Add launch notification for MTP devices.

The CL adds launch notification that are shown after MTP/PTP device is
connected to Android device. By tapping the notification, Users can
launch an applicaiton that can handle USB_DEVICE_ATTACHED intent of MTP
device.

BUG=26611224

Change-Id: I6fd179ccd436531dfff6ff9a50dc2b754c20f190