DO NOT MERGE: Fix deadlock in AcitivityManagerService. am: b59e73613b am: 2f44f906a6 am: f4844b3416 am: 6f170618ff  -s ours
am: 7f99a18e0e

Change-Id: Ic6e91076e979291bfcbc87bc2e8d71ddd4c700de