Standardize usage of virtual/override/final in remoting/

remoting/codec/audio_decoder_opus.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 REMOTING_CODEC_AUDIO_DECODER_OPUS_H_
 #define REMOTING_CODEC_AUDIO_DECODER_OPUS_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "remoting/codec/audio_decoder.h"
 
 struct OpusDecoder;
 
 namespace remoting {
 
 class AudioPacket;
 
 class AudioDecoderOpus : public AudioDecoder {
  public:
   AudioDecoderOpus();
-  virtual ~AudioDecoderOpus();
+  ~AudioDecoderOpus() override;
 
   // AudioDecoder interface.
-  virtual scoped_ptr<AudioPacket> Decode(
-      scoped_ptr<AudioPacket> packet) override;
+  scoped_ptr<AudioPacket> Decode(scoped_ptr<AudioPacket> packet) override;
 
  private:
   void InitDecoder();
   void DestroyDecoder();
   bool ResetForPacket(AudioPacket* packet);
 
   int sampling_rate_;
   int channels_;
   OpusDecoder* decoder_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioDecoderOpus);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_CODEC_AUDIO_DECODER_OPUS_H_