Refactor A2dpSink and AvrcpController

Update Java side code to support command and response to addressed
device.  Simplify connection logic to create a new state machine per
addressed device rather than allowing connections to transfer from one
device to another, this eliminates the possibility of having AVCRP
connected to one device and A2dp connected to another one.

Bug: 120673113
Test: runtest bluetooth
Change-Id: Ia4feba10ea8ebc22834def42b57b7abf923bee04