Merge branch 'stable-2.15' into stable-2.16

* stable-2.15:
  Format Java files with google-java-format 1.7
  Upgrade mockito-core to 2.25.0
  Upgrade bazlets to latest stable-2.15
  Upgrade bazlets to latest stable-2.14
  Update bazlets to fix build with bazel 0.23

Change-Id: I5b3f333d3b73334d33c2d3e09a9911561e8ea763