Merge branch 'stable-2.15' into stable-2.16

* stable-2.15:
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14

Change-Id: I661a491eef35c0066a97096dfa58e779b2865c18