This release includes a fix [1] that gives a significant performance
improvement in the case when Gerrit loads all external-ids from NoteDb.
This happens whenever the external_ids_map cache gets invalidated or
expires.
With NoteDb containing about 70K external-ids the following times were
measured [2] for loading all external-ids:
* Using JGit without [1]: 10 seconds
* Using JGit with [1]: 2 seconds
[1] https://git.eclipse.org/r/150254
[2] https://gerrit-review.googlesource.com/c/gerrit/+/240194
Change-Id: I32f408f5caead1c9e79d5ef61c2d2888deda05e0