BluetoothAdapter: permission for registerBluetoothConnection

The method require permission directly in U
The unregister method return a wrong value in U

Bug: 348695510
Bug: 347204361
Bug: 339585576
Bug: 341846395
Flag: Exempt TEST_ONLY
Test: atest CtsBluetoothTestCases#BluetoothAdapterTest
Merged-In: I09fe87f3b3e16b37a66d87b6ba2cb0f293b61a17
Change-Id: I91ce0763b3effde37fecd87d0bb6ed1ef2cce399