DO NOT MERGE - improve audio effect framwework thread safety am: b47a5ab107 am: 26cf2f4d73 am: 73a152960b  -s ours am: 21d6eafd26  -s ours am: 6c5deab4f2 am: 9685820100  -s ours
am: 6608eddab9

Change-Id: I90c4642628db7be0f6756885bb56b09b780bdbe3