Merge "mediaserver: add more hwbinder threads" into rvc-dev am: 2038329cf5 am: 90dcc0b7d3

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/12046706

Change-Id: Ib4806d6bc685151ce1545f762b81fb40f286c8f5