Merge branch 'stable-2.12'

* stable-2.12:
  Build with API version 2.12

Change-Id: Ia60b0ed07728edc6bb99974e5c4cd9bb0f9ed844
tree: 5f31cf891af86f03a8e93d2d5a0469c02bec859c
  1. .buckconfig
  2. .gitignore
  3. BUCK
  4. lib/
  5. src/