DO NOT MERGE: Fix deadlock in AcitivityManagerService. am: e8340a9ed5 am: 5c53e1b8bb am: 271aa24036  -s ours am: e44f8fcca4
am: 6b77a4ee55

Change-Id: I04fdab0c6677eb8c5d6ec50ab82a4e1f9da2180f