Merge "Merge "Introduce a BluetoothConnectionCallback that will fire off...

Merge "Merge "Introduce a BluetoothConnectionCallback that will fire off events when a device is connected or disconnected." am: abe93957 am: 4d0e0a264b am: 07035cb2" into rvc-qpr-dev-plus-aosp am: 9ee26c4355

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1478819

Change-Id: Ic5579ebc90f8a23b799c96704756938ca667a23e