DO NOT MERGE - improve audio effect framwework thread safety am: 84c392104e  -s ours am: 5d5f9cd28a am: 10f61954ba  -s ours am: bb4c9408ec am: 642e5857fe am: b763905a4f am: eef8dc0294  -s ours am: 7454e9d217 am: 5acee4ff97 am: e5de51e57c am: 2c543a3106
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Change-Id: Ib10fc4731e01073b656314f6f549f1642e9ba6c0