Merge "Fix API review comments, add remove callback." into nyc-dev am: d19191d am: 1b65983
am: bd7a5a1

* commit 'bd7a5a1041ea9e8a4075692cac020fd6374b5bb1':
  Fix API review comments, add remove callback.

Change-Id: I55e8eb1f6ae9308abf90d30bac434fc81ed18c7a