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

* commit 'fe3ecdab1b461d811825ce363d7041f3c8c120c3':
  Revert "Internal API for cross-task Activity used by assistant."

Change-Id: If16a43f4a17e71cc12ed7c912ed5e6a46c85e56c