Extract private and WIP state information from change

This can be used to further control which comments are actually
posted, and how.

Change-Id: I370ab34d6151735aa99ecb17ccf9d4e6c473a22d

src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyAttributeExtractor.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyAttributeExtractor.java b/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyAttributeExtractor.java
index 6770a3c..0038e22 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyAttributeExtractor.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyAttributeExtractor.java
@@ -57,6 +57,8 @@
         .put("changeUrl", changeAttribute.url)
         .put("formatChangeUrl", its.createLinkForWebui(changeAttribute.url, changeAttribute.url))
         .put("status", changeAttribute.status != null ? changeAttribute.status.toString() : "")
+        .put("private", changeAttribute.isPrivate != null ? changeAttribute.isPrivate.toString() : "false")
+        .put("wip", changeAttribute.wip != null ? changeAttribute.wip.toString() : "false")
         .putAll(extractFrom(changeAttribute.owner, "owner"))
         .build();
   }

src/main/resources/Documentation/config-rulebase-common.md

diff --git a/src/main/resources/Documentation/config-rulebase-common.md b/src/main/resources/Documentation/config-rulebase-common.md
index 5e57925..4d970b6 100644
--- a/src/main/resources/Documentation/config-rulebase-common.md
+++ b/src/main/resources/Documentation/config-rulebase-common.md
@@ -483,6 +483,12 @@
 `topic`
 : name of the topic the change belongs to.
 
+`private`
+:   whether the change is marked private
+
+`wip`
+:   whether the change is marked work in progress (WIP)
+
 ### Common properties for events on a patch set
 
 `authorEmail`