Merge branch 'stable-3.1'

* stable-3.1:
  Upgrade bazlets to latest stable-3.0 to build with 3.0.7 API
  Upgrade bazlets to latest stable-2.16 to build with 2.16.16 API

Change-Id: If08cefab0c60dab5d8ee2085088f69033a6a97dc