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

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



Change-Id: I10227b5f9f48e1dc1f303410aaaa56705890cf3d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>