AVRCP: Add PlaybackState for Track Changed

MediaController.getMetadata() updates out of sync with
MediaController.getPlaybackState(), causing issues because we use
PlaybackState.getCurrentQueueId() to sent track IDs to AVRCP CT.

Add getCurrentQueueId() as an indicator of track changes.

Remove counting how many tracks have played since it's inaccurate.

Test: connect to carkit, skip tracks, metadata is updating correctly
Bug: 37707672
Change-Id: I5d190933b847622ec858eab38828902cf798f8e1