TWS-A2DP: Notify audio service with dummy device address

Refactore notifying active device to audio service for TWS+
device to avoid audio gap when active device is disconnected.
Notify audio service with dummy device address for first connect
and last disconnect of TWS+ earbud.

CRs-fixed: 2246828
Change-Id: I41d215c69b943808e05203e9f6fdf70a046d6210
1 file changed