Fixing crash in BluetoothPbapService.

If Bluetooth is turned off while there is an PBAP connect request
pending, the status bar notification or yes/no activity will not
disappear. If user selects yes, an intent will start PbapService
again. PbapService will try to make the device trusted. As this
instance of PbapService don't have any connected device, crash will
occur.

Make sure status bar notification or yes/no activity disappears, by
sending timeout intent when Bluetooth is turned off.
Also, PbapReceiver should not forward any intents except STATE_ON
if Bluetooth is off as this will start the PbapService.

Change-Id: Iee4f95ab2de34db6e00ff9b1fd7f8677947b8f4f