This should only be landed as part of our upgrade process. This change
will not upgrade Gerrit properly on its own.
Note, we keep Gerrit 3.5 image builds and 3.5 -> 3.6 upgrade jobs in
place until we are certain we won't roll back. Once we've crossed that
threshold we can drop 3.5 image builds, add 3.7 image builds, and update
the upgrade testing to perform a 3.6 -> 3.7 upgrade.
Change-Id: I40c4f96cc40edc5caeb32a1af80069ef784967fd
79e4232914