Merge changes from topic "c2allocatorbuf" am: 1e05a85fcf am: e00275b92d am: 86570edfaa

Original change: https://android-review.googlesource.com/c/platform/frameworks/av/+/1420188

Change-Id: I5bb8928a9850a7f4f075cfc20c900df9b9608c8b