Refactor content::RenderAudioSourceProvider as webkit_media::WebAudioSourceProviderImpl.

content/renderer/media/render_audiosourceprovider.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.
-//
-// RenderAudioSourceProvider provides a bridge between classes:
-//     WebKit::WebAudioSourceProvider <---> media::AudioRendererSink
-//
-// RenderAudioSourceProvider is a "sink" of audio, and uses a default
-// AudioOutputDevice if a client has not explicitly been set.
-//
-// WebKit optionally sets a client, and then periodically calls provideInput()
-// to render a certain number of audio sample-frames.  provideInput()
-// uses the renderer to get this data, and then massages it into the form
-// required by provideInput().  In this case, the default AudioOutputDevice
-// is no longer used.
-//
-// THREAD SAFETY:
-// It is assumed that the callers to setClient() and provideInput()
-// implement appropriate locking for thread safety when making
-// these calls.  This happens in WebKit.
-
-#ifndef CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_
-#define CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_
-
-#include "base/synchronization/lock.h"
-#include "media/base/audio_renderer_sink.h"
-#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebVector.h"
-#include "third_party/WebKit/Source/WebKit/chromium/public/WebAudioSourceProvider.h"
-
-namespace WebKit {
-class WebAudioSourceProviderClient;
-}
-
-namespace content {
-
-class RenderAudioSourceProvider
-    : public WebKit::WebAudioSourceProvider,
-      public media::AudioRendererSink {
- public:
-  explicit RenderAudioSourceProvider(int source_render_view_id);
-
-  // WebKit::WebAudioSourceProvider implementation.
-
-  // WebKit calls setClient() if it desires to take control of the rendered
-  // audio stream.  We call client's setFormat() when the audio stream format
-  // is known.
-  virtual void setClient(WebKit::WebAudioSourceProviderClient* client);
-
-  // If setClient() has been called, then WebKit calls provideInput()
-  // periodically to get the rendered audio stream.
-  virtual void provideInput(const WebKit::WebVector<float*>& audio_data,
-                            size_t number_of_frames);
-
-  // AudioRendererSink implementation.
-  virtual void Start() OVERRIDE;
-  virtual void Stop() OVERRIDE;
-  virtual void Play() OVERRIDE;
-  virtual void Pause(bool flush) OVERRIDE;
-  virtual bool SetVolume(double volume) OVERRIDE;
-  virtual void Initialize(const media::AudioParameters& params,
-                          RenderCallback* renderer) OVERRIDE;
-
- protected:
-  virtual ~RenderAudioSourceProvider();
-
- private:
-  // Set to true when Initialize() is called.
-  bool is_initialized_;
-  int channels_;
-  int sample_rate_;
-
-  bool is_running_;
-  media::AudioRendererSink::RenderCallback* renderer_;
-  WebKit::WebAudioSourceProviderClient* client_;
-
-  // Protects access to sink_
-  base::Lock sink_lock_;
-
-  // default_sink_ is the default sink.
-  scoped_refptr<media::AudioRendererSink> default_sink_;
-
-  DISALLOW_IMPLICIT_CONSTRUCTORS(RenderAudioSourceProvider);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_RENDERER_MEDIA_RENDER_AUDIOSOURCEPROVIDER_H_