Fix 5044158: Integrate music transport control into LockScreen

This integrates a new version of TransportControlView into LockScreen
and adds plumbing to handle new AudioService events to show/hide the view
and updates the required assets for all devices.

Updated to use new AudioManager API. Since the current API only supports
one RCD, the handler now lives in TransportControlView.

Change-Id: I220d4dd760bef35bd84209adc3c5829bf5bc9a2c