Merge changes Ib5cc22db,I93e0c449,I65cd4cfd,I1cef3bd4,I628c0468

* changes:
  MIDI Manager: Add explicit close mechanism for input and output ports
  MidiDeviceService: Add getDeviceInfo() accessor method
  Add MidiDevice.close() method so we can clean up our ServiceConnection
  Make MidiSender and MidiReceiver abstract classes, rename MidiReceiver.post() to receive()
  Eliminate MidiPort base class for MidiInputPort and MidiOutputPort