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

content/renderer/media/media_stream_center.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 CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CENTER_H_
 #define CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CENTER_H_
 
 #include <map>
 
 #include "base/basictypes.h"
@@ skipping 12 matching lines @@
 }
 
 namespace content {
 class PeerConnectionDependencyFactory;
 
 class CONTENT_EXPORT MediaStreamCenter
     : NON_EXPORTED_BASE(public blink::WebMediaStreamCenter) {
  public:
   MediaStreamCenter(blink::WebMediaStreamCenterClient* client,
                     PeerConnectionDependencyFactory* factory);
-  virtual ~MediaStreamCenter();
+  ~MediaStreamCenter() override;
 
  private:
-  virtual void didCreateMediaStreamTrack(
+  void didCreateMediaStreamTrack(
       const blink::WebMediaStreamTrack& track) override;
 
-  virtual void didEnableMediaStreamTrack(
+  void didEnableMediaStreamTrack(
       const blink::WebMediaStreamTrack& track) override;
 
-  virtual void didDisableMediaStreamTrack(
+  void didDisableMediaStreamTrack(
       const blink::WebMediaStreamTrack& track) override;
 
-  virtual void didStopLocalMediaStream(
-      const blink::WebMediaStream& stream) override;
+  void didStopLocalMediaStream(const blink::WebMediaStream& stream) override;
 
-  virtual bool didStopMediaStreamTrack(
+  bool didStopMediaStreamTrack(
       const blink::WebMediaStreamTrack& track) override;
 
-  virtual blink::WebAudioSourceProvider*
-      createWebAudioSourceFromMediaStreamTrack(
-          const blink::WebMediaStreamTrack& track) override;
+  blink::WebAudioSourceProvider* createWebAudioSourceFromMediaStreamTrack(
+      const blink::WebMediaStreamTrack& track) override;
 
+  void didCreateMediaStream(blink::WebMediaStream& stream) override;
 
-  virtual void didCreateMediaStream(
-      blink::WebMediaStream& stream) override;
+  bool didAddMediaStreamTrack(const blink::WebMediaStream& stream,
+                              const blink::WebMediaStreamTrack& track) override;
 
-  virtual bool didAddMediaStreamTrack(
+  bool didRemoveMediaStreamTrack(
       const blink::WebMediaStream& stream,
       const blink::WebMediaStreamTrack& track) override;
 
-  virtual bool didRemoveMediaStreamTrack(
-      const blink::WebMediaStream& stream,
-      const blink::WebMediaStreamTrack& track) override;
-
   // |rtc_factory_| is a weak pointer and is owned by the RenderThreadImpl.
   // It is valid as long as  RenderThreadImpl exist.
   PeerConnectionDependencyFactory* rtc_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaStreamCenter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_MEDIA_STREAM_CENTER_H_