Merge "libaudiohal: implement supportsBluetoothVariableLatency for HIDL" into udc-d1-dev am: e6d09667c9 am: c8ad11d6c0 am: e9fe599b39

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/av/+/23883971

Change-Id: I9e6fdf980962df5685efdacf670933c0f4426687
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>