DO NOT MERGE: Fix deadlock in AcitivityManagerService. am: 2d608378f4  -s ours am: bab9c1006a am: e85152c2fc am: ac143d2dfd  -s ours am: 20bafe850d am: 923f622c15 am: 042fb63071
am: 3c7e989835  -s ours

Change-Id: Ieb72c957f1d58cea635bcd7b9449b19b3341efc8