Generate CONNECTION_STATE_CHANGED intent when A2dpService is stopped

Generate the intent as if connections were disconnected
locally or remotely.

Bug: 360034472
Bug: 277573958
Bug: 277846618
Test: atest BluetoothInstrumentationTests
Flag: com.android.bluetooth.a2dp_broadcast_connection_state_when_turned_off
Change-Id: I40b09e72e879fc702fb06028fa765c0db6af663a