Merge branch 'stable-2.8'

* stable-2.8:
  Support committing Lucene writes within a fixed interval
  Fix ArrayIndexOutOfBoundsException on intraline diff again

Conflicts:
	gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java

Change-Id: I7b93d81d8e5c53615ef1684b653d6fa9e941d935