DO NOT MERGE: Fix deadlock in AcitivityManagerService. am: dce4be63bb am: a437e7f3f1 am: c1b2e6db98  -s ours am: ff9a8d74c7  -s ours
am: 51bcb058ad

Change-Id: If639ceb911ea7cfc977bf053f1e897bd7939564f