Merge "Fix volume slider not showing when casting in the background" into udc-dev am: f96e49ed

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23726250



Change-Id: If4f9648aa05bfcff541023bea3ac160a279aeb86
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>