiffViewMode.SIDE_BY_SIDE,
+            DiffViewMode.UNIFIED : DiffViewMode.SIDE_BY_SIDE,
           diff_view: 'SIDE_BY_SIDE',
           size_bar_in_change_table: true,
         });
       });
-    },
+    }
 
     getWatchedProjects() {
       return this._fetchSharedCacheURL({
         url: '/accounts/self/watched.projects',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} projects
@@ -914,7 +926,7 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} projects
@@ -928,11 +940,11 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     _isNarrowScreen() {
       return window.innerWidth < MAX_UNIFIED_DEFAULT_WINDOW_WIDTH_PX;
-    },
+    }
 
     /**
      * @param {number=} opt_changesPerPage
@@ -988,7 +1000,7 @@
         }
         return response;
       });
-    },
+    }
 
     /**
      * Inserts a change into _projectLookup iff it has a valid structure.
@@ -998,7 +1010,7 @@
       if (change && change.project && change._number) {
         this.setInProjectLookup(change._number, change.project);
       }
-    },
+    }
 
     /**
      * TODO (beckysiegel) this needs to be rewritten with the optional param
@@ -1012,7 +1024,7 @@
     getChangeActionURL(changeNum, opt_patchNum, endpoint) {
       return this._changeBaseURL(changeNum, opt_patchNum)
           .then(url => url + endpoint);
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1043,7 +1055,7 @@
             changeNum, optionsHex, opt_errFn, opt_cancelCondition)
             .then(GrReviewerUpdatesParser.parse);
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1059,7 +1071,7 @@
       );
       return this._getChangeDetail(changeNum, optionsHex, opt_errFn,
           opt_cancelCondition);
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1097,8 +1109,8 @@
           }
 
           const payloadPromise = response ?
-              this._restApiHelper.readResponsePayload(response) :
-              Promise.resolve(null);
+            this._restApiHelper.readResponsePayload(response) :
+            Promise.resolve(null);
 
           return payloadPromise.then(payload => {
             if (!payload) { return null; }
@@ -1109,7 +1121,7 @@
           });
         });
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1122,7 +1134,7 @@
         patchNum,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1143,7 +1155,7 @@
         params,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1161,7 +1173,7 @@
         endpoint,
         anonymizedEndpoint,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1176,7 +1188,7 @@
         patchNum,
         anonymizedEndpoint: '/files?q=*',
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1186,10 +1198,10 @@
     getChangeOrEditFiles(changeNum, patchRange) {
       if (this.patchNumEquals(patchRange.patchNum, this.EDIT_NAME)) {
         return this.getChangeEditFiles(changeNum, patchRange).then(res =>
-            res.files);
+          res.files);
       }
       return this.getChangeFiles(changeNum, patchRange);
-    },
+    }
 
     /**
      * The closure compiler doesn't realize this.specialFilePathCompare is
@@ -1201,7 +1213,7 @@
         if (!files) return;
         return Object.keys(files).sort(this.specialFilePathCompare);
       });
-    },
+    }
 
     getChangeRevisionActions(changeNum, patchNum) {
       const req = {
@@ -1219,7 +1231,7 @@
         }
         return revisionActions;
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1229,7 +1241,7 @@
     getChangeSuggestedReviewers(changeNum, inputVal, opt_errFn) {
       return this._getChangeSuggestedGroup('REVIEWER', changeNum, inputVal,
           opt_errFn);
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1239,7 +1251,7 @@
     getChangeSuggestedCCs(changeNum, inputVal, opt_errFn) {
       return this._getChangeSuggestedGroup('CC', changeNum, inputVal,
           opt_errFn);
-    },
+    }
 
     _getChangeSuggestedGroup(reviewerState, changeNum, inputVal, opt_errFn) {
       // More suggestions may obscure content underneath in the reply dialog,
@@ -1253,7 +1265,7 @@
         params,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1264,7 +1276,7 @@
         endpoint: '/in',
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     _computeFilter(filter) {
       if (filter && filter.startsWith('^')) {
@@ -1275,7 +1287,7 @@
         filter = '';
       }
       return filter;
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1287,7 +1299,7 @@
 
       return `/groups/?n=${groupsPerPage + 1}&S=${offset}` +
         this._computeFilter(filter);
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1323,15 +1335,15 @@
 
       return `/projects/?n=${reposPerPage + 1}&S=${offset}` +
         `&query=${encodedFilter}`;
-    },
+    }
 
     invalidateGroupsCache() {
       this._restApiHelper.invalidateFetchPromisesPrefix('/groups/?');
-    },
+    }
 
     invalidateReposCache() {
       this._restApiHelper.invalidateFetchPromisesPrefix('/projects/?');
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1346,7 +1358,7 @@
         url,
         anonymizedUrl: '/groups/?*',
       });
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1363,7 +1375,7 @@
         url,
         anonymizedUrl: '/projects/?*',
       });
-    },
+    }
 
     setRepoHead(repo, ref) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -1374,7 +1386,7 @@
         body: {ref},
         anonymizedUrl: '/projects/*/HEAD',
       });
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1397,7 +1409,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/branches?*',
       });
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1421,7 +1433,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/tags',
       });
-    },
+    }
 
     /**
      * @param {string} filter
@@ -1440,7 +1452,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/plugins/?all',
       });
-    },
+    }
 
     getRepoAccessRights(repoName, opt_errFn) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -1450,7 +1462,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/access',
       });
-    },
+    }
 
     setRepoAccessRights(repoName, repoInfo) {
       // TODO(kaspern): Rename rest api from /projects/ to /repos/ once backend
@@ -1461,7 +1473,7 @@
         body: repoInfo,
         anonymizedUrl: '/projects/*/access',
       });
-    },
+    }
 
     setRepoAccessRightsForReview(projectName, projectInfo) {
       return this._restApiHelper.send({
@@ -1471,7 +1483,7 @@
         parseResponse: true,
         anonymizedUrl: '/projects/*/access:review',
       });
-    },
+    }
 
     /**
      * @param {string} inputVal
@@ -1487,7 +1499,7 @@
         params,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} inputVal
@@ -1507,7 +1519,7 @@
         params,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {string} inputVal
@@ -1526,15 +1538,15 @@
         params,
         anonymizedUrl: '/accounts/?n=*',
       });
-    },
+    }
 
     addChangeReviewer(changeNum, reviewerID) {
       return this._sendChangeReviewerRequest('POST', changeNum, reviewerID);
-    },
+    }
 
     removeChangeReviewer(changeNum, reviewerID) {
       return this._sendChangeReviewerRequest('DELETE', changeNum, reviewerID);
-    },
+    }
 
     _sendChangeReviewerRequest(method, changeNum, reviewerID) {
       return this.getChangeActionURL(changeNum, null, '/reviewers')
@@ -1553,7 +1565,7 @@
 
             return this._restApiHelper.send({method, url, body});
           });
-    },
+    }
 
     getRelatedChanges(changeNum, patchNum) {
       return this._getChangeURLAndFetch({
@@ -1562,7 +1574,7 @@
         patchNum,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     getChangesSubmittedTogether(changeNum) {
       return this._getChangeURLAndFetch({
@@ -1570,7 +1582,7 @@
         endpoint: '/submitted_together?o=NON_VISIBLE_CHANGES',
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     getChangeConflicts(changeNum) {
       const options = this.listChangesOptionsToHex(
@@ -1579,14 +1591,14 @@
       );
       const params = {
         O: options,
-        q: 'status:open is:mergeable conflicts:' + changeNum,
+        q: 'status:open conflicts:' + changeNum,
       };
       return this._restApiHelper.fetchJSON({
         url: '/changes/',
         params,
         anonymizedUrl: '/changes/conflicts:*',
       });
-    },
+    }
 
     getChangeCherryPicks(project, changeID, changeNum) {
       const options = this.listChangesOptionsToHex(
@@ -1608,7 +1620,7 @@
         params,
         anonymizedUrl: '/changes/change:*',
       });
-    },
+    }
 
     getChangesWithSameTopic(topic, changeNum) {
       const options = this.listChangesOptionsToHex(
@@ -1631,7 +1643,7 @@
         params,
         anonymizedUrl: '/changes/topic:*',
       });
-    },
+    }
 
     getReviewedFiles(changeNum, patchNum) {
       return this._getChangeURLAndFetch({
@@ -1640,7 +1652,7 @@
         patchNum,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1658,7 +1670,7 @@
         errFn: opt_errFn,
         anonymizedEndpoint: '/files/*/reviewed',
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1679,7 +1691,7 @@
           errFn: opt_errFn,
         });
       });
-    },
+    }
 
     getChangeEdit(changeNum, opt_download_commands) {
       const params = opt_download_commands ? {'download-commands': true} : null;
@@ -1692,7 +1704,7 @@
           reportEndpointAsIs: true,
         });
       });
-    },
+    }
 
     /**
      * @param {string} project
@@ -1722,7 +1734,7 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1737,8 +1749,8 @@
         return res;
       };
       const promise = this.patchNumEquals(patchNum, this.EDIT_NAME) ?
-          this._getFileInChangeEdit(changeNum, path) :
-          this._getFileInRevision(changeNum, path, patchNum, suppress404s);
+        this._getFileInChangeEdit(changeNum, path) :
+        this._getFileInRevision(changeNum, path, patchNum, suppress404s);
 
       return promise.then(res => {
         if (!res.ok) { return res; }
@@ -1750,7 +1762,7 @@
           return {content, type, ok: true};
         });
       });
-    },
+    }
 
     /**
      * Gets a file in a specific change and revision.
@@ -1769,7 +1781,7 @@
         headers: {Accept: 'application/json'},
         anonymizedEndpoint: '/files/*/content',
       });
-    },
+    }
 
     /**
      * Gets a file in a change edit.
@@ -1784,7 +1796,7 @@
         headers: {Accept: 'application/json'},
         anonymizedEndpoint: '/edit/*',
       });
-    },
+    }
 
     rebaseChangeEdit(changeNum) {
       return this._getChangeURLAndSend({
@@ -1793,7 +1805,7 @@
         endpoint: '/edit:rebase',
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     deleteChangeEdit(changeNum) {
       return this._getChangeURLAndSend({
@@ -1802,7 +1814,7 @@
         endpoint: '/edit',
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     restoreFileInChangeEdit(changeNum, restore_path) {
       return this._getChangeURLAndSend({
@@ -1812,7 +1824,7 @@
         body: {restore_path},
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     renameFileInChangeEdit(changeNum, old_path, new_path) {
       return this._getChangeURLAndSend({
@@ -1822,7 +1834,7 @@
         body: {old_path, new_path},
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     deleteFileInChangeEdit(changeNum, path) {
       return this._getChangeURLAndSend({
@@ -1831,7 +1843,7 @@
         endpoint: '/edit/' + encodeURIComponent(path),
         anonymizedEndpoint: '/edit/*',
       });
-    },
+    }
 
     saveChangeEdit(changeNum, path, contents) {
       return this._getChangeURLAndSend({
@@ -1842,7 +1854,7 @@
         contentType: 'text/plain',
         anonymizedEndpoint: '/edit/*',
       });
-    },
+    }
 
     // Deprecated, prefer to use putChangeCommitMessage instead.
     saveChangeCommitMessageEdit(changeNum, message) {
@@ -1853,7 +1865,7 @@
         body: {message},
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     publishChangeEdit(changeNum) {
       return this._getChangeURLAndSend({
@@ -1862,7 +1874,7 @@
         endpoint: '/edit:publish',
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     putChangeCommitMessage(changeNum, message) {
       return this._getChangeURLAndSend({
@@ -1872,7 +1884,7 @@
         body: {message},
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     saveChangeStarred(changeNum, starred) {
       // Some servers may require the project name to be provided
@@ -1887,7 +1899,7 @@
           anonymizedUrl: '/accounts/self/starred.changes/*',
         });
       });
-    },
+    }
 
     saveChangeReviewed(changeNum, reviewed) {
       return this._getChangeURLAndSend({
@@ -1895,7 +1907,7 @@
         method: 'PUT',
         endpoint: reviewed ? '/reviewed' : '/unreviewed',
       });
-    },
+    }
 
     /**
      * Public version of the _restApiHelper.send method preserved for plugins.
@@ -1919,7 +1931,7 @@
         contentType: opt_contentType,
         headers: opt_headers,
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1961,7 +1973,7 @@
       }
 
       return this._getChangeURLAndFetch(req);
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1973,7 +1985,7 @@
     getDiffComments(changeNum, opt_basePatchNum, opt_patchNum, opt_path) {
       return this._getDiffComments(changeNum, '/comments', opt_basePatchNum,
           opt_patchNum, opt_path);
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -1985,7 +1997,7 @@
     getDiffRobotComments(changeNum, opt_basePatchNum, opt_patchNum, opt_path) {
       return this._getDiffComments(changeNum, '/robotcomments',
           opt_basePatchNum, opt_patchNum, opt_path);
-    },
+    }
 
     /**
      * If the user is logged in, fetch the user's draft diff comments. If there
@@ -2004,7 +2016,7 @@
         return this._getDiffComments(changeNum, '/drafts', opt_basePatchNum,
             opt_patchNum, opt_path);
       });
-    },
+    }
 
     _setRange(comments, comment) {
       if (comment.in_reply_to && !comment.range) {
@@ -2016,7 +2028,7 @@
         }
       }
       return comment;
-    },
+    }
 
     _setRanges(comments) {
       comments = comments || [];
@@ -2027,7 +2039,7 @@
         this._setRange(comments, comment);
       }
       return comments;
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -2100,7 +2112,7 @@
           comments,
         });
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -2110,15 +2122,15 @@
     _getDiffCommentsFetchURL(changeNum, endpoint, opt_patchNum) {
       return this._changeBaseURL(changeNum, opt_patchNum)
           .then(url => url + endpoint);
-    },
+    }
 
     saveDiffDraft(changeNum, patchNum, draft) {
       return this._sendDiffDraftRequest('PUT', changeNum, patchNum, draft);
-    },
+    }
 
     deleteDiffDraft(changeNum, patchNum, draft) {
       return this._sendDiffDraftRequest('DELETE', changeNum, patchNum, draft);
-    },
+    }
 
     /**
      * @returns {boolean} Whether there are pending diff draft sends.
@@ -2126,7 +2138,7 @@
     hasPendingDiffDrafts() {
       const promises = this._pendingRequests[Requests.SEND_DIFF_DRAFT];
       return promises && promises.length;
-    },
+    }
 
     /**
      * @returns {!Promise<undefined>} A promise that resolves when all pending
@@ -2137,7 +2149,7 @@
           .then(() => {
             this._pendingRequests[Requests.SEND_DIFF_DRAFT] = [];
           });
-    },
+    }
 
     _sendDiffDraftRequest(method, changeNum, patchNum, draft) {
       const isCreate = !draft.id && method === 'PUT';
@@ -2173,7 +2185,7 @@
       }
 
       return promise;
-    },
+    }
 
     getCommitInfo(project, commit) {
       return this._restApiHelper.fetchJSON({
@@ -2181,7 +2193,7 @@
             '/commits/' + encodeURIComponent(commit),
         anonymizedUrl: '/projects/*/comments/*',
       });
-    },
+    }
 
     _fetchB64File(url) {
       return this._restApiHelper.fetch({url: this.getBaseUrl() + url})
@@ -2195,7 +2207,7 @@
                   return {body: text, type};
                 });
           });
-    },
+    }
 
     /**
      * @param {string} changeId
@@ -2205,12 +2217,12 @@
      */
     getB64FileContents(changeId, patchNum, path, opt_parentIndex) {
       const parent = typeof opt_parentIndex === 'number' ?
-          '?parent=' + opt_parentIndex : '';
+        '?parent=' + opt_parentIndex : '';
       return this._changeBaseURL(changeId, patchNum).then(url => {
         url = `${url}/files/${encodeURIComponent(path)}/content${parent}`;
         return this._fetchB64File(url);
       });
-    },
+    }
 
     getImagesForDiff(changeNum, diff, patchRange) {
       let promiseA;
@@ -2252,7 +2264,7 @@
 
         return {baseImage, revisionImage};
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -2264,8 +2276,8 @@
       // TODO(kaspern): For full slicer migration, app should warn with a call
       // stack every time _changeBaseURL is called without a project.
       const projectPromise = opt_project ?
-          Promise.resolve(opt_project) :
-          this.getFromProjectLookup(changeNum);
+        Promise.resolve(opt_project) :
+        this.getFromProjectLookup(changeNum);
       return projectPromise.then(project => {
         let url = `/changes/${encodeURIComponent(project)}~${changeNum}`;
         if (opt_patchNum) {
@@ -2273,7 +2285,7 @@
         }
         return url;
       });
-    },
+    }
 
     /**
      * @suppress {checkTypes}
@@ -2289,7 +2301,7 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @suppress {checkTypes}
@@ -2305,7 +2317,7 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     deleteAccountHttpPassword() {
       return this._restApiHelper.send({
@@ -2313,7 +2325,7 @@
         url: '/accounts/self/password.http',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @suppress {checkTypes}
@@ -2328,14 +2340,14 @@
         parseResponse: true,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getAccountSSHKeys() {
       return this._fetchSharedCacheURL({
         url: '/accounts/self/sshkeys',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     addAccountSSHKey(key) {
       const req = {
@@ -2356,7 +2368,7 @@
             if (!obj.valid) { return Promise.reject(new Error('error')); }
             return obj;
           });
-    },
+    }
 
     deleteAccountSSHKey(id) {
       return this._restApiHelper.send({
@@ -2364,14 +2376,14 @@
         url: '/accounts/self/sshkeys/' + id,
         anonymizedUrl: '/accounts/self/sshkeys/*',
       });
-    },
+    }
 
     getAccountGPGKeys() {
       return this._restApiHelper.fetchJSON({
         url: '/accounts/self/gpgkeys',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     addAccountGPGKey(key) {
       const req = {
@@ -2391,7 +2403,7 @@
             if (!obj) { return Promise.reject(new Error('error')); }
             return obj;
           });
-    },
+    }
 
     deleteAccountGPGKey(id) {
       return this._restApiHelper.send({
@@ -2399,7 +2411,7 @@
         url: '/accounts/self/gpgkeys/' + id,
         anonymizedUrl: '/accounts/self/gpgkeys/*',
       });
-    },
+    }
 
     deleteVote(changeNum, account, label) {
       return this._getChangeURLAndSend({
@@ -2408,7 +2420,7 @@
         endpoint: `/reviewers/${account}/votes/${encodeURIComponent(label)}`,
         anonymizedEndpoint: '/reviewers/*/votes/*',
       });
-    },
+    }
 
     setDescription(changeNum, patchNum, desc) {
       return this._getChangeURLAndSend({
@@ -2418,7 +2430,7 @@
         body: {description: desc},
         reportUrlAsIs: true,
       });
-    },
+    }
 
     confirmEmail(token) {
       const req = {
@@ -2433,7 +2445,7 @@
         }
         return null;
       });
-    },
+    }
 
     getCapabilities(opt_errFn) {
       return this._restApiHelper.fetchJSON({
@@ -2441,7 +2453,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     getTopMenus(opt_errFn) {
       return this._fetchSharedCacheURL({
@@ -2449,7 +2461,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     setAssignee(changeNum, assignee) {
       return this._getChangeURLAndSend({
@@ -2459,7 +2471,7 @@
         body: {assignee},
         reportUrlAsIs: true,
       });
-    },
+    }
 
     deleteAssignee(changeNum) {
       return this._getChangeURLAndSend({
@@ -2468,14 +2480,14 @@
         endpoint: '/assignee',
         reportUrlAsIs: true,
       });
-    },
+    }
 
     probePath(path) {
       return fetch(new Request(path, {method: 'HEAD'}))
           .then(response => {
             return response.ok;
           });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -2498,7 +2510,7 @@
           return 'Change marked as Work In Progress.';
         }
       });
-    },
+    }
 
     /**
      * @param {number|string} changeNum
@@ -2514,7 +2526,7 @@
         errFn: opt_errFn,
         reportUrlAsIs: true,
       });
-    },
+    }
 
     /**
      * @suppress {checkTypes}
@@ -2531,7 +2543,7 @@
         parseResponse: true,
         anonymizedEndpoint: '/comments/*/delete',
       });
-    },
+    }
 
     /**
      * Given a changeNum, gets the change.
@@ -2550,7 +2562,7 @@
         if (!res || !res.length) { return null; }
         return res[0];
       });
-    },
+    }
 
     /**
      * @param {string|number} changeNum
@@ -2563,7 +2575,7 @@
             'One of them must be invalid.');
       }
       this._projectLookup[changeNum] = project;
-    },
+    }
 
     /**
      * Checks in _projectLookup for the changeNum. If it exists, returns the
@@ -2587,7 +2599,7 @@
         this.setInProjectLookup(changeNum, change.project);
         return change.project;
       });
-    },
+    }
 
     /**
      * Alias for _changeBaseURL.then(send).
@@ -2597,9 +2609,9 @@
      */
     _getChangeURLAndSend(req) {
       const anonymizedBaseUrl = req.patchNum ?
-          ANONYMIZED_REVISION_BASE_URL : ANONYMIZED_CHANGE_BASE_URL;
+        ANONYMIZED_REVISION_BASE_URL : ANONYMIZED_CHANGE_BASE_URL;
       const anonymizedEndpoint = req.reportEndpointAsIs ?
-          req.endpoint : req.anonymizedEndpoint;
+        req.endpoint : req.anonymizedEndpoint;
 
       return this._changeBaseURL(req.changeNum, req.patchNum).then(url => {
         return this._restApiHelper.send({
@@ -2611,10 +2623,10 @@
           headers: req.headers,
           parseResponse: req.parseResponse,
           anonymizedUrl: anonymizedEndpoint ?
-              (anonymizedBaseUrl + anonymizedEndpoint) : undefined,
+            (anonymizedBaseUrl + anonymizedEndpoint) : undefined,
         });
       });
-    },
+    }
 
     /**
      * Alias for _changeBaseURL.then(_fetchJSON).
@@ -2623,9 +2635,9 @@
      */
     _getChangeURLAndFetch(req) {
       const anonymizedEndpoint = req.reportEndpointAsIs ?
-          req.endpoint : req.anonymizedEndpoint;
+        req.endpoint : req.anonymizedEndpoint;
       const anonymizedBaseUrl = req.patchNum ?
-          ANONYMIZED_REVISION_BASE_URL : ANONYMIZED_CHANGE_BASE_URL;
+        ANONYMIZED_REVISION_BASE_URL : ANONYMIZED_CHANGE_BASE_URL;
       return this._changeBaseURL(req.changeNum, req.patchNum).then(url => {
         return this._restApiHelper.fetchJSON({
           url: url + req.endpoint,
@@ -2633,10 +2645,10 @@
           params: req.params,
           fetchOptions: req.fetchOptions,
           anonymizedUrl: anonymizedEndpoint ?
-              (anonymizedBaseUrl + anonymizedEndpoint) : undefined,
+            (anonymizedBaseUrl + anonymizedEndpoint) : undefined,
         });
       });
-    },
+    }
 
     /**
      * Execute a change action or revision action on a change.
@@ -2658,7 +2670,7 @@
         body: opt_payload,
         errFn: opt_errFn,
       });
-    },
+    }
 
     /**
      * Get blame information for the given diff.
@@ -2678,7 +2690,7 @@
         params: opt_base ? {base: 't'} : undefined,
         anonymizedEndpoint: '/files/*/blame',
       });
-    },
+    }
 
     /**
      * Modify the given create draft request promise so that it fails and throws
@@ -2707,7 +2719,7 @@
         }
         return result;
       });
-    },
+    }
 
     /**
      * Fetch a project dashboard definition.
@@ -2726,7 +2738,7 @@
         errFn: opt_errFn,
         anonymizedUrl: '/projects/*/dashboards/*',
       });
-    },
+    }
 
     /**
      * @param {string} filter
@@ -2742,7 +2754,7 @@
         url: `/Documentation/?q=${encodedFilter}`,
         anonymizedUrl: '/Documentation/?*',
       });
-    },
+    }
 
     getMergeable(changeNum) {
       return this._getChangeURLAndFetch({
@@ -2751,7 +2763,7 @@
         parseResponse: true,
         reportEndpointAsIs: true,
       });
-    },
+    }
 
     deleteDraftComments(query) {
       return this._restApiHelper.send({
@@ -2759,6 +2771,8 @@
         url: '/accounts/self/drafts:delete',
         body: {query},
       });
-    },
-  });
+    }
+  }
+
+  customElements.define(GrRestApiInterface.is, GrRestApiInterface);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.html b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.html
index ea71522..a598d0d 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-rest-api-interface</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -351,7 +351,6 @@
       });
     });
 
-
     test('server error', done => {
       const getResponseObjectStub = sandbox.stub(element, 'getResponseObject');
       window.fetch.returns(Promise.resolve({ok: false}));
@@ -691,7 +690,7 @@
 
     test('setAccountStatus', () => {
       const sendStub = sandbox.stub(element._restApiHelper, 'send')
-        .returns(Promise.resolve('OOO'));
+          .returns(Promise.resolve('OOO'));
       element._cache.set('/accounts/self/detail', {});
       return element.setAccountStatus('OOO').then(() => {
         assert.isTrue(sendStub.calledOnce);
@@ -702,7 +701,7 @@
             {status: 'OOO'});
         assert.deepEqual(element._restApiHelper
             ._cache.get('/accounts/self/detail'),
-           {status: 'OOO'});
+        {status: 'OOO'});
       });
     });
 
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper.js b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper.js
index 5cea96b..c9cdfb4 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper.js
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper.js
@@ -147,7 +147,7 @@
      */
     _logCall(req, startTime, status) {
       const method = (req.fetchOptions && req.fetchOptions.method) ?
-          req.fetchOptions.method : 'GET';
+        req.fetchOptions.method : 'GET';
       const endTime = Date.now();
       const elapsed = (endTime - startTime);
       const startAt = new Date(startTime);
@@ -339,7 +339,7 @@
         options.headers.set(
             'Content-Type', req.contentType || 'application/json');
         options.body = typeof req.body === 'string' ?
-            req.body : JSON.stringify(req.body);
+          req.body : JSON.stringify(req.body);
       }
       if (req.headers) {
         if (!options.headers) { options.headers = new Headers(); }
@@ -349,7 +349,7 @@
         }
       }
       const url = req.url.startsWith('http') ?
-          req.url : this.getBaseUrl() + req.url;
+        req.url : this.getBaseUrl() + req.url;
       const fetchReq = {
         url,
         fetchOptions: options,
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper_test.html b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper_test.html
index 4eaf1bc..446cfc8 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-apis/gr-rest-api-helper_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-rest-api-helper</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser.js b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser.js
index e14b955..601f7d9 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser.js
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser.js
@@ -203,7 +203,7 @@
     messages.forEach((message, index) => {
       const messageDate = util.parseDate(message.date).getTime();
       const nextMessageDate = index === messages.length - 1 ? null :
-          util.parseDate(messages[index + 1].date).getTime();
+        util.parseDate(messages[index + 1].date).getTime();
       for (const update of updates) {
         const date = util.parseDate(update.date).getTime();
         if (date >= messageDate
@@ -211,7 +211,7 @@
           const timestamp = util.parseDate(update.date).getTime() -
               GrReviewerUpdatesParser.MESSAGE_REVIEWERS_THRESHOLD_MILLIS;
           update.date = new Date(timestamp)
-            .toISOString().replace('T', ' ').replace('Z', '000000');
+              .toISOString().replace('T', ' ').replace('Z', '000000');
         }
         if (nextMessageDate && date > nextMessageDate) {
           break;
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser_test.html b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser_test.html
index fdf79af..ad3e4ca 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-reviewer-updates-parser_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reviewer-updates-parser</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-select/gr-select.js b/polygerrit-ui/app/elements/shared/gr-select/gr-select.js
index 05267ba..152834f 100644
--- a/polygerrit-ui/app/elements/shared/gr-select/gr-select.js
+++ b/polygerrit-ui/app/elements/shared/gr-select/gr-select.js
@@ -17,29 +17,29 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-select',
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    */
+  class GrSelect extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-select'; }
 
-    properties: {
-      bindValue: {
-        type: String,
-        notify: true,
-        observer: '_updateValue',
-      },
-    },
-
-    behaviors: [
-      Gerrit.FireBehavior,
-    ],
-
-    listeners: {
-      'change': '_valueChanged',
-      'dom-change': '_updateValue',
-    },
+    static get properties() {
+      return {
+        bindValue: {
+          type: String,
+          notify: true,
+          observer: '_updateValue',
+        },
+      };
+    }
 
     get nativeSelect() {
       return this.$$('select');
-    },
+    }
 
     _updateValue() {
       // It's possible to have a value of 0.
@@ -53,21 +53,32 @@
           this.nativeSelect.value = this.bindValue;
         }, 1);
       }
-    },
+    }
 
     _valueChanged() {
       this.bindValue = this.nativeSelect.value;
-    },
+    }
 
     focus() {
       this.nativeSelect.focus();
-    },
+    }
+
+    created() {
+      super.created();
+      this.addEventListener('change',
+          () => this._valueChanged());
+      this.addEventListener('dom-change',
+          () => this._updateValue());
+    }
 
     ready() {
+      super.ready();
       // If not set via the property, set bind-value to the element value.
       if (this.bindValue == undefined && this.nativeSelect.options.length > 0) {
         this.bindValue = this.nativeSelect.value;
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrSelect.is, GrSelect);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-select/gr-select_test.html b/polygerrit-ui/app/elements/shared/gr-select/gr-select_test.html
index b3abe5f..cae61056 100644
--- a/polygerrit-ui/app/elements/shared/gr-select/gr-select_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-select/gr-select_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-select</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command.js b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command.js
index 2c546cc..9456991 100644
--- a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command.js
+++ b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command.js
@@ -17,16 +17,22 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-shell-command',
+  class GrShellCommand extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-shell-command'; }
 
-    properties: {
-      command: String,
-      label: String,
-    },
+    static get properties() {
+      return {
+        command: String,
+        label: String,
+      };
+    }
 
     focusOnCopy() {
       this.$$('gr-copy-clipboard').focusOnCopy();
-    },
-  });
+    }
+  }
+
+  customElements.define(GrShellCommand.is, GrShellCommand);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_test.html b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_test.html
index 3f2f8ba..a4bdf58 100644
--- a/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-shell-command/gr-shell-command_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-shell-command</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-storage/gr-storage.js b/polygerrit-ui/app/elements/shared/gr-storage/gr-storage.js
index 9ae77d9..7950e51 100644
--- a/polygerrit-ui/app/elements/shared/gr-storage/gr-storage.js
+++ b/polygerrit-ui/app/elements/shared/gr-storage/gr-storage.js
@@ -28,69 +28,73 @@
     'editablecontent:',
   ];
 
-  Polymer({
-    is: 'gr-storage',
+  class GrStorage extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-storage'; }
 
-    properties: {
-      _lastCleanup: Number,
-      /** @type {?Storage} */
-      _storage: {
-        type: Object,
-        value() {
-          return window.localStorage;
+    static get properties() {
+      return {
+        _lastCleanup: Number,
+        /** @type {?Storage} */
+        _storage: {
+          type: Object,
+          value() {
+            return window.localStorage;
+          },
         },
-      },
-      _exceededQuota: {
-        type: Boolean,
-        value: false,
-      },
-    },
+        _exceededQuota: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
 
     getDraftComment(location) {
       this._cleanupItems();
       return this._getObject(this._getDraftKey(location));
-    },
+    }
 
     setDraftComment(location, message) {
       const key = this._getDraftKey(location);
       this._setObject(key, {message, updated: Date.now()});
-    },
+    }
 
     eraseDraftComment(location) {
       const key = this._getDraftKey(location);
       this._storage.removeItem(key);
-    },
+    }
 
     getEditableContentItem(key) {
       this._cleanupItems();
       return this._getObject(this._getEditableContentKey(key));
-    },
+    }
 
     setEditableContentItem(key, message) {
       this._setObject(this._getEditableContentKey(key),
           {message, updated: Date.now()});
-    },
+    }
 
     eraseEditableContentItem(key) {
       this._storage.removeItem(this._getEditableContentKey(key));
-    },
+    }
 
     _getDraftKey(location) {
       const range = location.range ?
-          `${location.range.start_line}-${location.range.start_character}` +
+        `${location.range.start_line}-${location.range.start_character}` +
               `-${location.range.end_character}-${location.range.end_line}` :
-          null;
+        null;
       let key = ['draft', location.changeNum, location.patchNum, location.path,
         location.line || ''].join(':');
       if (range) {
         key = key + ':' + range;
       }
       return key;
-    },
+    }
 
     _getEditableContentKey(key) {
       return `editablecontent:${key}`;
-    },
+    }
 
     _cleanupItems() {
       // Throttle cleanup to the throttle interval.
@@ -113,13 +117,13 @@
           }
         }
       }
-    },
+    }
 
     _getObject(key) {
       const serial = this._storage.getItem(key);
       if (!serial) { return null; }
       return JSON.parse(serial);
-    },
+    }
 
     _setObject(key, obj) {
       if (this._exceededQuota) { return; }
@@ -136,6 +140,8 @@
           throw exc;
         }
       }
-    },
-  });
+    }
+  }
+
+  customElements.define(GrStorage.is, GrStorage);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-storage/gr-storage_test.html b/polygerrit-ui/app/elements/shared/gr-storage/gr-storage_test.html
index 0482584..5cd4d3e 100644
--- a/polygerrit-ui/app/elements/shared/gr-storage/gr-storage_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-storage/gr-storage_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-storage</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea.js b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea.js
index 4c4b038..5011067 100644
--- a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea.js
+++ b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea.js
@@ -52,73 +52,81 @@
     {value: '😜', match: 'winking tongue ;)'},
   ];
 
-  Polymer({
-    is: 'gr-textarea',
-
+  /**
+    * @appliesMixin Gerrit.FireMixin
+    * @appliesMixin Gerrit.KeyboardShortcutMixin
+    */
+  class GrTextarea extends Polymer.mixinBehaviors( [
+    Gerrit.FireBehavior,
+    Gerrit.KeyboardShortcutBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-textarea'; }
     /**
      * @event bind-value-changed
      */
 
-    properties: {
-      autocomplete: Boolean,
-      disabled: Boolean,
-      rows: Number,
-      maxRows: Number,
-      placeholder: String,
-      text: {
-        type: String,
-        notify: true,
-        observer: '_handleTextChanged',
-      },
-      hideBorder: {
-        type: Boolean,
-        value: false,
-      },
-      /** Text input should be rendered in monspace font.  */
-      monospace: {
-        type: Boolean,
-        value: false,
-      },
-      /** Text input should be rendered in code font, which is smaller than the
+    static get properties() {
+      return {
+        autocomplete: Boolean,
+        disabled: Boolean,
+        rows: Number,
+        maxRows: Number,
+        placeholder: String,
+        text: {
+          type: String,
+          notify: true,
+          observer: '_handleTextChanged',
+        },
+        hideBorder: {
+          type: Boolean,
+          value: false,
+        },
+        /** Text input should be rendered in monspace font.  */
+        monospace: {
+          type: Boolean,
+          value: false,
+        },
+        /** Text input should be rendered in code font, which is smaller than the
           standard monospace font. */
-      code: {
-        type: Boolean,
-        value: false,
-      },
-      /** @type(?number) */
-      _colonIndex: Number,
-      _currentSearchString: {
-        type: String,
-        observer: '_determineSuggestions',
-      },
-      _hideAutocomplete: {
-        type: Boolean,
-        value: true,
-      },
-      _index: Number,
-      _suggestions: Array,
-      // Offset makes dropdown appear below text.
-      _verticalOffset: {
-        type: Number,
-        value: 20,
-        readOnly: true,
-      },
-    },
+        code: {
+          type: Boolean,
+          value: false,
+        },
+        /** @type(?number) */
+        _colonIndex: Number,
+        _currentSearchString: {
+          type: String,
+          observer: '_determineSuggestions',
+        },
+        _hideAutocomplete: {
+          type: Boolean,
+          value: true,
+        },
+        _index: Number,
+        _suggestions: Array,
+        // Offset makes dropdown appear below text.
+        _verticalOffset: {
+          type: Number,
+          value: 20,
+          readOnly: true,
+        },
+      };
+    }
 
-    behaviors: [
-      Gerrit.FireBehavior,
-      Gerrit.KeyboardShortcutBehavior,
-    ],
-
-    keyBindings: {
-      esc: '_handleEscKey',
-      tab: '_handleEnterByKey',
-      enter: '_handleEnterByKey',
-      up: '_handleUpKey',
-      down: '_handleDownKey',
-    },
+    get keyBindings() {
+      return {
+        esc: '_handleEscKey',
+        tab: '_handleEnterByKey',
+        enter: '_handleEnterByKey',
+        up: '_handleUpKey',
+        down: '_handleDownKey',
+      };
+    }
 
     ready() {
+      super.ready();
       if (this.monospace) {
         this.classList.add('monospace');
       }
@@ -128,15 +136,15 @@
       if (this.hideBorder) {
         this.$.textarea.classList.add('noBorder');
       }
-    },
+    }
 
     closeDropdown() {
       return this.$.emojiSuggestions.close();
-    },
+    }
 
     getNativeTextarea() {
       return this.$.textarea.textarea;
-    },
+    }
 
     putCursorAtEnd() {
       const textarea = this.getNativeTextarea();
@@ -146,14 +154,14 @@
       this.async(() => {
         textarea.focus();
       });
-    },
+    }
 
     _handleEscKey(e) {
       if (this._hideAutocomplete) { return; }
       e.preventDefault();
       e.stopPropagation();
       this._resetEmojiDropdown();
-    },
+    }
 
     _handleUpKey(e) {
       if (this._hideAutocomplete) { return; }
@@ -162,7 +170,7 @@
       this.$.emojiSuggestions.cursorUp();
       this.$.textarea.textarea.focus();
       this.disableEnterKeyForSelectingEmoji = false;
-    },
+    }
 
     _handleDownKey(e) {
       if (this._hideAutocomplete) { return; }
@@ -171,7 +179,7 @@
       this.$.emojiSuggestions.cursorDown();
       this.$.textarea.textarea.focus();
       this.disableEnterKeyForSelectingEmoji = false;
-    },
+    }
 
     _handleEnterByKey(e) {
       if (this._hideAutocomplete || this.disableEnterKeyForSelectingEmoji) {
@@ -180,11 +188,11 @@
       e.preventDefault();
       e.stopPropagation();
       this._setEmoji(this.$.emojiSuggestions.getCurrentText());
-    },
+    }
 
     _handleEmojiSelect(e) {
       this._setEmoji(e.detail.selected.dataset.value);
-    },
+    }
 
     _setEmoji(text) {
       const colonIndex = this._colonIndex;
@@ -193,12 +201,13 @@
       this.$.textarea.selectionEnd = colonIndex + 1;
       this.$.reporting.reportInteraction('select-emoji');
       this._resetEmojiDropdown();
-    },
+    }
 
     _getText(value) {
       return this.text.substr(0, this._colonIndex || 0) +
           value + this.text.substr(this.$.textarea.selectionStart);
-    },
+    }
+
     /**
      * Uses a hidden element with the same width and styling of the textarea and
      * the text up until the point of interest. Then caratSpan element is added
@@ -214,17 +223,17 @@
       this.$.hiddenText.appendChild(caratSpan);
       this.$.emojiSuggestions.positionTarget = caratSpan;
       this._openEmojiDropdown();
-    },
+    }
 
     _getFontSize() {
       const fontSizePx = getComputedStyle(this).fontSize || '12px';
       return parseInt(fontSizePx.substr(0, fontSizePx.length - 2),
           10);
-    },
+    }
 
     _getScrollTop() {
       return document.body.scrollTop;
-    },
+    }
 
     /**
      * _handleKeydown used for key handling in the this.$.textarea AND all child
@@ -271,12 +280,12 @@
         this._updateCaratPosition();
       }
       this.$.textarea.textarea.focus();
-    },
+    }
 
     _openEmojiDropdown() {
       this.$.emojiSuggestions.open();
       this.$.reporting.reportInteraction('open-emoji-dropdown');
-    },
+    }
 
     _formatSuggestions(matchedSuggestions) {
       const suggestions = [];
@@ -286,7 +295,7 @@
         suggestions.push(suggestion);
       }
       this.set('_suggestions', suggestions);
-    },
+    }
 
     _determineSuggestions(emojiText) {
       if (!emojiText.length) {
@@ -299,7 +308,7 @@
         this._formatSuggestions(matches);
         this.disableEnterKeyForSelectingEmoji = false;
       }
-    },
+    }
 
     _resetEmojiDropdown() {
       // hide and reset the autocomplete dropdown.
@@ -309,11 +318,13 @@
       this.closeDropdown();
       this._colonIndex = null;
       this.$.textarea.textarea.focus();
-    },
+    }
 
     _handleTextChanged(text) {
       this.dispatchEvent(
           new CustomEvent('value-changed', {detail: {value: text}}));
-    },
-  });
+    }
+  }
+
+  customElements.define(GrTextarea.is, GrTextarea);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_test.html b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_test.html
index ae1de02..699deab 100644
--- a/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-textarea/gr-textarea_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-textarea</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -209,17 +209,17 @@
       assert.isTrue(formatSpy.lastCall.calledWithExactly(
           [{dataValue: '😂', value: '😂', match: 'tears :\')',
             text: '😂 tears :\')'},
-            {dataValue: '😢', value: '😢', match: 'tear', text: '😢 tear'},
+          {dataValue: '😢', value: '😢', match: 'tear', text: '😢 tear'},
           ]));
     });
 
     test('_formatSuggestions', () => {
       const matchedSuggestions = [{value: '😢', match: 'tear'},
-          {value: '😂', match: 'tears'}];
+        {value: '😂', match: 'tears'}];
       element._formatSuggestions(matchedSuggestions);
       assert.deepEqual(
           [{value: '😢', dataValue: '😢', match: 'tear', text: '😢 tear'},
-          {value: '😂', dataValue: '😂', match: 'tears', text: '😂 tears'}],
+            {value: '😂', dataValue: '😂', match: 'tears', text: '😂 tears'}],
           element._suggestions);
     });
 
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content.js b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content.js
index c5de8f4..3559949 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content.js
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content.js
@@ -17,31 +17,38 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-tooltip-content',
+  /**
+    * @appliesMixin Gerrit.TooltipMixin
+    */
+  class GrTooltipContent extends Polymer.mixinBehaviors( [
+    Gerrit.TooltipBehavior,
+  ], Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element))) {
+    static get is() { return 'gr-tooltip-content'; }
 
-    properties: {
-      title: {
-        type: String,
-        reflectToAttribute: true,
-      },
-      maxWidth: {
-        type: String,
-        reflectToAttribute: true,
-      },
-      positionBelow: {
-        type: Boolean,
-        valye: false,
-        reflectToAttribute: true,
-      },
-      showIcon: {
-        type: Boolean,
-        value: false,
-      },
-    },
+    static get properties() {
+      return {
+        title: {
+          type: String,
+          reflectToAttribute: true,
+        },
+        maxWidth: {
+          type: String,
+          reflectToAttribute: true,
+        },
+        positionBelow: {
+          type: Boolean,
+          valye: false,
+          reflectToAttribute: true,
+        },
+        showIcon: {
+          type: Boolean,
+          value: false,
+        },
+      };
+    }
+  }
 
-    behaviors: [
-      Gerrit.TooltipBehavior,
-    ],
-  });
+  customElements.define(GrTooltipContent.is, GrTooltipContent);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_test.html b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_test.html
index f9350c6..4276195 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip-content/gr-tooltip-content_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-storage</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip.js b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip.js
index fb87b558..170a442 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip.js
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip.js
@@ -17,23 +17,29 @@
 (function() {
   'use strict';
 
-  Polymer({
-    is: 'gr-tooltip',
+  class GrTooltip extends Polymer.GestureEventListeners(
+      Polymer.LegacyElementMixin(
+          Polymer.Element)) {
+    static get is() { return 'gr-tooltip'; }
 
-    properties: {
-      text: String,
-      maxWidth: {
-        type: String,
-        observer: '_updateWidth',
-      },
-      positionBelow: {
-        type: Boolean,
-        reflectToAttribute: true,
-      },
-    },
+    static get properties() {
+      return {
+        text: String,
+        maxWidth: {
+          type: String,
+          observer: '_updateWidth',
+        },
+        positionBelow: {
+          type: Boolean,
+          reflectToAttribute: true,
+        },
+      };
+    }
 
     _updateWidth(maxWidth) {
       this.updateStyles({'--tooltip-max-width': maxWidth});
-    },
-  });
+    }
+  }
+
+  customElements.define(GrTooltip.is, GrTooltip);
 })();
diff --git a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_test.html b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_test.html
index f59f6e1..95f3922 100644
--- a/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_test.html
+++ b/polygerrit-ui/app/elements/shared/gr-tooltip/gr-tooltip_test.html
@@ -17,7 +17,7 @@
 -->
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-storage</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/elements/shared/revision-info/revision-info.html b/polygerrit-ui/app/elements/shared/revision-info/revision-info.html
index fca8ae1..75b8ac3 100644
--- a/polygerrit-ui/app/elements/shared/revision-info/revision-info.html
+++ b/polygerrit-ui/app/elements/shared/revision-info/revision-info.html
@@ -74,7 +74,7 @@
      */
     RevisionInfo.prototype.getParentId = function(patchNum, parentIndex) {
       const rev = Object.values(this._change.revisions).find(rev =>
-          Gerrit.PatchSetBehavior.patchNumEquals(rev._number, patchNum));
+        Gerrit.PatchSetBehavior.patchNumEquals(rev._number, patchNum));
       return rev.commit.parents[parentIndex].commit;
     };
 
diff --git a/polygerrit-ui/app/elements/shared/revision-info/revision-info_test.html b/polygerrit-ui/app/elements/shared/revision-info/revision-info_test.html
index 7e5810b..187ce35 100644
--- a/polygerrit-ui/app/elements/shared/revision-info/revision-info_test.html
+++ b/polygerrit-ui/app/elements/shared/revision-info/revision-info_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>revision-info</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/embed/embed.html b/polygerrit-ui/app/embed/embed.html
deleted file mode 100644
index 64e0137..0000000
--- a/polygerrit-ui/app/embed/embed.html
+++ /dev/null
@@ -1,27 +0,0 @@
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-<script>
-  window.Gerrit = window.Gerrit || {};
-</script>
-<link rel="import" href="/bower_components/polymer/polymer.html">
-<link rel="import" href="../elements/change/gr-change-view/gr-change-view.html">
-<link rel="import" href="../elements/core/gr-search-bar/gr-search-bar.html">
-<link rel="import" href="../elements/diff/gr-diff-view/gr-diff-view.html">
-<link rel="import" href="../elements/change-list/gr-change-list-view/gr-change-list-view.html">
-<link rel="import" href="../elements/change-list/gr-dashboard-view/gr-dashboard-view.html">
-<link rel="import" href="../elements/change-list/gr-embed-dashboard/gr-embed-dashboard.html">
-<link rel="import" href="../styles/themes/app-theme.html">
diff --git a/polygerrit-ui/app/embed/embed_test.html b/polygerrit-ui/app/embed/embed_test.html
deleted file mode 100644
index 1e3f5d7..0000000
--- a/polygerrit-ui/app/embed/embed_test.html
+++ /dev/null
@@ -1,98 +0,0 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<title>embed_test</title>
-<script src="/test/common-test-setup.js"></script>
-<script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
-
-<script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/bower_components/web-component-tester/browser.js"></script>
-<link rel="import" href="embed.html"/>
-
-<script>void(0);</script>
-
-<test-fixture id="change-view">
-  <template>
-    <gr-change-view></gr-change-view>
-  </template>
-</test-fixture>
-
-<test-fixture id="diff-view">
-  <template>
-    <gr-diff-view></gr-diff-view>
-  </template>
-</test-fixture>
-
-<test-fixture id="dashboard-view">
-  <template>
-    <gr-dashboard-view></gr-dashboard-view>
-  </template>
-</test-fixture>
-
-<test-fixture id="change-list-view">
-  <template>
-    <gr-change-list-view></gr-change-list-view>
-  </template>
-</test-fixture>
-
-<test-fixture id="change-list">
-  <template>
-    <gr-change-list></gr-change-list>
-  </template>
-</test-fixture>
-
-<test-fixture id="search-bar">
-  <template>
-    <gr-search-bar></gr-search-bar>
-  </template>
-</test-fixture>
-
-<script>
-  suite('embed test', () => {
-    test('gr-change-view is embedded', () => {
-      const element = fixture('change-view');
-      assert.equal(element.is, 'gr-change-view');
-    });
-
-    test('diff-view is embedded', () => {
-      const element = fixture('diff-view');
-      assert.equal(element.is, 'gr-diff-view');
-    });
-
-    test('dashboard-view is embedded', () => {
-      const element = fixture('dashboard-view');
-      assert.equal(element.is, 'gr-dashboard-view');
-    });
-
-    test('change-list-view is embedded', () => {
-      const element = fixture('change-list-view');
-      assert.equal(element.is, 'gr-change-list-view');
-    });
-
-    test('change-list is embedded', () => {
-      const element = fixture('change-list');
-      assert.equal(element.is, 'gr-change-list');
-    });
-
-    test('search-bar is embedded', () => {
-      const element = fixture('search-bar');
-      assert.equal(element.is, 'gr-search-bar');
-    });
-  });
-</script>
diff --git a/polygerrit-ui/app/embed/test.html b/polygerrit-ui/app/embed/test.html
deleted file mode 100644
index 955eaee..0000000
--- a/polygerrit-ui/app/embed/test.html
+++ /dev/null
@@ -1,26 +0,0 @@
-<!DOCTYPE html>
-<!--
-@license
-Copyright (C) 2017 The Android Open Source Project
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
--->
-
-<meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
-<title>Embed Test Runner</title>
-<meta charset="utf-8">
-<script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
-<script src="/bower_components/web-component-tester/browser.js"></script>
-<script>
-  WCT.loadSuites(['../embed/embed_test.html']);
-</script>
diff --git a/polygerrit-ui/app/embed_test.sh b/polygerrit-ui/app/embed_test.sh
deleted file mode 100755
index 0d8f58f..0000000
--- a/polygerrit-ui/app/embed_test.sh
+++ /dev/null
@@ -1,69 +0,0 @@
-#!/bin/sh
-
-set -ex
-
-t=$(mktemp -d || mktemp -d -t wct-XXXXXXXXXX)
-components=$TEST_SRCDIR/gerrit/polygerrit-ui/app/test_components.zip
-code=$TEST_SRCDIR/gerrit/polygerrit-ui/app/pg_code.zip
-
-echo $t
-unzip -qd $t $components
-unzip -qd $t $code
-# Purge test/ directory contents coming from pg_code.zip.
-rm -rf $t/test
-mkdir -p $t/test
-cp $TEST_SRCDIR/gerrit/polygerrit-ui/app/embed/test.html $t/test/
-
-if [ "${WCT_HEADLESS_MODE:-0}" != "0" ]; then
-    CHROME_OPTIONS=[\'start-maximized\',\'headless\',\'disable-gpu\',\'no-sandbox\']
-    FIREFOX_OPTIONS=[\'-headless\']
-else
-    CHROME_OPTIONS=[\'start-maximized\']
-    FIREFOX_OPTIONS=[\'\']
-fi
-
-# For some reason wct tries to install selenium into its node_modules
-# directory on first run. If you've installed into /usr/local and
-# aren't running wct as root, you're screwed. Turning this option off
-# through skipSeleniumInstall seems to still work, so there's that.
-
-# Sauce tests are disabled by default in order to run local tests
-# only.  Run it with (saucelabs.com account required; free for open
-# source): WCT_ARGS='--plugin sauce' ./polygerrit-ui/app/embed_test.sh
-
-cat <<EOF > $t/wct.conf.js
-module.exports = {
-      'suites': ['test'],
-      'webserver': {
-        'pathMappings': [
-          {'/components/bower_components': 'bower_components'}
-        ]
-      },
-      'plugins': {
-        'local': {
-          'skipSeleniumInstall': true,
-          'browserOptions': {
-            'chrome': ${CHROME_OPTIONS},
-            'firefox': ${FIREFOX_OPTIONS}
-          }
-        },
-        'sauce': {
-          'disabled': true,
-          'browsers': [
-            'OS X 10.12/chrome',
-            'Windows 10/chrome',
-            'Linux/firefox',
-            'OS X 10.12/safari',
-            'Windows 10/microsoftedge'
-          ]
-        }
-      }
-    };
-EOF
-
-export PATH="$(dirname $NPM):$PATH"
-
-cd $t
-test -n "${WCT}"
-
-${WCT} ${WCT_ARGS}
diff --git a/polygerrit-ui/app/polylint_test.sh b/polygerrit-ui/app/polylint_test.sh
index f6880a1..98cf06f 100755
--- a/polygerrit-ui/app/polylint_test.sh
+++ b/polygerrit-ui/app/polylint_test.sh
@@ -8,13 +8,24 @@
     exit 1
 fi
 
-npx_bin=$(which npx)
-if [[ -z "$npx_bin" ]]; then
-    echo "NPX must be on the path."
-    echo "> npm i -g npx"
+node_bin=$(which node)
+if [[ -z "$node_bin" ]]; then
+    echo "node must be on the path."
+    exit 1
+fi
+
+polymer_bin=$(which polymer)
+if [[ -z "$polymer_bin" ]]; then
+  polymer_bin=$(abs_path ./node_modules/polymer-cli/bin/polymer.js);
+fi
+if [[ -z "$polymer_bin" ]]; then
+    echo "polymer must be set or polymer-cli locally installed (npm install polymer-cli)."
     exit 1
 fi
 
 unzip -o polygerrit-ui/polygerrit_components.bower_components.zip -d polygerrit-ui/app
 
-npx polylint --root polygerrit-ui/app --input elements/gr-app.html --b 'bower_components' --verbose
+#Can't use --root with polymer.json - see https://github.com/Polymer/tools/issues/2616
+#Change current directory to the root folder
+cd polygerrit-ui/app
+$polymer_bin lint --component-dir 'bower_components' --verbose
diff --git a/polygerrit-ui/app/polymer.json b/polygerrit-ui/app/polymer.json
new file mode 100644
index 0000000..411c969
--- /dev/null
+++ b/polygerrit-ui/app/polymer.json
@@ -0,0 +1,14 @@
+{
+  "entrypoint": "elements/gr-app.html",
+  "sources": [
+    "behaviors/**/*",
+    "elements/**/*",
+    "scripts/**/*",
+    "styles/*",
+    "types/**/*"
+  ],
+  "lint": {
+    "rules": ["polymer-2"],
+    "ignoreWarnings": ["deprecated-dom-call"]
+  }
+}
diff --git a/polygerrit-ui/app/run_test.sh b/polygerrit-ui/app/run_test.sh
index e9be18d..76a4fa1 100755
--- a/polygerrit-ui/app/run_test.sh
+++ b/polygerrit-ui/app/run_test.sh
@@ -48,5 +48,4 @@
       --test_env="DISPLAY=${DISPLAY}" \
       --test_env="WCT_HEADLESS_MODE=${WCT_HEADLESS_MODE}" \
       "$@" \
-      //polygerrit-ui/app:embed_test \
       //polygerrit-ui/app:wct_test
diff --git a/polygerrit-ui/app/samples/coverage-plugin.html b/polygerrit-ui/app/samples/coverage-plugin.html
index f5f9c6e..fa44a47 100644
--- a/polygerrit-ui/app/samples/coverage-plugin.html
+++ b/polygerrit-ui/app/samples/coverage-plugin.html
@@ -1,6 +1,5 @@
 <dom-module id="coverage-plugin">
   <script>
-
     function populateWithDummyData(coverageData) {
       coverageData['NewFile'] = {
         linesMissingCoverage: [1, 2, 3],
@@ -39,16 +38,16 @@
 
       annotationApi.addLayer(context => {
         if (Object.keys(coverageData).length === 0) {
-           // Coverage data is not ready yet.
+          // Coverage data is not ready yet.
           return;
         }
         const path = context.path;
         const line = context.line;
-          // Highlight lines missing coverage with this background color if
-          // coverage should be displayed, else do nothing.
+        // Highlight lines missing coverage with this background color if
+        // coverage should be displayed, else do nothing.
         const annotationStyle = displayCoverage
-                         ? coverageStyle
-                         : emptyStyle;
+          ? coverageStyle
+          : emptyStyle;
         if (coverageData[path] &&
               coverageData[path].changeNum === context.changeNum &&
               coverageData[path].patchNum === context.patchNum) {
@@ -61,6 +60,8 @@
       }).enableToggleCheckbox('Display Coverage', checkbox => {
         // Checkbox is attached so now add the notifier that will be controlled
         // by the checkbox.
+        // Checkbox will only be added to the file diff page, in the top right
+        // section near the "Diff view".
         annotationApi.addNotifier(notifyFunc => {
           new Promise(resolve => setTimeout(resolve, 3000)).then(() => {
             populateWithDummyData(coverageData);
diff --git a/polygerrit-ui/app/scripts/gr-display-name-utils/gr-display-name-utils_test.html b/polygerrit-ui/app/scripts/gr-display-name-utils/gr-display-name-utils_test.html
index 25ca4c5..a35e034 100644
--- a/polygerrit-ui/app/scripts/gr-display-name-utils/gr-display-name-utils_test.html
+++ b/polygerrit-ui/app/scripts/gr-display-name-utils/gr-display-name-utils_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-display-name-utils</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -35,7 +35,6 @@
       },
     };
 
-
     test('getUserName name only', () => {
       const account = {
         name: 'test-name',
diff --git a/polygerrit-ui/app/scripts/gr-email-suggestions-provider/gr-email-suggestions-provider_test.html b/polygerrit-ui/app/scripts/gr-email-suggestions-provider/gr-email-suggestions-provider_test.html
index fb6b5d4..ac32efa 100644
--- a/polygerrit-ui/app/scripts/gr-email-suggestions-provider/gr-email-suggestions-provider_test.html
+++ b/polygerrit-ui/app/scripts/gr-email-suggestions-provider/gr-email-suggestions-provider_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-email-suggestions-provider</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
@@ -68,7 +68,7 @@
     test('getSuggestions', done => {
       const getSuggestedAccountsStub =
           sandbox.stub(restAPI, 'getSuggestedAccounts')
-            .returns(Promise.resolve([account1, account2]));
+              .returns(Promise.resolve([account1, account2]));
 
       provider.getSuggestions('Some input').then(res => {
         assert.deepEqual(res, [account1, account2]);
diff --git a/polygerrit-ui/app/scripts/gr-group-suggestions-provider/gr-group-suggestions-provider_test.html b/polygerrit-ui/app/scripts/gr-group-suggestions-provider/gr-group-suggestions-provider_test.html
index b60aaa9..6908256 100644
--- a/polygerrit-ui/app/scripts/gr-group-suggestions-provider/gr-group-suggestions-provider_test.html
+++ b/polygerrit-ui/app/scripts/gr-group-suggestions-provider/gr-group-suggestions-provider_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-group-suggestions-provider</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider.js b/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider.js
index c83e5a2..6b97cf6 100644
--- a/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider.js
+++ b/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider.js
@@ -35,14 +35,15 @@
       switch (usersType) {
         case Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.REVIEWER:
           return new GrReviewerSuggestionsProvider(restApi, changeNumber,
-            input => restApi.getChangeSuggestedReviewers(changeNumber, input));
+              input =>
+                restApi.getChangeSuggestedReviewers(changeNumber, input));
         case Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.CC:
           return new GrReviewerSuggestionsProvider(restApi, changeNumber,
-            input => restApi.getChangeSuggestedCCs(changeNumber, input));
+              input => restApi.getChangeSuggestedCCs(changeNumber, input));
         case Gerrit.SUGGESTIONS_PROVIDERS_USERS_TYPES.ANY:
           return new GrReviewerSuggestionsProvider(restApi, changeNumber,
-            input => restApi.getSuggestedAccounts(
-                `cansee:${changeNumber} ${input}`));
+              input => restApi.getSuggestedAccounts(
+                  `cansee:${changeNumber} ${input}`));
         default:
           throw new Error(`Unknown users type: ${usersType}`);
       }
@@ -65,9 +66,9 @@
         this._loggedIn = loggedIn;
       });
       this._initPromise = Promise.all([getConfigPromise, getLoggedInPromise])
-        .then(() => {
-          this._initialized = true;
-        });
+          .then(() => {
+            this._initialized = true;
+          });
       return this._initPromise;
     }
 
diff --git a/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider_test.html b/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider_test.html
index ca3c277..6fcc4dc 100644
--- a/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider_test.html
+++ b/polygerrit-ui/app/scripts/gr-reviewer-suggestions-provider/gr-reviewer-suggestions-provider_test.html
@@ -18,7 +18,7 @@
 
 <meta name="viewport" content="width=device-width, minimum-scale=1.0, initial-scale=1.0, user-scalable=yes">
 <title>gr-reviewer-suggestions-provider</title>
-<script src="/test/common-test-setup.js"></script>
+
 <script src="/bower_components/webcomponentsjs/custom-elements-es5-adapter.js"></script>
 
 <script src="/bower_components/webcomponentsjs/webcomponents-lite.js"></script>
diff --git a/polygerrit-ui/app/styles/gr-change-metadata-shared-styles.html b/polygerrit-ui/app/styles/gr-change-metadata-shared-styles.html
index fef3872..84692ba 100644
--- a/polygerrit-ui/app/styles/gr-change-metadata-shared-styles.html
+++ b/polygerrit-ui/app/styles/gr-change-metadata-shared-styles.html
@@ -16,7 +16,9 @@
 -->
 <dom-module id="gr-change-metadata-shared-styles">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style>
       section {
         display: table-row;
diff --git a/polygerrit-ui/app/styles/gr-change-view-integration-shared-styles.html b/polygerrit-ui/app/styles/gr-change-view-integration-shared-styles.html
index 834f64a..5c5194c 100644
--- a/polygerrit-ui/app/styles/gr-change-view-integration-shared-styles.html
+++ b/polygerrit-ui/app/styles/gr-change-view-integration-shared-styles.html
@@ -25,7 +25,9 @@
 -->
 <dom-module id="gr-change-view-integration-shared-styles">
   <template>
-    <style include="shared-styles"></style>
+    <style include="shared-styles">
+      /* Workaround for empty style block - see https://github.com/Polymer/tools/issues/408 */
+    </style>
     <style>
       .header {
         color: var(--primary-text-color);
diff --git a/polygerrit-ui/app/styles/gr-form-styles.html b/polygerrit-ui/app/styles/gr-form-styles.html
index 3fe0a72..7c9ae0d 100644
--- a/polygerrit-ui/app/styles/gr-form-styles.html
+++ b/polygerrit-ui/app/styles/gr-form-styles.html
@@ -61,7 +61,6 @@
       }
       .gr-form-styles td,
       .gr-form-styles tfoot th {
-        height: 2em;
         padding: var(--spacing-s) 0;
         vertical-align: middle;
       }
@@ -84,8 +83,7 @@
       .gr-form-styles textarea {
         border: 1px solid var(--border-color);
         border-radius: var(--border-radius);
-        height: 2em;
-        padding: 0 var(--spacing-xs);
+        padding: var(--spacing-s);
       }
       .gr-form-styles td:last-child {
         width: 5em;
@@ -97,23 +95,16 @@
       .gr-form-styles iron-autogrow-textarea {
         border: none;
         height: auto;
-        min-height: 2em;
+        min-height: 4em;
         --iron-autogrow-textarea: {
           border: 1px solid var(--border-color);
           border-radius: var(--border-radius);
           box-sizing: border-box;
-          padding: var(--spacing-s) var(--spacing-xs) 0 var(--spacing-xs);
+          padding: var(--spacing-s);
         }
       }
       .gr-form-styles gr-autocomplete {
-        border: none;
-        --gr-autocomplete: {
-          border: 1px solid var(--border-color);
-          border-radius: var(--border-radius);
-          height: 2em;
-          padding: 0 var(--spacing-xs);
-          width: 14em;
-        }
+        width: 14em;
       }
       @media only screen and (max-width: 40em) {
         .gr-form-styles section {
diff --git a/polygerrit-ui/app/styles/shared-styles.html b/polygerrit-ui/app/styles/shared-styles.html
index 5314741..51b92e1 100644
--- a/polygerrit-ui/app/styles/shared-styles.html
+++ b/polygerrit-ui/app/styles/shared-styles.html
@@ -42,10 +42,11 @@
       input {
         background-color: inherit;
         border: 1px solid var(--border-color);
+        border-radius: var(--border-radius);
         box-sizing: border-box;
         color: var(--primary-text-color);
         margin: 0;
-        padding: 0;
+        padding: var(--spacing-s);
       }
       iron-autogrow-textarea {
         background-color: inherit;
diff --git a/polygerrit-ui/app/styles/themes/app-theme.html b/polygerrit-ui/app/styles/themes/app-theme.html
index 56add09..3a620d2 100644
--- a/polygerrit-ui/app/styles/themes/app-theme.html
+++ b/polygerrit-ui/app/styles/themes/app-theme.html
@@ -45,6 +45,7 @@
   --assignee-highlight-color: #fcfad6;
   --chip-background-color: #eee;
   --comment-background-color: #fcfad6;
+  --robot-comment-background-color: #e8f0fe;
   --default-button-background-color: white;
   --dialog-background-color: white;
   --dropdown-background-color: white;
@@ -74,7 +75,7 @@
 
   /* fonts */
   --font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji', 'Segoe UI Symbol';
-  --monospace-font-family: 'Roboto Mono', Menlo, 'Lucida Console', Monaco, monospace;
+  --monospace-font-family: 'Roboto Mono', 'SF Mono', 'Lucida Console', Monaco, monospace;
   --font-size-code: 12px;     /* 12px mono */
   --font-size-mono: .929rem;  /* 13px mono */
   --font-size-small: .857rem; /* 12px */
@@ -133,6 +134,8 @@
   --light-rebased-add-highlight-color: #eef;
   --light-remove-add-highlight-color: #fff8dc;
   --light-remove-highlight-color: #ffebee;
+  --coverage-covered: #e0f2f1;
+  --coverage-not-covered: #ffd1a4;
 
   /* syntax colors */
   --syntax-attr-color: #219;
@@ -164,6 +167,7 @@
   /* misc */
   --border-radius: 4px;
   --reply-overlay-z-index: 1000;
+  --iron-overlay-backdrop-opacity: 0.32;
   --iron-overlay-backdrop: {
     transition: none;
   };
diff --git a/polygerrit-ui/app/styles/themes/dark-theme.html b/polygerrit-ui/app/styles/themes/dark-theme.html
index 957cc25..4a91774 100644
--- a/polygerrit-ui/app/styles/themes/dark-theme.html
+++ b/polygerrit-ui/app/styles/themes/dark-theme.html
@@ -45,6 +45,7 @@
       --assignee-highlight-color: #3a361c;
       --chip-background-color: #131416;
       --comment-background-color: #0b162b;
+      --robot-comment-background-color: #e8f0fe;
       --default-button-background-color: #3c4043;
       --dialog-background-color: #131416;
       --dropdown-background-color: #131416;
@@ -103,6 +104,8 @@
       --light-rebased-add-highlight-color: #487165;
       --light-remove-add-highlight-color: #2f3f2f;
       --light-remove-highlight-color: #320404;
+      --coverage-covered: #e0f2f1;
+      --coverage-not-covered: #ffd1a4;
 
       /* syntax colors */
       --syntax-attr-color: #80cbbf;
diff --git a/polygerrit-ui/app/template_test.sh b/polygerrit-ui/app/template_test.sh
index b1a2380..ccefd83 100755
--- a/polygerrit-ui/app/template_test.sh
+++ b/polygerrit-ui/app/template_test.sh
@@ -1,5 +1,11 @@
 #!/bin/bash
 
+# TODO(dmfilippov): Update template_test to support Polymer 2/Polymer 3 or delete it completely
+# The following line temporary disable template tests. Existing implementation doesn't compatible
+# with Polymer 2 & 3 class-based components. Polymer linter makes some checks regarding
+# templates and binding, but not all.
+exit 0
+
 set -ex
 
 node_bin=$(which node)
diff --git a/polygerrit-ui/app/test/common-test-setup.js b/polygerrit-ui/app/test/common-test-setup.js
deleted file mode 100644
index 7ceff7e..0000000
--- a/polygerrit-ui/app/test/common-test-setup.js
+++ /dev/null
@@ -1,26 +0,0 @@
-/**
- * @license
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-/**
- * Helps looking up the proper iron-input element during the Polymer 2
- * transition. Polymer 2 uses the <iron-input> element, while Polymer 1 uses
- * the nested <input is="iron-input"> element.
- */
-window.ironInput = function(element) {
-  return Polymer.dom(element).querySelector(
-      Polymer.Element ? 'iron-input' : 'input[is=iron-input]');
-};
diff --git a/polygerrit-ui/app/types/polymer-behaviors.js b/polygerrit-ui/app/types/polymer-behaviors.js
new file mode 100644
index 0000000..18e7ad9
--- /dev/null
+++ b/polygerrit-ui/app/types/polymer-behaviors.js
@@ -0,0 +1,52 @@
+/**
+ * @license
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * For the purposes of template type checking, externs should be added for
+ * anything set on the window object. Note that sub-properties of these
+ * declared properties are considered something separate.
+ *
+ * This file is only for template type checking, not used in Gerrit code.
+ */
+
+/* eslint-disable no-var */
+/* eslint-disable no-unused-vars */
+
+function PolymerMixins() {
+  // This function must not be called.
+  // Due to an issue in polymer linter the linter can't
+  // process correctly some behaviors from Polymer library.
+  // To workaround this issue, here we define a minimal mixin to allow
+  // linter process our code correctly. You can add more properties to mixins
+  // if needed.
+
+  // Important! Use mixins from these file only inside JSDoc comments.
+  // Do not use it in the real code
+
+  /**
+   * @polymer
+   * @mixinFunction
+   * */
+  Polymer.IronFitMixin = base =>
+    class extends base {
+      static get properties() {
+        return {
+          positionTarget: Object,
+        };
+      }
+    };
+}
diff --git a/polygerrit-ui/server.go b/polygerrit-ui/server.go
index 1a2d299..3b699c2 100644
--- a/polygerrit-ui/server.go
+++ b/polygerrit-ui/server.go
@@ -43,6 +43,8 @@
 	host                  = flag.String("host", "gerrit-review.googlesource.com", "Host to proxy requests to")
 	scheme                = flag.String("scheme", "https", "URL scheme")
 	cdnPattern            = regexp.MustCompile("https://cdn.googlesource.com/polygerrit_ui/[0-9.]*")
+	webComponentPattern   = regexp.MustCompile("webcomponentsjs-p2")
+	grAppPattern = regexp.MustCompile("gr-app-p2")
 	bundledPluginsPattern = regexp.MustCompile("https://cdn.googlesource.com/polygerrit_assets/[0-9.]*")
 )
 
@@ -84,6 +86,9 @@
 		log.Println("Local plugins from", "../plugins")
 	} else {
 		http.HandleFunc("/plugins/", handleProxy)
+		// Serve local plugins from `plugins_`
+		http.Handle("/plugins_/", http.StripPrefix("/plugins_/",
+			http.FileServer(http.Dir("../plugins"))))
 	}
 	log.Println("Serving on port", *port)
 	log.Fatal(http.ListenAndServe(*port, &server{}))
@@ -184,9 +189,13 @@
 	buf.ReadFrom(reader)
 	original := buf.String()
 
+	// Replace the webcomponentsjs-p2 with webcomponentsjs
+	replaced := webComponentPattern.ReplaceAllString(original, "webcomponentsjs")
+	replaced = grAppPattern.ReplaceAllString(replaced, "gr-app")
+
 	// Simply remove all CDN references, so files are loaded from the local file system  or the proxy
 	// server instead.
-	replaced := cdnPattern.ReplaceAllString(original, "")
+	replaced = cdnPattern.ReplaceAllString(replaced, "")
 
 	// Modify window.INITIAL_DATA so that it has the same effect as injectLocalPlugins. To achieve
 	// this let's add JavaScript lines at the end of the <script>...</script> snippet that also
diff --git a/prologtests/examples/BUILD b/prologtests/examples/BUILD
index f4ebe90..ebf2c68 100644
--- a/prologtests/examples/BUILD
+++ b/prologtests/examples/BUILD
@@ -1,15 +1,12 @@
 package(default_visibility = ["//visibility:public"])
 
-DUMMY = ["dummy.sh"]
-
-# Enable prologtests on newer Java versions again, when this Bazel bug is fixed:
-# https://github.com/bazelbuild/bazel/issues/9391
 sh_test(
     name = "test_examples",
-    srcs = select({
-        "//:java11": DUMMY,
-        "//:java_next": DUMMY,
-        "//conditions:default": ["run.sh"],
-    }),
-    data = glob(["*.pl"]) + ["//:gerrit.war"],
+    srcs = ["run.sh"],
+    args = ["$(JAVA)"],
+    data = glob(["*.pl"]) + [
+        "//:gerrit.war",
+        "@bazel_tools//tools/jdk:current_host_java_runtime",
+    ],
+    toolchains = ["@bazel_tools//tools/jdk:current_host_java_runtime"],
 )
diff --git a/prologtests/examples/run.sh b/prologtests/examples/run.sh
index 947c153..b2883ebe 100755
--- a/prologtests/examples/run.sh
+++ b/prologtests/examples/run.sh
@@ -1,5 +1,14 @@
 #!/bin/bash
 
+# TODO(davido): Figure out what to do if running alone and not invoked from bazel
+# $1 is equal to the $(JAVABASE)/bin/java make variable
+JAVA=$1
+
+# Checks whether or not the $1 is starting with a slash: '/' and thus considered to be
+# an absolute path. If it is, then it is left as is, if it isn't then "$PWD/ is prepended
+# (in sh_test case it is relative and thus the runfiles directory is prepended).
+[[ "$JAVA" =~ ^(/|[^/]+$) ]] || JAVA="$PWD/$JAVA"
+
 TESTS="t1 t2 t3"
 
 # Note that both t1.pl and t2.pl test code in rules.pl.
@@ -36,7 +45,7 @@
   # Unit tests do not need to define clauses in packages.
   # Use one prolog-shell per unit test, to avoid name collision.
   echo "### Running test ${T}.pl"
-  echo "[$T]." | java -jar ${GERRIT_WAR} prolog-shell -q -s load.pl
+  echo "[$T]." | "${JAVA}" -jar ${GERRIT_WAR} prolog-shell -q -s load.pl
 
   if [ "x$?" != "x0" ]; then
     echo "### Test ${T}.pl failed."
diff --git a/tools/BUILD b/tools/BUILD
index 5531c3e..f0a4ffa 100644
--- a/tools/BUILD
+++ b/tools/BUILD
@@ -53,6 +53,7 @@
         "-Xep:ExpectedExceptionChecker:ERROR",
         "-Xep:Finally:ERROR",
         "-Xep:FloatingPointLiteralPrecision:ERROR",
+        "-Xep:FormatStringAnnotation:ERROR",
         "-Xep:FragmentInjection:ERROR",
         "-Xep:FragmentNotInstantiable:ERROR",
         "-Xep:FunctionalInterfaceClash:ERROR",
diff --git a/tools/bzl/maven_jar.bzl b/tools/bzl/maven_jar.bzl
index fa5cbd1..0b4a52a 100644
--- a/tools/bzl/maven_jar.bzl
+++ b/tools/bzl/maven_jar.bzl
@@ -146,7 +146,6 @@
 
     parts = ctx.attr.artifact.split(":")
 
-    # TODO(davido): Only releases for now, implement handling snapshots
     jar, url = _maven_release(ctx, parts)
 
     binjar = jar + ".jar"
diff --git a/tools/maven/gerrit-acceptance-framework_pom.xml b/tools/maven/gerrit-acceptance-framework_pom.xml
index 1b0f3f2..4240a9b 100644
--- a/tools/maven/gerrit-acceptance-framework_pom.xml
+++ b/tools/maven/gerrit-acceptance-framework_pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.gerrit</groupId>
   <artifactId>gerrit-acceptance-framework</artifactId>
-  <version>3.1.1-SNAPSHOT</version>
+  <version>3.2.0-SNAPSHOT</version>
   <packaging>jar</packaging>
   <name>Gerrit Code Review - Acceptance Test Framework</name>
   <description>Framework for Gerrit's acceptance tests</description>
diff --git a/tools/maven/gerrit-extension-api_pom.xml b/tools/maven/gerrit-extension-api_pom.xml
index a6efa4c..cf2b080 100644
--- a/tools/maven/gerrit-extension-api_pom.xml
+++ b/tools/maven/gerrit-extension-api_pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.gerrit</groupId>
   <artifactId>gerrit-extension-api</artifactId>
-  <version>3.1.1-SNAPSHOT</version>
+  <version>3.2.0-SNAPSHOT</version>
   <packaging>jar</packaging>
   <name>Gerrit Code Review - Extension API</name>
   <description>API for Gerrit Extensions</description>
diff --git a/tools/maven/gerrit-plugin-api_pom.xml b/tools/maven/gerrit-plugin-api_pom.xml
index 2d0f19c..7d3c4f0 100644
--- a/tools/maven/gerrit-plugin-api_pom.xml
+++ b/tools/maven/gerrit-plugin-api_pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.gerrit</groupId>
   <artifactId>gerrit-plugin-api</artifactId>
-  <version>3.1.1-SNAPSHOT</version>
+  <version>3.2.0-SNAPSHOT</version>
   <packaging>jar</packaging>
   <name>Gerrit Code Review - Plugin API</name>
   <description>API for Gerrit Plugins</description>
diff --git a/tools/maven/gerrit-war_pom.xml b/tools/maven/gerrit-war_pom.xml
index a1c228b..9478283 100644
--- a/tools/maven/gerrit-war_pom.xml
+++ b/tools/maven/gerrit-war_pom.xml
@@ -2,7 +2,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.google.gerrit</groupId>
   <artifactId>gerrit-war</artifactId>
-  <version>3.1.1-SNAPSHOT</version>
+  <version>3.2.0-SNAPSHOT</version>
   <packaging>war</packaging>
   <name>Gerrit Code Review - WAR</name>
   <description>Gerrit WAR</description>
diff --git a/tools/nongoogle.bzl b/tools/nongoogle.bzl
index eb1372a..1dfc2f4 100644
--- a/tools/nongoogle.bzl
+++ b/tools/nongoogle.bzl
@@ -23,8 +23,8 @@
 
     maven_jar(
         name = "dropwizard-core",
-        artifact = "io.dropwizard.metrics:metrics-core:4.0.7",
-        sha1 = "673899f605f52ca35836673ccfee97154a496a61",
+        artifact = "io.dropwizard.metrics:metrics-core:4.1.1",
+        sha1 = "ebfafc716d9c3b6151dc7c2c09ce925a163a4f21",
     )
 
     SSHD_VERS = "2.3.0"
diff --git a/tools/polygerrit-updater/.gitignore b/tools/polygerrit-updater/.gitignore
new file mode 100644
index 0000000..8619a37
--- /dev/null
+++ b/tools/polygerrit-updater/.gitignore
@@ -0,0 +1,3 @@
+/.idea/
+/node_modules/
+/js/
\ No newline at end of file
diff --git a/tools/polygerrit-updater/package-lock.json b/tools/polygerrit-updater/package-lock.json
new file mode 100644
index 0000000..9256997
--- /dev/null
+++ b/tools/polygerrit-updater/package-lock.json
@@ -0,0 +1,18 @@
+{
+  "name": "polygerrit-updater",
+  "version": "1.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
+    "@types/node": {
+      "version": "12.7.12",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-12.7.12.tgz",
+      "integrity": "sha512-KPYGmfD0/b1eXurQ59fXD1GBzhSQfz6/lKBxkaHX9dKTzjXbK68Zt7yGUxUsCS1jeTy/8aL+d9JEr+S54mpkWQ=="
+    },
+    "typescript": {
+      "version": "3.6.4",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.6.4.tgz",
+      "integrity": "sha512-unoCll1+l+YK4i4F8f22TaNVPRHcD9PA3yCuZ8g5e0qGqlVlJ/8FSateOLLSagn+Yg5+ZwuPkL8LFUc0Jcvksg=="
+    }
+  }
+}
diff --git a/tools/polygerrit-updater/package.json b/tools/polygerrit-updater/package.json
new file mode 100644
index 0000000..3609dad
--- /dev/null
+++ b/tools/polygerrit-updater/package.json
@@ -0,0 +1,15 @@
+{
+  "name": "polygerrit-updater",
+  "version": "1.0.0",
+  "description": "Polygerrit source code updater",
+  "scripts": {
+    "compile": "tsc",
+    "convert": "npm run compile && node js/src/index.js"
+  },
+  "author": "",
+  "license": "Apache-2.0",
+  "dependencies": {
+    "@types/node": "^12.7.12",
+    "typescript": "^3.6.4"
+  }
+}
diff --git a/tools/polygerrit-updater/readme.txt b/tools/polygerrit-updater/readme.txt
new file mode 100644
index 0000000..2b2cea8
--- /dev/null
+++ b/tools/polygerrit-updater/readme.txt
@@ -0,0 +1,56 @@
+This folder contains tool to update Polymer components to class based components.
+This is a temporary tools, it will be removed in a few weeks.
+
+How to use this tool: initial steps
+1) Important - Commit and push all your changes. Otherwise, you can loose you work.
+
+2) Ensure, that tools/polygerrit-updater is your current directory
+
+3) Run
+npm install
+
+4) If you want to convert the whole project, run
+npm run convert -- --i \
+  --root ../../polygerrit-ui --src app/elements --r \
+  --exclude app/elements/core/gr-reporting/gr-reporting.js \
+     app/elements/diff/gr-comment-api/gr-comment-api-mock.js \
+     app/elements/plugins/gr-dom-hooks/gr-dom-hooks.js
+
+You can convert only specific files (can be useful if you want to convert some files in your change)
+npm run convert -- --i \
+  --root ../../polygerrit-ui
+  --src app/elements/file1.js \
+      app/elements/folder/file2.js
+
+4) Search for the following string in all .js files:
+//This file has the following problems with comments:
+
+If you find such string in a .js file - you must manually fix comments in this file.
+(It is expected that you shouldn't have such problems)
+
+5) Go to the gerrit root folder and run
+npm run eslintfix
+
+(If you are doing it for the first time, run the following command before in gerrit root folder:
+npm run install)
+
+Fix error after eslintfix (if exists)
+
+6) If you are doing conversion for the whole project, make the followin changes:
+
+a) Add
+<link rel="import" href="../../../types/polymer-behaviors.js">
+to
+polygerrit-ui/app/elements/shared/gr-autocomplete-dropdown/gr-autocomplete-dropdown.html
+
+b) Update polymer.json with the following rules:
+  "lint": {
+    "rules": ["polymer-2"],
+    "ignoreWarnings": ["deprecated-dom-call"]
+  }
+
+
+
+5) Commit changed files.
+
+6) You can update excluded files later.
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/funcToClassBasedElementConverter.ts b/tools/polygerrit-updater/src/funcToClassConversion/funcToClassBasedElementConverter.ts
new file mode 100644
index 0000000..b92a6e9
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/funcToClassBasedElementConverter.ts
@@ -0,0 +1,131 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import {LegacyLifecycleMethodsArray, LegacyPolymerComponent} from './polymerComponentParser';
+import {LifecycleMethodsBuilder} from './lifecycleMethodsBuilder';
+import {ClassBasedPolymerElement, PolymerElementBuilder} from './polymerElementBuilder';
+import * as codeUtils from '../utils/codeUtils';
+import * as ts from 'typescript';
+
+export class PolymerFuncToClassBasedConverter {
+  public static convert(component: LegacyPolymerComponent): ClassBasedPolymerElement {
+    const legacySettings = component.componentSettings;
+    const reservedDeclarations = legacySettings.reservedDeclarations;
+
+    if(!reservedDeclarations.is) {
+      throw new Error("Legacy component doesn't have 'is' property");
+    }
+    const className = this.generateClassNameFromTagName(reservedDeclarations.is.data);
+    const updater = new PolymerElementBuilder(component, className);
+    updater.addIsAccessor(reservedDeclarations.is.data);
+
+    if(reservedDeclarations.properties) {
+      updater.addPolymerPropertiesAccessor(reservedDeclarations.properties);
+    }
+
+    updater.addMixin("Polymer.Element");
+    updater.addMixin("Polymer.LegacyElementMixin");
+    updater.addMixin("Polymer.GestureEventListeners");
+
+    if(reservedDeclarations._legacyUndefinedCheck) {
+      updater.addMixin("Polymer.LegacyDataMixin");
+    }
+
+    if(reservedDeclarations.behaviors) {
+      updater.addMixin("Polymer.mixinBehaviors", [reservedDeclarations.behaviors.data]);
+      const mixinNames = this.getMixinNamesFromBehaviors(reservedDeclarations.behaviors.data);
+      const jsDocLines = mixinNames.map(mixinName => {
+        return `@appliesMixin ${mixinName}`;
+      });
+      updater.addClassJSDocComments(jsDocLines);
+    }
+
+    if(reservedDeclarations.observers) {
+      updater.addPolymerPropertiesObservers(reservedDeclarations.observers.data);
+    }
+
+    if(reservedDeclarations.keyBindings) {
+      updater.addKeyBindings(reservedDeclarations.keyBindings.data);
+    }
+
+
+    const lifecycleBuilder = new LifecycleMethodsBuilder();
+    if (reservedDeclarations.listeners) {
+      lifecycleBuilder.addListeners(reservedDeclarations.listeners.data, legacySettings.ordinaryMethods);
+    }
+
+    if (reservedDeclarations.hostAttributes) {
+      lifecycleBuilder.addHostAttributes(reservedDeclarations.hostAttributes.data);
+    }
+
+    for(const name of LegacyLifecycleMethodsArray) {
+      const existingMethod = legacySettings.lifecycleMethods.get(name);
+      if(existingMethod) {
+        lifecycleBuilder.addLegacyLifecycleMethod(name, existingMethod)
+      }
+    }
+
+    const newLifecycleMethods = lifecycleBuilder.buildNewMethods();
+    updater.addLifecycleMethods(newLifecycleMethods);
+
+
+    updater.addOrdinaryMethods(legacySettings.ordinaryMethods);
+    updater.addOrdinaryGetAccessors(legacySettings.ordinaryGetAccessors);
+    updater.addOrdinaryShorthandProperties(legacySettings.ordinaryShorthandProperties);
+    updater.addOrdinaryPropertyAssignments(legacySettings.ordinaryPropertyAssignments);
+
+    return updater.build();
+  }
+
+  private static generateClassNameFromTagName(tagName: string) {
+    let result = "";
+    let nextUppercase = true;
+    for(const ch of tagName) {
+      if (ch === '-') {
+        nextUppercase = true;
+        continue;
+      }
+      result += nextUppercase ? ch.toUpperCase() : ch;
+      nextUppercase = false;
+    }
+    return result;
+  }
+
+  private static getMixinNamesFromBehaviors(behaviors: ts.ArrayLiteralExpression): string[] {
+    return behaviors.elements.map((expression) => {
+      const propertyAccessExpression = codeUtils.assertNodeKind(expression, ts.SyntaxKind.PropertyAccessExpression) as ts.PropertyAccessExpression;
+      const namespaceName = codeUtils.assertNodeKind(propertyAccessExpression.expression, ts.SyntaxKind.Identifier) as ts.Identifier;
+      const behaviorName = propertyAccessExpression.name;
+      if(namespaceName.text === 'Gerrit') {
+        let behaviorNameText = behaviorName.text;
+        const suffix = 'Behavior';
+        if(behaviorNameText.endsWith(suffix)) {
+          behaviorNameText =
+              behaviorNameText.substr(0, behaviorNameText.length - suffix.length);
+        }
+        const mixinName = behaviorNameText + 'Mixin';
+        return `${namespaceName.text}.${mixinName}`
+      } else if(namespaceName.text === 'Polymer') {
+        let behaviorNameText = behaviorName.text;
+        if(behaviorNameText === "IronFitBehavior") {
+          return "Polymer.IronFitMixin";
+        } else if(behaviorNameText === "IronOverlayBehavior") {
+          return "";
+        }
+        throw new Error(`Unsupported behavior: ${propertyAccessExpression.getText()}`);
+      }
+      throw new Error(`Unsupported behavior name ${expression.getFullText()}`)
+    }).filter(name => name.length > 0);
+  }
+}
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/legacyPolymerFuncReplacer.ts b/tools/polygerrit-updater/src/funcToClassConversion/legacyPolymerFuncReplacer.ts
new file mode 100644
index 0000000..57b7b8d
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/legacyPolymerFuncReplacer.ts
@@ -0,0 +1,74 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as ts from 'typescript';
+import * as codeUtils from '../utils/codeUtils'
+import {LegacyPolymerComponent} from './polymerComponentParser';
+import {ClassBasedPolymerElement} from './polymerElementBuilder';
+
+export class LegacyPolymerFuncReplaceResult {
+  public constructor(
+      private readonly transformationResult: ts.TransformationResult<ts.SourceFile>,
+      public readonly leadingComments: string[]) {
+  }
+  public get file(): ts.SourceFile {
+    return this.transformationResult.transformed[0];
+  }
+  public dispose() {
+    this.transformationResult.dispose();
+  }
+
+}
+
+export class LegacyPolymerFuncReplacer {
+  private readonly callStatement: ts.ExpressionStatement;
+  private readonly parentBlock: ts.Block;
+  private readonly callStatementIndexInBlock: number;
+  public constructor(private readonly legacyComponent: LegacyPolymerComponent) {
+    this.callStatement = codeUtils.assertNodeKind(legacyComponent.polymerFuncCallExpr.parent, ts.SyntaxKind.ExpressionStatement);
+    this.parentBlock = codeUtils.assertNodeKind(this.callStatement.parent, ts.SyntaxKind.Block);
+    this.callStatementIndexInBlock = this.parentBlock.statements.indexOf(this.callStatement);
+    if(this.callStatementIndexInBlock < 0) {
+      throw new Error("Internal error! Couldn't find statement in its own parent");
+    }
+  }
+  public replace(classBasedElement: ClassBasedPolymerElement): LegacyPolymerFuncReplaceResult {
+    const classDeclarationWithComments = this.appendLeadingCommentToClassDeclaration(classBasedElement.classDeclaration);
+    return new LegacyPolymerFuncReplaceResult(
+        this.replaceLegacyPolymerFunction(classDeclarationWithComments.classDeclarationWithCommentsPlaceholder, classBasedElement.componentRegistration),
+        classDeclarationWithComments.leadingComments);
+  }
+  private appendLeadingCommentToClassDeclaration(classDeclaration: ts.ClassDeclaration): {classDeclarationWithCommentsPlaceholder: ts.ClassDeclaration, leadingComments: string[]} {
+    const text = this.callStatement.getFullText();
+    let classDeclarationWithCommentsPlaceholder = classDeclaration;
+    const leadingComments: string[] = [];
+    ts.forEachLeadingCommentRange(text, 0, (pos, end, kind, hasTrailingNewLine) => {
+      classDeclarationWithCommentsPlaceholder = codeUtils.addReplacableCommentBeforeNode(classDeclarationWithCommentsPlaceholder, String(leadingComments.length));
+      leadingComments.push(text.substring(pos, end));
+    });
+    return {
+      classDeclarationWithCommentsPlaceholder: classDeclarationWithCommentsPlaceholder,
+      leadingComments: leadingComments
+    }
+  }
+  private replaceLegacyPolymerFunction(classDeclaration: ts.ClassDeclaration, componentRegistration: ts.ExpressionStatement): ts.TransformationResult<ts.SourceFile> {
+    const newStatements = Array.from(this.parentBlock.statements);
+    newStatements.splice(this.callStatementIndexInBlock, 1, classDeclaration, componentRegistration);
+
+    const updatedBlock = ts.getMutableClone(this.parentBlock);
+    updatedBlock.statements = ts.createNodeArray(newStatements);
+    return codeUtils.replaceNode(this.legacyComponent.parsedFile, this.parentBlock, updatedBlock);
+
+  }
+}
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/lifecycleMethodsBuilder.ts b/tools/polygerrit-updater/src/funcToClassConversion/lifecycleMethodsBuilder.ts
new file mode 100644
index 0000000..e9e13f5
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/lifecycleMethodsBuilder.ts
@@ -0,0 +1,140 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as ts from 'typescript';
+import * as codeUtils from '../utils/codeUtils';
+import {LegacyLifecycleMethodName, OrdinaryMethods} from './polymerComponentParser';
+
+interface LegacyLifecycleMethodContent {
+  codeAtMethodStart: ts.Statement[];
+  existingMethod?: ts.MethodDeclaration;
+  codeAtMethodEnd: ts.Statement[];
+}
+
+export interface LifecycleMethod {
+  originalPos: number;//-1 - no original method exists
+  method: ts.MethodDeclaration;
+  name: LegacyLifecycleMethodName;
+}
+
+export class LifecycleMethodsBuilder {
+  private readonly methods: Map<LegacyLifecycleMethodName, LegacyLifecycleMethodContent> = new Map();
+
+  private getMethodContent(name: LegacyLifecycleMethodName): LegacyLifecycleMethodContent {
+    if(!this.methods.has(name)) {
+      this.methods.set(name, {
+        codeAtMethodStart: [],
+        codeAtMethodEnd: []
+      });
+    }
+    return this.methods.get(name)!;
+  }
+
+  public addListeners(legacyListeners: ts.ObjectLiteralExpression, legacyOrdinaryMethods: OrdinaryMethods) {
+    for(const listener of legacyListeners.properties) {
+      const propertyAssignment = codeUtils.assertNodeKind(listener, ts.SyntaxKind.PropertyAssignment) as ts.PropertyAssignment;
+      if(!propertyAssignment.name) {
+        throw new Error("Listener must have event name");
+      }
+      let eventNameLiteral: ts.StringLiteral;
+      let commentsToRestore: string[] = [];
+      if(propertyAssignment.name.kind === ts.SyntaxKind.StringLiteral) {
+        //We don't loose comment in this case, because we keep literal as is
+        eventNameLiteral = propertyAssignment.name;
+      } else if(propertyAssignment.name.kind === ts.SyntaxKind.Identifier) {
+        eventNameLiteral = ts.createStringLiteral(propertyAssignment.name.text);
+        commentsToRestore = codeUtils.getLeadingComments(propertyAssignment);
+      } else {
+        throw new Error(`Unsupported type ${ts.SyntaxKind[propertyAssignment.name.kind]}`);
+      }
+
+      const handlerLiteral = codeUtils.assertNodeKind(propertyAssignment.initializer, ts.SyntaxKind.StringLiteral) as ts.StringLiteral;
+      const handlerImpl = legacyOrdinaryMethods.get(handlerLiteral.text);
+      if(!handlerImpl) {
+        throw new Error(`Can't find event handler '${handlerLiteral.text}'`);
+      }
+      const eventHandlerAccess = ts.createPropertyAccess(ts.createThis(), handlerLiteral.text);
+      //ts.forEachChild(handler)
+      const args: ts.Identifier[] = handlerImpl.parameters.map((arg) => codeUtils.assertNodeKind(arg.name, ts.SyntaxKind.Identifier));
+      const eventHandlerCall = ts.createCall(eventHandlerAccess, [], args);
+      let arrowFunc = ts.createArrowFunction([], [], handlerImpl.parameters, undefined, undefined, eventHandlerCall);
+      arrowFunc = codeUtils.addNewLineBeforeNode(arrowFunc);
+
+      const methodContent = this.getMethodContent("created");
+      //See https://polymer-library.polymer-project.org/3.0/docs/devguide/gesture-events for a list of events
+      if(["down", "up", "tap", "track"].indexOf(eventNameLiteral.text) >= 0) {
+        const methodCall = ts.createCall(codeUtils.createNameExpression("Polymer.Gestures.addListener"), [], [ts.createThis(), eventNameLiteral, arrowFunc]);
+        methodContent.codeAtMethodEnd.push(ts.createExpressionStatement(methodCall));
+      }
+      else {
+        let methodCall = ts.createCall(ts.createPropertyAccess(ts.createThis(), "addEventListener"), [], [eventNameLiteral, arrowFunc]);
+        methodCall = codeUtils.restoreLeadingComments(methodCall, commentsToRestore);
+        methodContent.codeAtMethodEnd.push(ts.createExpressionStatement(methodCall));
+      }
+    }
+  }
+
+  public addHostAttributes(legacyHostAttributes: ts.ObjectLiteralExpression) {
+    for(const listener of legacyHostAttributes.properties) {
+      const propertyAssignment = codeUtils.assertNodeKind(listener, ts.SyntaxKind.PropertyAssignment) as ts.PropertyAssignment;
+      if(!propertyAssignment.name) {
+        throw new Error("Listener must have event name");
+      }
+      let attributeNameLiteral: ts.StringLiteral;
+      if(propertyAssignment.name.kind === ts.SyntaxKind.StringLiteral) {
+        attributeNameLiteral = propertyAssignment.name;
+      } else if(propertyAssignment.name.kind === ts.SyntaxKind.Identifier) {
+        attributeNameLiteral = ts.createStringLiteral(propertyAssignment.name.text);
+      } else {
+        throw new Error(`Unsupported type ${ts.SyntaxKind[propertyAssignment.name.kind]}`);
+      }
+      let attributeValueLiteral: ts.StringLiteral | ts.NumericLiteral;
+      if(propertyAssignment.initializer.kind === ts.SyntaxKind.StringLiteral) {
+        attributeValueLiteral = propertyAssignment.initializer as ts.StringLiteral;
+      } else if(propertyAssignment.initializer.kind === ts.SyntaxKind.NumericLiteral) {
+        attributeValueLiteral = propertyAssignment.initializer as ts.NumericLiteral;
+      } else {
+        throw new Error(`Unsupported type ${ts.SyntaxKind[propertyAssignment.initializer.kind]}`);
+      }
+      const methodCall = ts.createCall(ts.createPropertyAccess(ts.createThis(), "_ensureAttribute"), [], [attributeNameLiteral, attributeValueLiteral]);
+      this.getMethodContent("ready").codeAtMethodEnd.push(ts.createExpressionStatement(methodCall));
+    }
+  }
+
+  public addLegacyLifecycleMethod(name: LegacyLifecycleMethodName, method: ts.MethodDeclaration) {
+    const content = this.getMethodContent(name);
+    if(content.existingMethod) {
+      throw new Error(`Legacy lifecycle method ${name} already added`);
+    }
+    content.existingMethod = method;
+  }
+
+  public buildNewMethods(): LifecycleMethod[] {
+    const result = [];
+    for(const [name, content] of this.methods) {
+      const newMethod = this.createLifecycleMethod(name, content.existingMethod, content.codeAtMethodStart, content.codeAtMethodEnd);
+      if(!newMethod) continue;
+      result.push({
+        name,
+        originalPos: content.existingMethod ? content.existingMethod.pos : -1,
+        method: newMethod
+      })
+    }
+    return result;
+  }
+
+  private createLifecycleMethod(name: string, methodDecl: ts.MethodDeclaration | undefined, codeAtStart: ts.Statement[], codeAtEnd: ts.Statement[]): ts.MethodDeclaration | undefined {
+    return codeUtils.createMethod(name, methodDecl, codeAtStart, codeAtEnd, true);
+  }
+}
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/polymerComponentParser.ts b/tools/polygerrit-updater/src/funcToClassConversion/polymerComponentParser.ts
new file mode 100644
index 0000000..6006608
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/polymerComponentParser.ts
@@ -0,0 +1,301 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as ts from "typescript";
+import * as fs from "fs";
+import * as path from "path";
+import { unexpectedValue } from "../utils/unexpectedValue";
+import * as codeUtils from "../utils/codeUtils";
+import {CommentsParser} from '../utils/commentsParser';
+
+export class LegacyPolymerComponentParser {
+  public constructor(private readonly rootDir: string, private readonly htmlFiles: Set<string>) {
+  }
+  public async parse(jsFile: string): Promise<ParsedPolymerComponent | null> {
+    const sourceFile: ts.SourceFile  = this.parseJsFile(jsFile);
+    const legacyComponent = this.tryParseLegacyComponent(sourceFile);
+    if (legacyComponent) {
+      return legacyComponent;
+    }
+    return null;
+  }
+  private parseJsFile(jsFile: string): ts.SourceFile {
+    return ts.createSourceFile(jsFile, fs.readFileSync(path.resolve(this.rootDir, jsFile)).toString(), ts.ScriptTarget.ES2015, true);
+  }
+
+  private tryParseLegacyComponent(sourceFile: ts.SourceFile): ParsedPolymerComponent | null {
+    const polymerFuncCalls: ts.CallExpression[] = [];
+
+    function addPolymerFuncCall(node: ts.Node) {
+      if(node.kind === ts.SyntaxKind.CallExpression) {
+        const callExpression: ts.CallExpression = node as ts.CallExpression;
+        if(callExpression.expression.kind === ts.SyntaxKind.Identifier) {
+          const identifier = callExpression.expression as ts.Identifier;
+          if(identifier.text === "Polymer") {
+            polymerFuncCalls.push(callExpression);
+          }
+        }
+      }
+      ts.forEachChild(node, addPolymerFuncCall);
+    }
+
+    addPolymerFuncCall(sourceFile);
+
+
+    if (polymerFuncCalls.length === 0) {
+      return null;
+    }
+    if (polymerFuncCalls.length > 1) {
+      throw new Error("Each .js file must contain only one Polymer component");
+    }
+    const parsedPath = path.parse(sourceFile.fileName);
+    const htmlFullPath = path.format({
+      dir: parsedPath.dir,
+      name: parsedPath.name,
+      ext: ".html"
+    });
+    if (!this.htmlFiles.has(htmlFullPath)) {
+      throw new Error("Legacy .js component dosn't have associated .html file");
+    }
+
+    const polymerFuncCall = polymerFuncCalls[0];
+    if(polymerFuncCall.arguments.length !== 1) {
+      throw new Error("The Polymer function must be called with exactly one parameter");
+    }
+    const argument = polymerFuncCall.arguments[0];
+    if(argument.kind !== ts.SyntaxKind.ObjectLiteralExpression) {
+      throw new Error("The parameter for Polymer function must be ObjectLiteralExpression (i.e. '{...}')");
+    }
+    const infoArg = argument as ts.ObjectLiteralExpression;
+
+    return {
+      jsFile: sourceFile.fileName,
+      htmlFile: htmlFullPath,
+      parsedFile: sourceFile,
+      polymerFuncCallExpr: polymerFuncCalls[0],
+      componentSettings: this.parseLegacyComponentSettings(infoArg),
+    };
+  }
+
+  private parseLegacyComponentSettings(info: ts.ObjectLiteralExpression): LegacyPolymerComponentSettings {
+    const props: Map<string, ts.ObjectLiteralElementLike> = new Map();
+    for(const property of info.properties) {
+      const name = property.name;
+      if (name === undefined) {
+        throw new Error("Property name is not defined");
+      }
+      switch(name.kind) {
+        case ts.SyntaxKind.Identifier:
+        case ts.SyntaxKind.StringLiteral:
+          if (props.has(name.text)) {
+            throw new Error(`Property ${name.text} appears more than once`);
+          }
+          props.set(name.text, property);
+          break;
+        case ts.SyntaxKind.ComputedPropertyName:
+          continue;
+        default:
+          unexpectedValue(ts.SyntaxKind[name.kind]);
+      }
+    }
+
+    if(props.has("_noAccessors")) {
+      throw new Error("_noAccessors is not supported");
+    }
+
+    const legacyLifecycleMethods: LegacyLifecycleMethods = new Map();
+    for(const name of LegacyLifecycleMethodsArray) {
+      const methodDecl = this.getLegacyMethodDeclaration(props, name);
+      if(methodDecl) {
+        legacyLifecycleMethods.set(name, methodDecl);
+      }
+    }
+
+    const ordinaryMethods: OrdinaryMethods = new Map();
+    const ordinaryShorthandProperties: OrdinaryShorthandProperties = new Map();
+    const ordinaryGetAccessors: OrdinaryGetAccessors = new Map();
+    const ordinaryPropertyAssignments: OrdinaryPropertyAssignments = new Map();
+    for(const [name, val] of props) {
+      if(RESERVED_NAMES.hasOwnProperty(name)) continue;
+      switch(val.kind) {
+        case ts.SyntaxKind.MethodDeclaration:
+          ordinaryMethods.set(name, val as ts.MethodDeclaration);
+          break;
+        case ts.SyntaxKind.ShorthandPropertyAssignment:
+          ordinaryShorthandProperties.set(name, val as ts.ShorthandPropertyAssignment);
+          break;
+        case ts.SyntaxKind.GetAccessor:
+          ordinaryGetAccessors.set(name, val as ts.GetAccessorDeclaration);
+          break;
+        case ts.SyntaxKind.PropertyAssignment:
+          ordinaryPropertyAssignments.set(name, val as ts.PropertyAssignment);
+          break;
+        default:
+          throw new Error(`Unsupported element kind: ${ts.SyntaxKind[val.kind]}`);
+      }
+      //ordinaryMethods.set(name, tsUtils.assertNodeKind(val, ts.SyntaxKind.MethodDeclaration) as ts.MethodDeclaration);
+    }
+
+    const eventsComments: string[] = this.getEventsComments(info.getFullText());
+
+    return {
+      reservedDeclarations: {
+        is: this.getStringLiteralValueWithComments(this.getLegacyPropertyInitializer(props, "is")),
+        _legacyUndefinedCheck: this.getBooleanLiteralValueWithComments(this.getLegacyPropertyInitializer(props, "_legacyUndefinedCheck")),
+        properties: this.getObjectLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "properties")),
+        behaviors: this.getArrayLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "behaviors")),
+        observers: this.getArrayLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "observers")),
+        listeners: this.getObjectLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "listeners")),
+        hostAttributes: this.getObjectLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "hostAttributes")),
+        keyBindings: this.getObjectLiteralExpressionWithComments(this.getLegacyPropertyInitializer(props, "keyBindings")),
+      },
+      eventsComments: eventsComments,
+      lifecycleMethods: legacyLifecycleMethods,
+      ordinaryMethods: ordinaryMethods,
+      ordinaryShorthandProperties: ordinaryShorthandProperties,
+      ordinaryGetAccessors: ordinaryGetAccessors,
+      ordinaryPropertyAssignments: ordinaryPropertyAssignments,
+    };
+  }
+
+  private convertLegacyProeprtyInitializer<T>(initializer: LegacyPropertyInitializer | undefined, converter: (exp: ts.Expression) => T): DataWithComments<T> | undefined {
+    if(!initializer) {
+      return undefined;
+    }
+    return {
+      data: converter(initializer.data),
+      leadingComments: initializer.leadingComments,
+    }
+  }
+
+  private getObjectLiteralExpressionWithComments(initializer: LegacyPropertyInitializer | undefined): DataWithComments<ts.ObjectLiteralExpression> | undefined {
+    return this.convertLegacyProeprtyInitializer(initializer,
+        expr => codeUtils.getObjectLiteralExpression(expr));
+  }
+
+  private getStringLiteralValueWithComments(initializer: LegacyPropertyInitializer | undefined): DataWithComments<string> | undefined {
+    return this.convertLegacyProeprtyInitializer(initializer,
+        expr => codeUtils.getStringLiteralValue(expr));
+  }
+
+  private getBooleanLiteralValueWithComments(initializer: LegacyPropertyInitializer | undefined): DataWithComments<boolean> | undefined {
+    return this.convertLegacyProeprtyInitializer(initializer,
+        expr => codeUtils.getBooleanLiteralValue(expr));
+  }
+
+
+  private getArrayLiteralExpressionWithComments(initializer: LegacyPropertyInitializer | undefined): DataWithComments<ts.ArrayLiteralExpression> | undefined {
+    return this.convertLegacyProeprtyInitializer(initializer,
+        expr => codeUtils.getArrayLiteralExpression(expr));
+  }
+
+  private getLegacyPropertyInitializer(props: Map<String, ts.ObjectLiteralElementLike>, propName: string): LegacyPropertyInitializer | undefined {
+    const property = props.get(propName);
+    if (!property) {
+      return undefined;
+    }
+    const assignment = codeUtils.getPropertyAssignment(property);
+    if (!assignment) {
+      return undefined;
+    }
+    const comments: string[] = codeUtils.getLeadingComments(property)
+          .filter(c => !this.isEventComment(c));
+    return {
+      data: assignment.initializer,
+      leadingComments: comments,
+    };
+  }
+
+  private isEventComment(comment: string): boolean {
+    return comment.indexOf('@event') >= 0;
+  }
+
+  private getEventsComments(polymerComponentSource: string): string[] {
+    return CommentsParser.collectAllComments(polymerComponentSource)
+        .filter(c => this.isEventComment(c));
+  }
+
+  private getLegacyMethodDeclaration(props: Map<String, ts.ObjectLiteralElementLike>, propName: string): ts.MethodDeclaration | undefined {
+    const property = props.get(propName);
+    if (!property) {
+      return undefined;
+    }
+    return codeUtils.assertNodeKind(property, ts.SyntaxKind.MethodDeclaration) as ts.MethodDeclaration;
+  }
+
+}
+
+export type ParsedPolymerComponent = LegacyPolymerComponent;
+
+export interface LegacyPolymerComponent {
+  jsFile: string;
+  htmlFile: string;
+  parsedFile: ts.SourceFile;
+  polymerFuncCallExpr: ts.CallExpression;
+  componentSettings: LegacyPolymerComponentSettings;
+}
+
+export interface LegacyReservedDeclarations {
+  is?: DataWithComments<string>;
+  _legacyUndefinedCheck?: DataWithComments<boolean>;
+  properties?: DataWithComments<ts.ObjectLiteralExpression>;
+  behaviors?: DataWithComments<ts.ArrayLiteralExpression>,
+  observers? :DataWithComments<ts.ArrayLiteralExpression>,
+  listeners? :DataWithComments<ts.ObjectLiteralExpression>,
+  hostAttributes?: DataWithComments<ts.ObjectLiteralExpression>,
+  keyBindings?: DataWithComments<ts.ObjectLiteralExpression>,
+}
+
+export const LegacyLifecycleMethodsArray = <const>["beforeRegister", "registered", "created", "ready", "attached" , "detached", "attributeChanged"];
+export type LegacyLifecycleMethodName = typeof LegacyLifecycleMethodsArray[number];
+export type LegacyLifecycleMethods = Map<LegacyLifecycleMethodName, ts.MethodDeclaration>;
+export type OrdinaryMethods = Map<string, ts.MethodDeclaration>;
+export type OrdinaryShorthandProperties = Map<string, ts.ShorthandPropertyAssignment>;
+export type OrdinaryGetAccessors = Map<string, ts.GetAccessorDeclaration>;
+export type OrdinaryPropertyAssignments = Map<string, ts.PropertyAssignment>;
+export type ReservedName = LegacyLifecycleMethodName | keyof LegacyReservedDeclarations;
+export const RESERVED_NAMES: {[x in ReservedName]: boolean} = {
+  attached: true,
+  detached: true,
+  ready: true,
+  created: true,
+  beforeRegister: true,
+  registered: true,
+  attributeChanged: true,
+  is: true,
+  _legacyUndefinedCheck: true,
+  properties: true,
+  behaviors: true,
+  observers: true,
+  listeners: true,
+  hostAttributes: true,
+  keyBindings: true,
+};
+
+export interface LegacyPolymerComponentSettings {
+  reservedDeclarations: LegacyReservedDeclarations;
+  lifecycleMethods: LegacyLifecycleMethods,
+  ordinaryMethods: OrdinaryMethods,
+  ordinaryShorthandProperties: OrdinaryShorthandProperties,
+  ordinaryGetAccessors: OrdinaryGetAccessors,
+  ordinaryPropertyAssignments: OrdinaryPropertyAssignments,
+  eventsComments: string[];
+}
+
+export interface DataWithComments<T> {
+  data: T;
+  leadingComments: string[];
+}
+
+type LegacyPropertyInitializer = DataWithComments<ts.Expression>;
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/polymerElementBuilder.ts b/tools/polygerrit-updater/src/funcToClassConversion/polymerElementBuilder.ts
new file mode 100644
index 0000000..d6e113c
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/polymerElementBuilder.ts
@@ -0,0 +1,142 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import {DataWithComments, LegacyPolymerComponent, LegacyReservedDeclarations, OrdinaryGetAccessors, OrdinaryMethods, OrdinaryPropertyAssignments, OrdinaryShorthandProperties} from './polymerComponentParser';
+import * as ts from 'typescript';
+import * as codeUtils from '../utils/codeUtils';
+import {LifecycleMethod} from './lifecycleMethodsBuilder';
+import {PolymerClassBuilder} from '../utils/polymerClassBuilder';
+import {SyntaxKind} from 'typescript';
+
+export interface ClassBasedPolymerElement {
+  classDeclaration: ts.ClassDeclaration;
+  componentRegistration: ts.ExpressionStatement;
+  eventsComments: string[];
+  generatedComments: string[];
+}
+
+export class PolymerElementBuilder {
+  private readonly reservedDeclarations: LegacyReservedDeclarations;
+  private readonly classBuilder: PolymerClassBuilder;
+  private mixins: ts.ExpressionWithTypeArguments | null;
+
+  public constructor(private readonly legacyComponent: LegacyPolymerComponent, className: string) {
+    this.reservedDeclarations = legacyComponent.componentSettings.reservedDeclarations;
+    this.classBuilder = new PolymerClassBuilder(className);
+    this.mixins = null;
+  }
+
+  public addIsAccessor(tagName: string) {
+    this.classBuilder.addIsAccessor(this.createIsAccessor(tagName));
+  }
+
+  public addPolymerPropertiesAccessor(legacyProperties: DataWithComments<ts.ObjectLiteralExpression>) {
+    const returnStatement = ts.createReturn(legacyProperties.data);
+    const block = ts.createBlock([returnStatement]);
+    let propertiesAccessor = ts.createGetAccessor(undefined, [ts.createModifier(ts.SyntaxKind.StaticKeyword)], "properties", [], undefined, block);
+    if(legacyProperties.leadingComments.length > 0) {
+      propertiesAccessor = codeUtils.restoreLeadingComments(propertiesAccessor, legacyProperties.leadingComments);
+    }
+    this.classBuilder.addPolymerPropertiesAccessor(legacyProperties.data.pos, propertiesAccessor);
+  }
+
+  public addPolymerPropertiesObservers(legacyObservers: ts.ArrayLiteralExpression) {
+    const returnStatement = ts.createReturn(legacyObservers);
+    const block = ts.createBlock([returnStatement]);
+    const propertiesAccessor = ts.createGetAccessor(undefined, [ts.createModifier(ts.SyntaxKind.StaticKeyword)], "observers", [], undefined, block);
+
+    this.classBuilder.addPolymerObserversAccessor(legacyObservers.pos, propertiesAccessor);
+  }
+
+  public addKeyBindings(keyBindings: ts.ObjectLiteralExpression) {
+    //In Polymer 2 keyBindings must be a property with get accessor
+    const returnStatement = ts.createReturn(keyBindings);
+    const block = ts.createBlock([returnStatement]);
+    const keyBindingsAccessor = ts.createGetAccessor(undefined, [], "keyBindings", [], undefined, block);
+
+    this.classBuilder.addGetAccessor(keyBindings.pos, keyBindingsAccessor);
+  }
+  public addOrdinaryMethods(ordinaryMethods: OrdinaryMethods) {
+    for(const [name, method] of ordinaryMethods) {
+      this.classBuilder.addMethod(method.pos, method);
+    }
+  }
+
+  public addOrdinaryGetAccessors(ordinaryGetAccessors: OrdinaryGetAccessors) {
+    for(const [name, accessor] of ordinaryGetAccessors) {
+      this.classBuilder.addGetAccessor(accessor.pos, accessor);
+    }
+  }
+
+  public addOrdinaryShorthandProperties(ordinaryShorthandProperties: OrdinaryShorthandProperties) {
+    for (const [name, property] of ordinaryShorthandProperties) {
+      this.classBuilder.addClassFieldInitializer(property.name, property.name);
+    }
+  }
+
+  public addOrdinaryPropertyAssignments(ordinaryPropertyAssignments: OrdinaryPropertyAssignments) {
+    for (const [name, property] of ordinaryPropertyAssignments) {
+      const propertyName = codeUtils.assertNodeKind(property.name, ts.SyntaxKind.Identifier) as ts.Identifier;
+      this.classBuilder.addClassFieldInitializer(propertyName, property.initializer);
+    }
+  }
+
+  public addMixin(name: string, mixinArguments?: ts.Expression[]) {
+    let fullMixinArguments: ts.Expression[] = [];
+    if(mixinArguments) {
+      fullMixinArguments.push(...mixinArguments);
+    }
+    if(this.mixins) {
+      fullMixinArguments.push(this.mixins.expression);
+    }
+    if(fullMixinArguments.length > 0) {
+      this.mixins = ts.createExpressionWithTypeArguments([], ts.createCall(codeUtils.createNameExpression(name), [], fullMixinArguments.length > 0 ? fullMixinArguments : undefined));
+    }
+    else {
+      this.mixins = ts.createExpressionWithTypeArguments([], codeUtils.createNameExpression(name));
+    }
+  }
+
+  public addClassJSDocComments(lines: string[]) {
+    this.classBuilder.addClassJSDocComments(lines);
+  }
+
+  public build(): ClassBasedPolymerElement {
+    if(this.mixins) {
+      this.classBuilder.setBaseType(this.mixins);
+    }
+    const className = this.classBuilder.className;
+    const callExpression = ts.createCall(ts.createPropertyAccess(ts.createIdentifier("customElements"), "define"), undefined, [ts.createPropertyAccess(ts.createIdentifier(className), "is"), ts.createIdentifier(className)]);
+    const classBuilderResult = this.classBuilder.build();
+    return {
+      classDeclaration: classBuilderResult.classDeclaration,
+      generatedComments: classBuilderResult.generatedComments,
+      componentRegistration: ts.createExpressionStatement(callExpression),
+      eventsComments: this.legacyComponent.componentSettings.eventsComments,
+    };
+  }
+
+  private createIsAccessor(tagName: string): ts.GetAccessorDeclaration {
+    const returnStatement = ts.createReturn(ts.createStringLiteral(tagName));
+    const block = ts.createBlock([returnStatement]);
+    const accessor = ts.createGetAccessor([], [ts.createModifier(ts.SyntaxKind.StaticKeyword)], "is", [], undefined, block);
+    return codeUtils.addReplacableCommentAfterNode(accessor, "eventsComments");
+  }
+
+  public addLifecycleMethods(newLifecycleMethods: LifecycleMethod[]) {
+    for(const lifecycleMethod of newLifecycleMethods) {
+      this.classBuilder.addLifecycleMethod(lifecycleMethod.name, lifecycleMethod.originalPos, lifecycleMethod.method);
+    }
+  }
+}
diff --git a/tools/polygerrit-updater/src/funcToClassConversion/updatedFileWriter.ts b/tools/polygerrit-updater/src/funcToClassConversion/updatedFileWriter.ts
new file mode 100644
index 0000000..a147f50
--- /dev/null
+++ b/tools/polygerrit-updater/src/funcToClassConversion/updatedFileWriter.ts
@@ -0,0 +1,248 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import {LegacyPolymerComponent} from './polymerComponentParser';
+import * as ts from 'typescript';
+import * as codeUtils from '../utils/codeUtils';
+import * as path from "path";
+import * as fs from "fs";
+import {LegacyPolymerFuncReplaceResult} from './legacyPolymerFuncReplacer';
+import {CommentsParser} from '../utils/commentsParser';
+
+export interface UpdatedFileWriterParameters {
+  out: string;
+  inplace: boolean;
+  writeOutput: boolean;
+  rootDir: string;
+}
+
+interface Replacement {
+  start: number;
+  length: number;
+  newText: string;
+}
+
+const elementRegistrationRegex = /^(\s*)customElements.define\((\w+).is, \w+\);$/m;
+const maxLineLength = 80;
+
+export class UpdatedFileWriter {
+  public constructor(private readonly component: LegacyPolymerComponent, private readonly params: UpdatedFileWriterParameters) {
+  }
+
+  public write(replaceResult: LegacyPolymerFuncReplaceResult, eventsComments: string[], generatedComments: string[]) {
+    const options: ts.PrinterOptions = {
+      removeComments: false,
+      newLine: ts.NewLineKind.LineFeed,
+    };
+    const printer = ts.createPrinter(options);
+    let newContent = codeUtils.applyNewLines(printer.printFile(replaceResult.file));
+    //ts printer doesn't keep original formatting of the file (spacing, new lines, comments, etc...).
+    //The following code tries restore original formatting
+
+    const existingComments = this.collectAllComments(newContent, []);
+
+    newContent = this.restoreEventsComments(newContent, eventsComments, existingComments);
+    newContent = this.restoreLeadingComments(newContent, replaceResult.leadingComments);
+    newContent = this.restoreFormating(printer, newContent);
+    newContent = this.splitLongLines(newContent);
+    newContent = this.addCommentsWarnings(newContent, generatedComments);
+
+    if (this.params.writeOutput) {
+      const outDir = this.params.inplace ? this.params.rootDir : this.params.out;
+      const fullOutPath = path.resolve(outDir, this.component.jsFile);
+      const fullOutDir = path.dirname(fullOutPath);
+      if (!fs.existsSync(fullOutDir)) {
+        fs.mkdirSync(fullOutDir, {
+          recursive: true,
+          mode: fs.lstatSync(this.params.rootDir).mode
+        });
+      }
+      fs.writeFileSync(fullOutPath, newContent);
+    }
+  }
+
+  private restoreEventsComments(content: string, eventsComments: string[], existingComments: Map<string, number>): string {
+    //In some cases Typescript compiler keep existing comments. These comments
+    // must not be restored here
+    eventsComments = eventsComments.filter(c => !existingComments.has(this.getNormalizedComment(c)));
+    return codeUtils.replaceComment(content, "eventsComments", "\n" + eventsComments.join("\n\n") + "\n");
+  }
+
+  private restoreLeadingComments(content: string, leadingComments: string[]): string {
+    return leadingComments.reduce(
+        (newContent, comment, commentIndex) =>
+            codeUtils.replaceComment(newContent, String(commentIndex), comment),
+        content);
+  }
+
+  private restoreFormating(printer: ts.Printer, newContent: string): string {
+    const originalFile = this.component.parsedFile;
+    const newFile = ts.createSourceFile(originalFile.fileName, newContent, originalFile.languageVersion, true, ts.ScriptKind.JS);
+    const textMap = new Map<ts.SyntaxKind, Map<string, Set<string>>>();
+    const comments = new Set<string>();
+    this.collectAllStrings(printer, originalFile, textMap);
+
+    const replacements: Replacement[] = [];
+    this.collectReplacements(printer, newFile, textMap, replacements);
+    replacements.sort((a, b) => b.start - a.start);
+    let result = newFile.getFullText();
+    let prevReplacement: Replacement | null = null;
+    for (const replacement of replacements) {
+      if (prevReplacement) {
+        if (replacement.start + replacement.length > prevReplacement.start) {
+          throw new Error('Internal error! Replacements must not intersect');
+        }
+      }
+      result = result.substring(0, replacement.start) + replacement.newText + result.substring(replacement.start + replacement.length);
+      prevReplacement = replacement;
+    }
+    return result;
+  }
+
+  private splitLongLines(content: string): string {
+    content = content.replace(elementRegistrationRegex, (match, indent, className) => {
+      if (match.length > maxLineLength) {
+        return `${indent}customElements.define(${className}.is,\n` +
+            `${indent}  ${className});`;
+      }
+      else {
+        return match;
+      }
+    });
+
+    return content
+        .replace(
+            "Polymer.LegacyDataMixin(Polymer.GestureEventListeners(Polymer.LegacyElementMixin(Polymer.Element)))",
+            "Polymer.LegacyDataMixin(\nPolymer.GestureEventListeners(\nPolymer.LegacyElementMixin(\nPolymer.Element)))")
+        .replace(
+            "Polymer.GestureEventListeners(Polymer.LegacyElementMixin(Polymer.Element))",
+            "Polymer.GestureEventListeners(\nPolymer.LegacyElementMixin(\nPolymer.Element))");
+
+  }
+
+  private addCommentsWarnings(newContent: string, generatedComments: string[]): string {
+    const expectedComments = this.collectAllComments(this.component.parsedFile.getFullText(), generatedComments);
+    const newComments = this.collectAllComments(newContent, []);
+    const commentsWarnings = [];
+    for (const [text, count] of expectedComments) {
+      const newCount = newComments.get(text);
+      if (!newCount) {
+        commentsWarnings.push(`Comment '${text}' is missing in the new content.`);
+      }
+      else if (newCount != count) {
+        commentsWarnings.push(`Comment '${text}' appears ${newCount} times in the new file and ${count} times in the old file.`);
+      }
+    }
+
+    for (const [text, newCount] of newComments) {
+      if (!expectedComments.has(text)) {
+        commentsWarnings.push(`Comment '${text}' appears only in the new content`);
+      }
+    }
+    if (commentsWarnings.length === 0) {
+      return newContent;
+    }
+    let commentsProblemStr = "";
+    if (commentsWarnings.length > 0) {
+      commentsProblemStr = commentsWarnings.join("-----------------------------\n");
+      console.log(commentsProblemStr);
+    }
+
+    return "//This file has the following problems with comments:\n" + commentsProblemStr + "\n" + newContent;
+
+  }
+
+  private collectAllComments(content: string, additionalComments: string[]): Map<string, number> {
+    const comments = CommentsParser.collectAllComments(content);
+    comments.push(...additionalComments);
+    const result = new Map<string, number>();
+    for (const comment of comments) {
+      let normalizedComment = this.getNormalizedComment(comment);
+      const count = result.get(normalizedComment);
+      if (count) {
+        result.set(normalizedComment, count + 1);
+      } else {
+        result.set(normalizedComment, 1);
+      }
+    }
+    return result;
+  }
+
+  private getNormalizedComment(comment: string): string {
+    if(comment.startsWith('/**')) {
+      comment = comment.replace(/^\s+\*/gm, "*");
+    }
+    return comment;
+  }
+
+  private collectAllStrings(printer: ts.Printer, node: ts.Node, map: Map<ts.SyntaxKind, Map<string, Set<string>>>) {
+    const formattedText = printer.printNode(ts.EmitHint.Unspecified, node, node.getSourceFile())
+    const originalText = node.getFullText();
+    this.addIfNotExists(map, node.kind, formattedText, originalText);
+    ts.forEachChild(node, child => this.collectAllStrings(printer, child, map));
+  }
+
+  private collectReplacements(printer: ts.Printer, node: ts.Node, map: Map<ts.SyntaxKind, Map<string, Set<string>>>, replacements: Replacement[]) {
+    if(node.kind === ts.SyntaxKind.ThisKeyword || node.kind === ts.SyntaxKind.Identifier || node.kind === ts.SyntaxKind.StringLiteral || node.kind === ts.SyntaxKind.NumericLiteral) {
+      return;
+    }
+    const replacement = this.getReplacement(printer, node, map);
+    if(replacement) {
+      replacements.push(replacement);
+      return;
+    }
+    ts.forEachChild(node, child => this.collectReplacements(printer, child, map, replacements));
+  }
+
+  private addIfNotExists(map: Map<ts.SyntaxKind, Map<string, Set<string>>>, kind: ts.SyntaxKind, formattedText: string, originalText: string) {
+    let mapForKind = map.get(kind);
+    if(!mapForKind) {
+      mapForKind = new Map();
+      map.set(kind, mapForKind);
+    }
+
+    let existingOriginalText = mapForKind.get(formattedText);
+    if(!existingOriginalText) {
+      existingOriginalText = new Set<string>();
+      mapForKind.set(formattedText, existingOriginalText);
+      //throw new Error(`Different formatting of the same string exists. Kind: ${ts.SyntaxKind[kind]}.\nFormatting 1:\n${originalText}\nFormatting2:\n${existingOriginalText}\n `);
+    }
+    existingOriginalText.add(originalText);
+  }
+
+  private getReplacement(printer: ts.Printer, node: ts.Node, map: Map<ts.SyntaxKind, Map<string, Set<string>>>): Replacement | undefined {
+    const replacementsForKind = map.get(node.kind);
+    if(!replacementsForKind) {
+      return;
+    }
+    // Use printer instead of getFullText to "isolate" node content.
+    // node.getFullText returns text with indents from the original file.
+    const newText = printer.printNode(ts.EmitHint.Unspecified, node, node.getSourceFile());
+    const originalSet = replacementsForKind.get(newText);
+    if(!originalSet || originalSet.size === 0) {
+      return;
+    }
+    if(originalSet.size >= 2) {
+      console.log(`Multiple replacements possible. Formatting of some lines can be changed`);
+    }
+    const replacementText: string = originalSet.values().next().value;
+    const nodeText = node.getFullText();
+    return {
+      start: node.pos,
+      length: nodeText.length,//Do not use newText here!
+      newText: replacementText,
+    }
+  }
+
+}
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/index.ts b/tools/polygerrit-updater/src/index.ts
new file mode 100644
index 0000000..1b7c315
--- /dev/null
+++ b/tools/polygerrit-updater/src/index.ts
@@ -0,0 +1,168 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as fs from "fs";
+import * as path from "path";
+import {LegacyPolymerComponent, LegacyPolymerComponentParser} from './funcToClassConversion/polymerComponentParser';
+import {ClassBasedPolymerElement} from './funcToClassConversion/polymerElementBuilder';
+import {PolymerFuncToClassBasedConverter} from './funcToClassConversion/funcToClassBasedElementConverter';
+import {LegacyPolymerFuncReplacer} from './funcToClassConversion/legacyPolymerFuncReplacer';
+import {UpdatedFileWriter} from './funcToClassConversion/updatedFileWriter';
+import {CommandLineParser} from './utils/commandLineParser';
+
+interface UpdaterParameters {
+  htmlFiles: Set<string>;
+  jsFiles: Set<string>;
+  out: string;
+  inplace: boolean;
+  writeOutput: boolean;
+  rootDir: string;
+}
+
+interface InputFilesFilter {
+  includeDir(path: string): boolean;
+  includeFile(path: string): boolean;
+}
+
+function addFile(filePath: string, params: UpdaterParameters, filter: InputFilesFilter) {
+  const parsedPath = path.parse(filePath);
+  const ext = parsedPath.ext.toLowerCase();
+  const relativePath = path.relative(params.rootDir, filePath);
+  if(!filter.includeFile(relativePath)) return;
+  if(relativePath.startsWith("../")) {
+    throw new Error(`${filePath} is not in rootDir ${params.rootDir}`);
+  }
+  if(ext === ".html") {
+    params.htmlFiles.add(relativePath);
+  } if(ext === ".js") {
+    params.jsFiles.add(relativePath);
+  }
+}
+
+function addDirectory(dirPath: string, params: UpdaterParameters, recursive: boolean, filter: InputFilesFilter): void {
+  const entries = fs.readdirSync(dirPath, {withFileTypes: true});
+  for(const entry of entries) {
+    const dirEnt = entry as fs.Dirent;
+    const fullPath = path.join(dirPath, dirEnt.name);
+    const relativePath = path.relative(params.rootDir, fullPath);
+    if(dirEnt.isDirectory()) {
+      if (!filter.includeDir(relativePath)) continue;
+      if(recursive) {
+        addDirectory(fullPath, params, recursive, filter);
+      }
+    }
+    else if(dirEnt.isFile()) {
+      addFile(fullPath, params, filter);
+    } else {
+      throw Error(`Unsupported dir entry '${entry.name}' in '${fullPath}'`);
+    }
+  }
+}
+
+async function updateLegacyComponent(component: LegacyPolymerComponent, params: UpdaterParameters) {
+  const classBasedElement: ClassBasedPolymerElement = PolymerFuncToClassBasedConverter.convert(component);
+
+  const replacer = new LegacyPolymerFuncReplacer(component);
+  const replaceResult = replacer.replace(classBasedElement);
+  try {
+    const writer = new UpdatedFileWriter(component, params);
+    writer.write(replaceResult, classBasedElement.eventsComments, classBasedElement.generatedComments);
+  }
+  finally {
+    replaceResult.dispose();
+  }
+}
+
+async function main() {
+  const params: UpdaterParameters = await getParams();
+  if(params.jsFiles.size === 0) {
+    console.log("No files found");
+    return;
+  }
+  const legacyPolymerComponentParser = new LegacyPolymerComponentParser(params.rootDir, params.htmlFiles)
+  for(const jsFile of params.jsFiles) {
+    console.log(`Processing ${jsFile}`);
+    const legacyComponent = await legacyPolymerComponentParser.parse(jsFile);
+    if(legacyComponent) {
+      await updateLegacyComponent(legacyComponent, params);
+      continue;
+    }
+  }
+}
+
+interface CommandLineParameters {
+  src: string[];
+  recursive: boolean;
+  excludes: string[];
+  out: string;
+  inplace: boolean;
+  noOutput: boolean;
+  rootDir: string;
+}
+
+async function getParams(): Promise<UpdaterParameters> {
+  const parser = new CommandLineParser({
+    src: CommandLineParser.createStringArrayOption("src", ".js file or folder to process", []),
+    recursive: CommandLineParser.createBooleanOption("r", "process folder recursive", false),
+    excludes: CommandLineParser.createStringArrayOption("exclude", "List of file prefixes to exclude. If relative file path starts with one of the prefixes, it will be excluded", []),
+    out: CommandLineParser.createStringOption("out", "Output folder.", null),
+    rootDir: CommandLineParser.createStringOption("root", "Root directory for src files", "/"),
+    inplace: CommandLineParser.createBooleanOption("i", "Update files inplace", false),
+    noOutput: CommandLineParser.createBooleanOption("noout", "Do everything, but do not write anything to files", false),
+  });
+  const commandLineParams: CommandLineParameters = parser.parse(process.argv) as CommandLineParameters;
+
+  const params: UpdaterParameters = {
+    htmlFiles: new Set(),
+    jsFiles: new Set(),
+    writeOutput: !commandLineParams.noOutput,
+    inplace: commandLineParams.inplace,
+    out: commandLineParams.out,
+    rootDir: path.resolve(commandLineParams.rootDir)
+  };
+
+  if(params.writeOutput && !params.inplace && !params.out) {
+    throw new Error("You should specify output directory (--out directory_name)");
+  }
+
+  const filter = new ExcludeFilesFilter(commandLineParams.excludes);
+  for(const srcPath of commandLineParams.src) {
+    const resolvedPath = path.resolve(params.rootDir, srcPath);
+    if(fs.lstatSync(resolvedPath).isFile()) {
+      addFile(resolvedPath, params, filter);
+    } else {
+      addDirectory(resolvedPath, params, commandLineParams.recursive, filter);
+    }
+  }
+  return params;
+}
+
+class ExcludeFilesFilter implements InputFilesFilter {
+  public constructor(private readonly excludes: string[]) {
+  }
+  includeDir(path: string): boolean {
+    return this.excludes.every(exclude => !path.startsWith(exclude));
+  }
+
+  includeFile(path: string): boolean {
+    return this.excludes.every(exclude => !path.startsWith(exclude));
+  }
+}
+
+main().then(() => {
+  process.exit(0);
+}).catch(e => {
+  console.error(e);
+  process.exit(1);
+});
diff --git a/tools/polygerrit-updater/src/utils/codeUtils.ts b/tools/polygerrit-updater/src/utils/codeUtils.ts
new file mode 100644
index 0000000..53a7f0d
--- /dev/null
+++ b/tools/polygerrit-updater/src/utils/codeUtils.ts
@@ -0,0 +1,183 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as ts from 'typescript';
+import {SyntaxKind} from 'typescript';
+import {Node} from 'typescript';
+
+export function assertNodeKind<T extends U, U extends ts.Node>(node: U, expectedKind: ts.SyntaxKind): T {
+  if (node.kind !== expectedKind) {
+    throw new Error(`Invlid node kind. Expected: ${ts.SyntaxKind[expectedKind]}, actual: ${ts.SyntaxKind[node.kind]}`);
+  }
+  return node as T;
+}
+
+export function assertNodeKindOrUndefined<T extends U, U extends ts.Node>(node: U | undefined, expectedKind: ts.SyntaxKind): T | undefined {
+  if (!node) {
+    return undefined;
+  }
+  return assertNodeKind<T, U>(node, expectedKind);
+}
+
+export function getPropertyAssignment(expression?: ts.ObjectLiteralElementLike): ts.PropertyAssignment | undefined {
+  return assertNodeKindOrUndefined(expression, ts.SyntaxKind.PropertyAssignment);
+}
+
+export function getStringLiteralValue(expression: ts.Expression): string {
+  const literal: ts.StringLiteral = assertNodeKind(expression, ts.SyntaxKind.StringLiteral);
+  return literal.text;
+}
+
+export function getBooleanLiteralValue(expression: ts.Expression): boolean {
+  if (expression.kind === ts.SyntaxKind.TrueKeyword) {
+    return true;
+  }
+  if (expression.kind === ts.SyntaxKind.FalseKeyword) {
+    return false;
+  }
+  throw new Error(`Invalid expression kind - ${expression.kind}`);
+}
+
+export function getObjectLiteralExpression(expression: ts.Expression): ts.ObjectLiteralExpression {
+  return assertNodeKind(expression, ts.SyntaxKind.ObjectLiteralExpression);
+}
+
+export function getArrayLiteralExpression(expression: ts.Expression): ts.ArrayLiteralExpression {
+  return assertNodeKind(expression, ts.SyntaxKind.ArrayLiteralExpression);
+}
+
+export function replaceNode(file: ts.SourceFile, originalNode: ts.Node, newNode: ts.Node): ts.TransformationResult<ts.SourceFile> {
+  const nodeReplacerTransformer: ts.TransformerFactory<ts.SourceFile> = (context: ts.TransformationContext) => {
+    const visitor: ts.Visitor = (node) => {
+      if(node === originalNode) {
+        return newNode;
+      }
+      return ts.visitEachChild(node, visitor, context);
+    };
+
+
+    return source => ts.visitNode(source, visitor);
+  };
+  return ts.transform(file, [nodeReplacerTransformer]);
+}
+
+export type NameExpression = ts.Identifier | ts.ThisExpression | ts.PropertyAccessExpression;
+export function createNameExpression(fullPath: string): NameExpression {
+  const parts = fullPath.split(".");
+  let result: NameExpression = parts[0] === "this" ? ts.createThis() : ts.createIdentifier(parts[0]);
+  for(let i = 1; i < parts.length; i++) {
+    result = ts.createPropertyAccess(result, parts[i]);
+  }
+  return result;
+}
+
+const generatedCommentNewLineAfterText = "-Generated code - new line after - 9cb292bc-5d88-4c5e-88f4-49535c93beb9 -";
+const generatedCommentNewLineBeforeText = "-Generated code - new line-before - 9cb292bc-5d88-4c5e-88f4-49535c93beb9 -";
+const generatedCommentNewLineAfterRegExp = new RegExp("//" + generatedCommentNewLineAfterText, 'g');
+const generatedCommentNewLineBeforeRegExp = new RegExp("//" + generatedCommentNewLineBeforeText + "\n", 'g');
+const replacableCommentText = "- Replacepoint - 9cb292bc-5d88-4c5e-88f4-49535c93beb9 -";
+
+export function addNewLineAfterNode<T extends ts.Node>(node: T): T {
+  const comment = ts.getSyntheticTrailingComments(node);
+  if(comment && comment.some(c => c.text === generatedCommentNewLineAfterText)) {
+    return node;
+  }
+  return ts.addSyntheticTrailingComment(node, ts.SyntaxKind.SingleLineCommentTrivia, generatedCommentNewLineAfterText, true);
+}
+
+export function addNewLineBeforeNode<T extends ts.Node>(node: T): T {
+  const comment = ts.getSyntheticLeadingComments(node);
+  if(comment && comment.some(c => c.text === generatedCommentNewLineBeforeText)) {
+    return node;
+  }
+  return ts.addSyntheticLeadingComment(node, ts.SyntaxKind.SingleLineCommentTrivia, generatedCommentNewLineBeforeText, true);
+}
+
+
+export function applyNewLines(text: string): string {
+  return text.replace(generatedCommentNewLineAfterRegExp, "").replace(generatedCommentNewLineBeforeRegExp, "");
+
+}
+export function addReplacableCommentAfterNode<T extends ts.Node>(node: T, name: string): T {
+  return ts.addSyntheticTrailingComment(node, ts.SyntaxKind.SingleLineCommentTrivia, replacableCommentText + name, true);
+}
+
+export function addReplacableCommentBeforeNode<T extends ts.Node>(node: T, name: string): T {
+  return ts.addSyntheticLeadingComment(node, ts.SyntaxKind.SingleLineCommentTrivia, replacableCommentText + name, true);
+}
+
+export function replaceComment(text: string, commentName: string, newContent: string): string {
+  return text.replace("//" + replacableCommentText + commentName, newContent);
+}
+
+export function createMethod(name: string, methodDecl: ts.MethodDeclaration | undefined, codeAtStart: ts.Statement[], codeAtEnd: ts.Statement[], callSuperMethod: boolean): ts.MethodDeclaration | undefined {
+  if(!methodDecl && (codeAtEnd.length > 0 || codeAtEnd.length > 0)) {
+    methodDecl = ts.createMethod([], [], undefined, name, undefined, [], [],undefined, ts.createBlock([]));
+  }
+  if(!methodDecl) {
+    return;
+  }
+  if (!methodDecl.body) {
+    throw new Error("Method must have a body");
+  }
+  if(methodDecl.parameters.length > 0) {
+    throw new Error("Methods with parameters are not supported");
+  }
+  let newStatements = [...codeAtStart];
+  if(callSuperMethod) {
+    const superCall: ts.CallExpression = ts.createCall(ts.createPropertyAccess(ts.createSuper(), assertNodeKind(methodDecl.name, ts.SyntaxKind.Identifier) as ts.Identifier), [], []);
+    const superCallExpression = ts.createExpressionStatement(superCall);
+    newStatements.push(superCallExpression);
+  }
+  newStatements.push(...codeAtEnd);
+  const newBody = ts.getMutableClone(methodDecl.body);
+
+  newStatements = newStatements.map(m => addNewLineAfterNode(m));
+  newStatements.splice(codeAtStart.length + 1, 0, ...newBody.statements);
+
+  newBody.statements = ts.createNodeArray(newStatements);
+
+  const newMethod = ts.getMutableClone(methodDecl);
+  newMethod.body = newBody;
+
+  return newMethod;
+}
+
+export function restoreLeadingComments<T extends Node>(node: T, originalComments: string[]): T {
+  if(originalComments.length === 0) {
+    return node;
+  }
+  for(const comment of originalComments) {
+    if(comment.startsWith("//")) {
+      node = ts.addSyntheticLeadingComment(node, SyntaxKind.SingleLineCommentTrivia, comment.substr(2), true);
+    } else if(comment.startsWith("/*")) {
+      if(!comment.endsWith("*/")) {
+        throw new Error(`Not support comment: ${comment}`);
+      }
+      node = ts.addSyntheticLeadingComment(node, SyntaxKind.MultiLineCommentTrivia, comment.substr(2, comment.length - 4), true);
+    } else {
+      throw new Error(`Not supported comment: ${comment}`);
+    }
+  }
+  return node;
+}
+
+export function getLeadingComments(node: ts.Node): string[] {
+  const nodeText = node.getFullText();
+  const commentRanges = ts.getLeadingCommentRanges(nodeText, 0);
+  if(!commentRanges) {
+    return [];
+  }
+  return commentRanges.map(range => nodeText.substring(range.pos, range.end))
+}
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/utils/commandLineParser.ts b/tools/polygerrit-updater/src/utils/commandLineParser.ts
new file mode 100644
index 0000000..658b7ff
--- /dev/null
+++ b/tools/polygerrit-updater/src/utils/commandLineParser.ts
@@ -0,0 +1,134 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed un  der the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+export class CommandLineParser {
+  public static createStringArrayOption(optionName: string, help: string, defaultValue: string[]): CommandLineArgument {
+    return new StringArrayOption(optionName, help, defaultValue);
+  }
+  public static createBooleanOption(optionName: string, help: string, defaultValue: boolean): CommandLineArgument {
+    return new BooleanOption(optionName, help, defaultValue);
+  }
+  public static createStringOption(optionName: string, help: string, defaultValue: string | null): CommandLineArgument {
+    return new StringOption(optionName, help, defaultValue);
+  }
+
+  public constructor(private readonly argumentTypes: {[name: string]: CommandLineArgument}) {
+  }
+  public parse(argv: string[]): object {
+    const result = Object.assign({});
+    let index = 2; //argv[0] - node interpreter, argv[1] - index.js
+    for(const argumentField in this.argumentTypes) {
+      result[argumentField] = this.argumentTypes[argumentField].getDefaultValue();
+    }
+    while(index < argv.length) {
+      let knownArgument = false;
+      for(const argumentField in this.argumentTypes) {
+        const argumentType = this.argumentTypes[argumentField];
+        const argumentValue = argumentType.tryRead(argv, index);
+        if(argumentValue) {
+          knownArgument = true;
+          index += argumentValue.consumed;
+          result[argumentField] = argumentValue.value;
+          break;
+        }
+      }
+      if(!knownArgument) {
+        throw new Error(`Unknown argument ${argv[index]}`);
+      }
+    }
+    return result;
+  }
+}
+
+interface CommandLineArgumentReadResult {
+  consumed: number;
+  value: any;
+}
+
+export interface CommandLineArgument {
+  getDefaultValue(): any;
+  tryRead(argv: string[], startIndex: number): CommandLineArgumentReadResult | null;
+}
+
+abstract class CommandLineOption implements CommandLineArgument {
+  protected constructor(protected readonly optionName: string, protected readonly help: string, private readonly defaultValue: any) {
+  }
+  public tryRead(argv: string[], startIndex: number): CommandLineArgumentReadResult | null  {
+    if(argv[startIndex] !== "--" + this.optionName) {
+      return null;
+    }
+    const readArgumentsResult = this.readArguments(argv, startIndex + 1);
+    if(!readArgumentsResult) {
+      return null;
+    }
+    readArgumentsResult.consumed++; // Add option name
+    return readArgumentsResult;
+  }
+  public getDefaultValue(): any {
+    return this.defaultValue;
+  }
+
+  protected abstract readArguments(argv: string[], startIndex: number) : CommandLineArgumentReadResult | null;
+}
+
+class StringArrayOption extends CommandLineOption {
+  public constructor(optionName: string, help: string, defaultValue: string[]) {
+    super(optionName, help, defaultValue);
+  }
+
+  protected readArguments(argv: string[], startIndex: number): CommandLineArgumentReadResult {
+    const result = [];
+    let index = startIndex;
+    while(index < argv.length) {
+      if(argv[index].startsWith("--")) {
+        break;
+      }
+      result.push(argv[index]);
+      index++;
+    }
+    return {
+      consumed: index - startIndex,
+      value: result
+    }
+  }
+}
+
+class BooleanOption extends CommandLineOption {
+  public constructor(optionName: string, help: string, defaultValue: boolean) {
+    super(optionName, help, defaultValue);
+  }
+
+  protected readArguments(argv: string[], startIndex: number): CommandLineArgumentReadResult {
+    return {
+      consumed: 0,
+      value: true
+    }
+  }
+}
+
+class StringOption extends CommandLineOption {
+  public constructor(optionName: string, help: string, defaultValue: string | null) {
+    super(optionName, help, defaultValue);
+  }
+
+  protected readArguments(argv: string[], startIndex: number): CommandLineArgumentReadResult | null {
+    if(startIndex >= argv.length) {
+      return null;
+    }
+    return {
+      consumed: 1,
+      value: argv[startIndex]
+    }
+  }
+}
diff --git a/tools/polygerrit-updater/src/utils/commentsParser.ts b/tools/polygerrit-updater/src/utils/commentsParser.ts
new file mode 100644
index 0000000..b849829
--- /dev/null
+++ b/tools/polygerrit-updater/src/utils/commentsParser.ts
@@ -0,0 +1,79 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+enum CommentScannerState {
+  Text,
+  SingleLineComment,
+  MultLineComment
+}
+export class CommentsParser {
+  public static collectAllComments(text: string): string[] {
+    const result: string[] = [];
+    let state = CommentScannerState.Text;
+    let pos = 0;
+    function readSingleLineComment() {
+      const startPos = pos;
+      while(pos < text.length && text[pos] !== '\n') {
+        pos++;
+      }
+      return text.substring(startPos, pos);
+    }
+    function readMultiLineComment() {
+      const startPos = pos;
+      while(pos < text.length) {
+        if(pos < text.length - 1 && text[pos] === '*' && text[pos + 1] === '/') {
+          pos += 2;
+          break;
+        }
+        pos++;
+      }
+      return text.substring(startPos, pos);
+    }
+
+    function skipString(lastChar: string) {
+      pos++;
+      while(pos < text.length) {
+        if(text[pos] === lastChar) {
+          pos++;
+          return;
+        } else if(text[pos] === '\\') {
+          pos+=2;
+          continue;
+        }
+        pos++;
+      }
+    }
+
+
+    while(pos < text.length - 1) {
+      if(text[pos] === '/' && text[pos + 1] === '/') {
+        result.push(readSingleLineComment());
+      } else if(text[pos] === '/' && text[pos + 1] === '*') {
+        result.push(readMultiLineComment());
+      } else if(text[pos] === "'") {
+        skipString("'");
+      } else if(text[pos] === '"') {
+        skipString('"');
+      } else if(text[pos] === '`') {
+        skipString('`');
+      } else if(text[pos] == '/') {
+        skipString('/');
+      } {
+        pos++;
+      }
+
+    }
+    return result;
+  }
+}
diff --git a/tools/polygerrit-updater/src/utils/polymerClassBuilder.ts b/tools/polygerrit-updater/src/utils/polymerClassBuilder.ts
new file mode 100644
index 0000000..b1a4320
--- /dev/null
+++ b/tools/polygerrit-updater/src/utils/polymerClassBuilder.ts
@@ -0,0 +1,270 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import * as ts from 'typescript';
+import * as codeUtils from './codeUtils';
+import {LegacyLifecycleMethodName, LegacyLifecycleMethodsArray} from '../funcToClassConversion/polymerComponentParser';
+import {SyntaxKind} from 'typescript';
+
+enum PolymerClassMemberType {
+  IsAccessor,
+  Constructor,
+  PolymerPropertiesAccessor,
+  PolymerObserversAccessor,
+  Method,
+  ExistingLifecycleMethod,
+  NewLifecycleMethod,
+  GetAccessor,
+}
+
+type PolymerClassMember = PolymerClassIsAccessor | PolymerClassConstructor | PolymerClassExistingLifecycleMethod | PolymerClassNewLifecycleMethod | PolymerClassSimpleMember;
+
+interface PolymerClassExistingLifecycleMethod {
+  member: ts.MethodDeclaration;
+  memberType: PolymerClassMemberType.ExistingLifecycleMethod;
+  name: string;
+  lifecycleOrder: number;
+  originalPos: number;
+}
+
+interface PolymerClassNewLifecycleMethod {
+  member: ts.MethodDeclaration;
+  memberType: PolymerClassMemberType.NewLifecycleMethod;
+  name: string;
+  lifecycleOrder: number;
+  originalPos: -1
+}
+
+interface PolymerClassIsAccessor {
+  member: ts.GetAccessorDeclaration;
+  memberType: PolymerClassMemberType.IsAccessor;
+  originalPos: -1
+}
+
+interface PolymerClassConstructor {
+  member: ts.ConstructorDeclaration;
+  memberType: PolymerClassMemberType.Constructor;
+  originalPos: -1
+}
+
+interface PolymerClassSimpleMember {
+  memberType: PolymerClassMemberType.PolymerPropertiesAccessor | PolymerClassMemberType.PolymerObserversAccessor | PolymerClassMemberType.Method | PolymerClassMemberType.GetAccessor;
+  member: ts.ClassElement;
+  originalPos: number;
+}
+
+export interface PolymerClassBuilderResult {
+  classDeclaration: ts.ClassDeclaration;
+  generatedComments: string[];
+}
+
+export class PolymerClassBuilder {
+  private readonly members: PolymerClassMember[] = [];
+  public readonly constructorStatements: ts.Statement[] = [];
+  private baseType: ts.ExpressionWithTypeArguments | undefined;
+  private classJsDocComments: string[];
+
+  public constructor(public readonly className: string) {
+    this.classJsDocComments = [];
+  }
+
+  public addIsAccessor(accessor: ts.GetAccessorDeclaration) {
+    this.members.push({
+      member: accessor,
+      memberType: PolymerClassMemberType.IsAccessor,
+      originalPos: -1
+    });
+  }
+
+  public addPolymerPropertiesAccessor(originalPos: number, accessor: ts.GetAccessorDeclaration) {
+    this.members.push({
+      member: accessor,
+      memberType: PolymerClassMemberType.PolymerPropertiesAccessor,
+      originalPos: originalPos
+    });
+  }
+
+  public addPolymerObserversAccessor(originalPos: number, accessor: ts.GetAccessorDeclaration) {
+    this.members.push({
+      member: accessor,
+      memberType: PolymerClassMemberType.PolymerObserversAccessor,
+      originalPos: originalPos
+    });
+  }
+
+
+  public addClassFieldInitializer(name: string | ts.Identifier, initializer: ts.Expression) {
+    const assignment = ts.createAssignment(ts.createPropertyAccess(ts.createThis(), name), initializer);
+    this.constructorStatements.push(codeUtils.addNewLineAfterNode(ts.createExpressionStatement(assignment)));
+  }
+  public addMethod(originalPos: number, method: ts.MethodDeclaration) {
+    this.members.push({
+      member: method,
+      memberType: PolymerClassMemberType.Method,
+      originalPos: originalPos
+    });
+  }
+
+  public addGetAccessor(originalPos: number, accessor: ts.GetAccessorDeclaration) {
+    this.members.push({
+      member: accessor,
+      memberType: PolymerClassMemberType.GetAccessor,
+      originalPos: originalPos
+    });
+  }
+
+  public addLifecycleMethod(name: LegacyLifecycleMethodName, originalPos: number, method: ts.MethodDeclaration) {
+    const lifecycleOrder = LegacyLifecycleMethodsArray.indexOf(name);
+    if(lifecycleOrder < 0) {
+      throw new Error(`Invalid lifecycle name`);
+    }
+    if(originalPos >= 0) {
+      this.members.push({
+        member: method,
+        memberType: PolymerClassMemberType.ExistingLifecycleMethod,
+        originalPos: originalPos,
+        name: name,
+        lifecycleOrder: lifecycleOrder
+      })
+    } else {
+      this.members.push({
+        member: method,
+        memberType: PolymerClassMemberType.NewLifecycleMethod,
+        name: name,
+        lifecycleOrder: lifecycleOrder,
+        originalPos: -1
+      })
+    }
+  }
+
+  public setBaseType(type: ts.ExpressionWithTypeArguments) {
+    if(this.baseType) {
+      throw new Error("Class can have only one base type");
+    }
+    this.baseType = type;
+  }
+
+  public build(): PolymerClassBuilderResult {
+    let heritageClauses: ts.HeritageClause[] = [];
+    if (this.baseType) {
+      const extendClause = ts.createHeritageClause(ts.SyntaxKind.ExtendsKeyword, [this.baseType]);
+      heritageClauses.push(extendClause);
+    }
+    const finalMembers: PolymerClassMember[] = [];
+    const isAccessors = this.members.filter(member => member.memberType === PolymerClassMemberType.IsAccessor);
+    if(isAccessors.length !== 1) {
+      throw new Error("Class must have exactly one 'is'");
+    }
+    finalMembers.push(isAccessors[0]);
+    const constructorMember = this.createConstructor();
+    if(constructorMember) {
+      finalMembers.push(constructorMember);
+    }
+
+    const newLifecycleMethods: PolymerClassNewLifecycleMethod[] = [];
+    this.members.forEach(member => {
+      if(member.memberType === PolymerClassMemberType.NewLifecycleMethod) {
+        newLifecycleMethods.push(member);
+      }
+    });
+
+    const methodsWithKnownPosition = this.members.filter(member => member.originalPos >= 0);
+    methodsWithKnownPosition.sort((a, b) => a.originalPos - b.originalPos);
+
+    finalMembers.push(...methodsWithKnownPosition);
+
+
+    for(const newLifecycleMethod of newLifecycleMethods) {
+      //Number of methods is small - use brute force solution
+      let closestNextIndex = -1;
+      let closestNextOrderDiff: number = LegacyLifecycleMethodsArray.length;
+      let closestPrevIndex = -1;
+      let closestPrevOrderDiff: number = LegacyLifecycleMethodsArray.length;
+      for (let i = 0; i < finalMembers.length; i++) {
+        const member = finalMembers[i];
+        if (member.memberType !== PolymerClassMemberType.NewLifecycleMethod && member.memberType !== PolymerClassMemberType.ExistingLifecycleMethod) {
+          continue;
+        }
+        const orderDiff = member.lifecycleOrder - newLifecycleMethod.lifecycleOrder;
+        if (orderDiff > 0) {
+          if (orderDiff < closestNextOrderDiff) {
+            closestNextIndex = i;
+            closestNextOrderDiff = orderDiff;
+          }
+        } else if (orderDiff < 0) {
+          if (orderDiff < closestPrevOrderDiff) {
+            closestPrevIndex = i;
+            closestPrevOrderDiff = orderDiff;
+          }
+        }
+      }
+      let insertIndex;
+      if (closestNextIndex !== -1 || closestPrevIndex !== -1) {
+        insertIndex = closestNextOrderDiff < closestPrevOrderDiff ?
+            closestNextIndex : closestPrevIndex + 1;
+      } else {
+        insertIndex = Math.max(
+            finalMembers.findIndex(m => m.memberType === PolymerClassMemberType.Constructor),
+            finalMembers.findIndex(m => m.memberType === PolymerClassMemberType.IsAccessor),
+            finalMembers.findIndex(m => m.memberType === PolymerClassMemberType.PolymerPropertiesAccessor),
+            finalMembers.findIndex(m => m.memberType === PolymerClassMemberType.PolymerObserversAccessor),
+        );
+        if(insertIndex < 0) {
+          insertIndex = finalMembers.length;
+        } else {
+          insertIndex++;//Insert after
+        }
+      }
+      finalMembers.splice(insertIndex, 0, newLifecycleMethod);
+    }
+    //Asserts about finalMembers
+    const nonConstructorMembers = finalMembers.filter(m => m.memberType !== PolymerClassMemberType.Constructor);
+
+    if(nonConstructorMembers.length !== this.members.length) {
+      throw new Error(`Internal error! Some methods are missed`);
+    }
+    let classDeclaration = ts.createClassDeclaration(undefined, undefined, this.className, undefined, heritageClauses, finalMembers.map(m => m.member))
+    const generatedComments: string[] = [];
+    if(this.classJsDocComments.length > 0) {
+      const commentContent = '*\n' + this.classJsDocComments.map(line => `* ${line}`).join('\n') + '\n';
+      classDeclaration = ts.addSyntheticLeadingComment(classDeclaration, ts.SyntaxKind.MultiLineCommentTrivia, commentContent, true);
+      generatedComments.push(`/*${commentContent}*/`);
+    }
+    return {
+      classDeclaration,
+      generatedComments,
+    };
+
+  }
+
+  private createConstructor(): PolymerClassConstructor | null {
+    if(this.constructorStatements.length === 0) {
+      return null;
+    }
+    let superCall: ts.CallExpression = ts.createCall(ts.createSuper(), [], []);
+    const superCallExpression = ts.createExpressionStatement(superCall);
+    const statements = [superCallExpression, ...this.constructorStatements];
+    const constructorDeclaration = ts.createConstructor([], [], [], ts.createBlock(statements, true));
+
+    return {
+      memberType: PolymerClassMemberType.Constructor,
+      member: constructorDeclaration,
+      originalPos: -1
+    };
+  }
+
+  public addClassJSDocComments(lines: string[]) {
+    this.classJsDocComments.push(...lines);
+  }
+}
\ No newline at end of file
diff --git a/tools/polygerrit-updater/src/utils/unexpectedValue.ts b/tools/polygerrit-updater/src/utils/unexpectedValue.ts
new file mode 100644
index 0000000..690c283
--- /dev/null
+++ b/tools/polygerrit-updater/src/utils/unexpectedValue.ts
@@ -0,0 +1,17 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+export function unexpectedValue<T>(x: T): never {
+  throw new Error(`Unexpected value '${x}'`);
+}
diff --git a/tools/polygerrit-updater/tsconfig.json b/tools/polygerrit-updater/tsconfig.json
new file mode 100644
index 0000000..37ff1b2
--- /dev/null
+++ b/tools/polygerrit-updater/tsconfig.json
@@ -0,0 +1,67 @@
+{
+  "compilerOptions": {
+    /* Basic Options */
+    // "incremental": true,                   /* Enable incremental compilation */
+    "target": "es2015",                          /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
+    "module": "commonjs",                     /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
+    // "lib": [],                             /* Specify library files to be included in the compilation. */
+    // "allowJs": true,                       /* Allow javascript files to be compiled. */
+    // "checkJs": true,                       /* Report errors in .js files. */
+    // "jsx": "preserve",                     /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
+    // "declaration": true,                   /* Generates corresponding '.d.ts' file. */
+    // "declarationMap": true,                /* Generates a sourcemap for each corresponding '.d.ts' file. */
+    "sourceMap": true,                     /* Generates corresponding '.map' file. */
+    // "outFile": "./",                       /* Concatenate and emit output to single file. */
+    "outDir": "./js",                        /* Redirect output structure to the directory. */
+    "rootDir": ".",                       /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
+    // "composite": true,                     /* Enable project compilation */
+    // "tsBuildInfoFile": "./",               /* Specify file to store incremental compilation information */
+    // "removeComments": true,                /* Do not emit comments to output. */
+    // "noEmit": true,                        /* Do not emit outputs. */
+    // "importHelpers": true,                 /* Import emit helpers from 'tslib'. */
+    // "downlevelIteration": true,            /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
+    // "isolatedModules": true,               /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
+
+    /* Strict Type-Checking Options */
+    "strict": true,                           /* Enable all strict type-checking options. */
+    "noImplicitAny": true,                 /* Raise error on expressions and declarations with an implied 'any' type. */
+    // "strictNullChecks": true,              /* Enable strict null checks. */
+    // "strictFunctionTypes": true,           /* Enable strict checking of function types. */
+    // "strictBindCallApply": true,           /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
+    // "strictPropertyInitialization": true,  /* Enable strict checking of property initialization in classes. */
+    // "noImplicitThis": true,                /* Raise error on 'this' expressions with an implied 'any' type. */
+    // "alwaysStrict": true,                  /* Parse in strict mode and emit "use strict" for each source file. */
+
+    /* Additional Checks */
+    // "noUnusedLocals": true,                /* Report errors on unused locals. */
+    // "noUnusedParameters": true,            /* Report errors on unused parameters. */
+    // "noImplicitReturns": true,             /* Report error when not all code paths in function return a value. */
+    // "noFallthroughCasesInSwitch": true,    /* Report errors for fallthrough cases in switch statement. */
+
+    /* Module Resolution Options */
+    "moduleResolution": "node",            /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
+    "baseUrl": "./",                       /* Base directory to resolve non-absolute module names. */
+    "paths": {
+      "*": [ "node_modules/*" ]
+    },                           /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
+    // "rootDirs": [],                        /* List of root folders whose combined content represents the structure of the project at runtime. */
+    // "typeRoots": [],                       /* List of folders to include type definitions from. */
+    // "types": [],                           /* Type declaration files to be included in compilation. */
+    "allowSyntheticDefaultImports": true,  /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
+    "esModuleInterop": true                   /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
+    // "preserveSymlinks": true,              /* Do not resolve the real path of symlinks. */
+    // "allowUmdGlobalAccess": true,          /* Allow accessing UMD globals from modules. */
+
+    /* Source Map Options */
+    // "sourceRoot": "",                      /* Specify the location where debugger should locate TypeScript files instead of source locations. */
+    // "mapRoot": "",                         /* Specify the location where debugger should locate map files instead of generated locations. */
+    // "inlineSourceMap": true,               /* Emit a single file with source maps instead of having a separate file. */
+    // "inlineSources": true,                 /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
+
+    /* Experimental Options */
+    // "experimentalDecorators": true,        /* Enables experimental support for ES7 decorators. */
+    // "emitDecoratorMetadata": true,         /* Enables experimental support for emitting type metadata for decorators. */
+
+  },
+  "include": ["./src/**/*"]
+}
diff --git a/version.bzl b/version.bzl
index f3c5399..fb1e5ca 100644
--- a/version.bzl
+++ b/version.bzl
@@ -2,4 +2,4 @@
 # Used by :api_install and :api_deploy targets
 # when talking to the destination repository.
 #
-GERRIT_VERSION = "3.1.1-SNAPSHOT"
+GERRIT_VERSION = "3.2.0-SNAPSHOT"