Merge "Expose service changed event to application (3/3)" am: e8e83ee0 am:...

Merge "Expose service changed event to application (3/3)" am: e8e83ee0 am: 49f2c14f am: d8a7fd57 am: dd4a570d

Original change: https://android-review.googlesource.com/c/platform/packages/apps/Bluetooth/+/1433964

Change-Id: Ie537295da3baed7459d9fa9968ff0787dba1527f