Merge branch 'stable-2.15' into stable-2.16 * stable-2.15: Upgrade bazlets to latest stable-2.15 to build with 2.15.19 API Upgrade bazlets to latest stable-2.14 to build with 2.14.21 API Change-Id: I236f394e2898f979c11a30d0b9b7f0f552efd395