Merge "Revert "Removed BluetoothDevice#prepareToEnterProcess"" am: 168b5655a4 am: a3b55d5079 am: 170597987c am: fddbf6e930

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1869964

Change-Id: I162c539a488e0977817a259098ef83694879fcf4