Merge changes from topic \'choreo_ndk\'
am: d66a831

* commit 'd66a831ffc059a80e6cc7c1dc996159eb2f97eba':
  Add choreographer API to the NDK
  Copy over libandroid symbols from platform 21.

Change-Id: I0bf882917fd975d394655becf2220334a6f1a8e5