Update {virtual,override} to follow C++11 style in media.

media/audio/agc_audio_stream.h

 // Copyright (c) 2012 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_AUDIO_AGC_AUDIO_STREAM_H_
 #define MEDIA_AUDIO_AGC_AUDIO_STREAM_H_
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/synchronization/lock.h"
@@ skipping 120 matching lines @@
     base::AutoLock lock(lock_);
     *normalized_volume = normalized_volume_;
   }
 
  private:
   // Sets the automatic gain control (AGC) to on or off. When AGC is enabled,
   // the microphone volume is queried periodically and the volume level can
   // be read in each AudioInputCallback::OnData() callback and fed to the
   // render-side AGC. User must call StartAgc() as well to start measuring
   // the microphone level.
-  virtual bool SetAutomaticGainControl(bool enabled) override {
+  bool SetAutomaticGainControl(bool enabled) override {
     DVLOG(1) << "SetAutomaticGainControl(enabled=" << enabled << ")";
     DCHECK(thread_checker_.CalledOnValidThread());
     agc_is_enabled_ = enabled;
     return true;
   }
 
   // Gets the current automatic gain control state.
-  virtual bool GetAutomaticGainControl() override {
+  bool GetAutomaticGainControl() override {
     DCHECK(thread_checker_.CalledOnValidThread());
     return agc_is_enabled_;
   }
 
   // Takes a new microphone volume sample and stores it in |normalized_volume_|.
   // Range is normalized to [0.0,1.0] or [0.0, 1.5] on Linux.
   // This method is called periodically when AGC is enabled and always on the
   // audio manager thread. We use it to read the current microphone level and
   // to store it so it can be read by the main capture thread. By using this
   // approach, we can avoid accessing audio hardware from a real-time audio
@@ skipping 36 matching lines @@
 
   // Protects |normalized_volume_| .
   base::Lock lock_;
 
   DISALLOW_COPY_AND_ASSIGN(AgcAudioStream<AudioInterface>);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AGC_AUDIO_STREAM_H_