Merge branch 'stable-2.16' into stable-3.0

* 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: Ifc4d373e8094420f34f589a930e98d62bcd9e6c8