Add incoming pairing dialog
Add DisplayPasskey handling of pairing keyboards with 2.1 devices.
Modify code path to show errors when bonding request fails.
Misc fixes like string changes.
Split BluetoothDevice into BluetoothDevice and BluetoothAdapter.
BluetoothAdapter: Represents the local BT adapter. Operations on the local
adapter (start a scan, etc).
BluetoothDevice: Represents a remote BT device. Operations on remote devices
(pair, connect, etc).
- Changed the Passkey confirmation to show Pair/Don't Pair.
- Fixed the problem where the Ok button was showing up as Pair for the error dialog box.
- Disable the toasts when pairing failed in this case. Will need to check if this causes regression in other cases.
