Merge branch 'stable-2.16' into stable-3.0

* stable-2.16:
  Update Gerrit API to 2.16.11.1
  Update Gerrit API to 2.15.16
  Update Gerrit API to 2.15.15

Change-Id: Ic2273dbc6ba69126e12b8a1671dc3ff6060b125b