Merge "Add BluetoothDevice#connect and BluetoothDevice#disconnect as System APIs" into stage-aosp-master am: 4a39b54ec1 am: 0db21e73d3 am: 269e7b39db

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/15936310

Change-Id: Ia70cd735636ac8311878d30e181aa3d1bca9a289