RemoteController: extract interface conflicting with CTS test (1/2)

android.media.cts.RemoteControllerTest#testOnClientUpdateListenerUnchanged
will fail because it expects no extra methods to be added to the
listeners and the current AVRCP impl simply appended methods to that
listener. In 13 this was fixed by creating a separate listener for those
callbacks. Backport that listener to fix the test.

Ticket: HAM-1300, CYNGNOS-2716

Change-Id: I05bdac4fcc581c09e03fe7feb216d012a4c5e62b
Signed-off-by: Roman Birg <roman@cyngn.com>