Web MIDI: introduce MidiService class

media/midi/midi_manager.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_MIDI_MIDI_MANAGER_H_
 #define MEDIA_MIDI_MIDI_MANAGER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 10 matching lines @@
 
 namespace base {
 class SingleThreadTaskRunner;
 }  // namespace base
 
 namespace midi {
 
 // A MidiManagerClient registers with the MidiManager to receive MIDI data.
 // See MidiManager::RequestAccess() and MidiManager::ReleaseAccess()
 // for details.
+// TODO(toyoshim): Consider to have a MidiServiceClient interface.
 class MIDI_EXPORT MidiManagerClient {
  public:
   virtual ~MidiManagerClient() {}
 
   // AddInputPort() and AddOutputPort() are called before CompleteStartSession()
   // is called to notify existing MIDI ports, and also called after that to
   // notify new MIDI ports are added.
   virtual void AddInputPort(const MidiPortInfo& info) = 0;
   virtual void AddOutputPort(const MidiPortInfo& info) = 0;
 
@@ skipping 173 matching lines @@
   // |session_thread_runner_|, |initialization_state_|, |finalize_|, |result_|,
   // |input_ports_| and |output_ports_|.
   base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(MidiManager);
 };
 
 }  // namespace midi
 
 #endif  // MEDIA_MIDI_MIDI_MANAGER_H_