Merge "[Output Switcher] Use Thread-safe list to store mediaDevices in...

Merge "[Output Switcher] Use Thread-safe list to store mediaDevices in MediaManager" into tm-dev am: 82c3268c am: 84612594 am: 65a3d8eb am: 2b2abc76

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/18911999



Change-Id: Ic1507aa392fb30da8d3cf4f564b683eff5b45339
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>