am 9c99c55d: (-s ours) am 9395dab7: (-s ours) am ff3362f0: (-s ours) Merge "DO NOT MERGE - [ActivityManager] Ensure consistency behavior when a background activity brings another existed activity to front."

* commit '9c99c55d03a66ad5ba47584340c527c0f843bbe8':
  DO NOT MERGE - [ActivityManager] Ensure consistency behavior when a background activity brings another existed activity to front.