Merge branch 'stable-2.16'

* stable-2.16:
  Upgrade bazlets to latest stable-2.16 to build with 2.16.8 API
  Upgrade bazlets to latest stable-2.15 to build with 2.15.13 API
  Upgrade bazlets to latest stable-2.14 to build with 2.14.20 API

Change-Id: I6f0e65ea3c459ad334f7548f4eed0e91a3928db4