DO NOT MERGE - improve audio effect framwework thread safety am: bc7f347ff5 am: 068881e79c am: 35912764e9 am: d9e0deef93  -s ours am: 7bb8e04c67
am: 851361eda0

Change-Id: Ie02e050387e13ccf1e20b675949a69299cd8b7ed