Merge "Revert "Internal API for cross-task Activity used by assistant."" into nyc-mr1-dev am: fe3ecdab1b
am: abb7488998

* commit 'abb74889982603f6070100033c8fa2b1eef3d8de':
  Revert "Internal API for cross-task Activity used by assistant."

Change-Id: Id397afe9221e2562e096befc1b105233618ca7ef