GATT: Ignore NULL intent to start GATT Service during user switch.

This fix checks if reveived intent in onStartCommand is valid and
not null. During user switch, its observed that sometimes NULL
intent is received when Bluetooth process was restarted from activity
manager for broadcast of BluetoothFtpReceiver.

Change-Id: I472463f3d9b3f9297bb76acaa19add50e35daa95
CRs-Fixed: 2388732
1 file changed