Web MIDI: style clean up

media/midi/midi_manager_alsa.h

 // Copyright 2014 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_ALSA_H_
 #define MEDIA_MIDI_MIDI_MANAGER_ALSA_H_
 
 #include <alsa/asoundlib.h>
 #include <map>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/stl_util.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread.h"
 #include "base/values.h"
 #include "media/midi/midi_manager.h"
 
 namespace media {
 
-class MEDIA_EXPORT MidiManagerAlsa : public MidiManager {
+class MEDIA_EXPORT MidiManagerAlsa final : public MidiManager {
  public:
   MidiManagerAlsa();
   ~MidiManagerAlsa() override;
 
   // MidiManager implementation.
   void StartInitialization() override;
   void DispatchSendMidiData(MidiManagerClient* client,
                             uint32 port_index,
                             const std::vector<uint8>& data,
                             double timestamp) override;
@@ skipping 282 matching lines @@
 
   bool event_thread_shutdown_;  // guarded by shutdown_lock_
   base::Lock shutdown_lock_;    // guards event_thread_shutdown_
 
   DISALLOW_COPY_AND_ASSIGN(MidiManagerAlsa);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MIDI_MIDI_MANAGER_ALSA_H_