Merge branch 'stable-2.15' into stable-2.16

* stable-2.15:
  Format Java files with google-java-format 1.7
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14
  Update bazlets to fix build with bazel 0.23
  Update bazlets to fix build with bazel 0.23

Change-Id: If50fc0baaa36d788657332feb2ecef0c770b8657