Update 2.15.8 release notes

Change-Id: I22ce1cdfd75c1a60e0a32f57e7021fdc14702b8a
diff --git a/pages/site/releases/2.15.md b/pages/site/releases/2.15.md
index 403cc08..dc91c9c 100644
--- a/pages/site/releases/2.15.md
+++ b/pages/site/releases/2.15.md
@@ -399,6 +399,16 @@
 
 ### 2.15.8
 
+* [Issue 10082](https://bugs.chromium.org/p/gerrit/issues/detail?id=10082):
+Decouple online reindex activation from index module.
+
+  Plugins were not loaded before online indexing was triggered, resulting
+  in plugin-contributed submit rules not being evaluated during indexing.
+
+  Online reindex activation is now decoupled from the index module and
+  thus postpones the triggering of online reindexing until after loading
+  of the plugins.
+
 * [Issue 9024](https://bugs.chromium.org/p/gerrit/issues/detail?id=9024):
 Fix setting `PRIVATE` and `WIP` for updated changes in console report.
 
@@ -423,7 +433,12 @@
 * [Issue 10106](https://bugs.chromium.org/p/gerrit/issues/detail?id=10106):
 Fix incorrect json in the example for the 'Set Access' REST endpoint.
 
-* Upgrade elasticsearch-rest-client to 6.5.3.
+* [Issue 10263](https://bugs.chromium.org/p/gerrit/issues/detail?id=10263):
+Include edit ref in `EditInfo` element returned by the edit API.
+
+  It was not possible for users of the Java API to get the edit ref.
+
+* Upgrade elasticsearch-rest-client to 6.5.4.
 
 * Discontinue support for Elasticsearch 2.4.
 
@@ -440,8 +455,15 @@
 
 * Upgrade jackson-core to 2.9.8.
 
+  [Version 2.9.8](https://github.com/FasterXML/jackson/wiki/Jackson-Release-2.9.8)
+  includes several bug fixes, including security fixes.
+
 * Add a new method on the account API to set the account name.
 
+* Add new methods on the project API to get/set the project's `HEAD`.
+
+* Add a new method on the commit API to get "included in" information.
+
 ### 2.15.7
 
 * [Issue 9952](https://bugs.chromium.org/p/gerrit/issues/detail?id=9952):