am d1c9d6e8: am 3b8381e1: am 7bb37c87: am 0480d5d8: Merge "docs: Android SDK 21.1.0 Release Notes" into jb-mr1-dev

# Via Android Git Automerger (3) and others
* commit 'd1c9d6e84969ee36f8a3b74515bae715727866a1':
  docs: Android SDK 21.1.0 Release Notes