Merge "AudioPolicyService: Acquire mutex for SoundTriggerSession" into lmp-dev am: 35a587cdc5 am: 27c4e661d4  -s ours am: ac43fbe5a6  -s ours am: f513923b38  -s ours am: a421c87781  -s ours
am: 310807ff52  -s ours

Change-Id: I4ccdd7901825f76976b5a2ba32926452c7d045d2