Merge branch 'stable-2.16'

* stable-2.16:
  Upgrade bazlets to latest stable-2.16 to build with 2.16.7 API
  Upgrade bazlets to latest stable-2.15 to build with 2.15.12 API
  Upgrade bazlets to latest stable-2.14 to build with 2.14.19 API

Change-Id: I9bee6614ed0d071ef5ffb9bfe78b5e9e98d5a129