BassClient: Verify connection state change intents

This is needed to support unit tests on the BassClientState machine.

Bug: 239546757
Tag: #feature
Sponsor: jpawlowski@
Test: atest BluetoothInstrumentationTests
Change-Id: Ic2909d053e21e8c5d83e63758182335ad684e1a1
Merged-In: Ic2909d053e21e8c5d83e63758182335ad684e1a1
(cherry picked from commit ce1d5ffebb1ac4482b6ab78d8354f00a24239717)