Move android mediaplayer from render process to browser process.

content/browser/android/media_player_manager_android.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_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_ANDROID_H_
+#define CONTENT_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_ANDROID_H_
+
+#include <map>
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "base/time.h"
+#include "content/public/browser/render_view_host_observer.h"
+#include "media/base/android/media_player_bridge.h"
+#include "media/base/android/media_player_bridge_manager.h"
+
+namespace content {
+
+// This class manages all the android mediaplayer objects. It receives the

[scherkus (not reviewing), 2012/09/07 13:17:35]

nit: replace "mediaplayer" with "media player"

even better if there is a concrete class name you can refer to -- i.e.,
"MediaPlayerBridge objects"

[qinmin, 2012/09/07 22:48:27]

Done.

+// control operations from the the renderer process, and forward

[scherkus (not reviewing), 2012/09/07 13:17:35]

s/the control/control/

[scherkus (not reviewing), 2012/09/07 13:17:35]

s/, and forward/ and forwards/

[qinmin, 2012/09/07 22:48:27]

Done.

[qinmin, 2012/09/07 22:48:27]

Done.

+// them to corresponding mediaplayers. Media notification messages are sent
+// this class first, before it forwards them to the renderer process.

[scherkus (not reviewing), 2012/09/07 13:17:35]

Are media notification messages callbacks from MediaPlayerBridge objects?

If so, perhaps reword. "sent" is usually used in the context of IPC messages so
this reads a little funny.

[qinmin, 2012/09/07 22:48:27]

Yes, they are callbacks from MPB. Rephrased the sentence here. 
On 2012/09/07 13:17:35, scherkus wrote:

+class MediaPlayerManagerAndroid : public content::RenderViewHostObserver,

[scherkus (not reviewing), 2012/09/07 13:17:35]

use initializer list style

class A
    : public B,
      public C {
};

[qinmin, 2012/09/07 22:48:27]

Done.

+                                  public media::MediaPlayerBridgeManager {
+ public:
+  explicit MediaPlayerManagerAndroid(RenderViewHost* render_view_host);
+  virtual ~MediaPlayerManagerAndroid();
+
+  // RenderViewHostObserver overrides.
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  // An internal method that checks for current time routinely and generates
+  // time update events.
+  void OnTimeUpdate(int player_id, base::TimeDelta current_time);
+
+  // Callbacks needed by media::MediaPlayerBridge.
+  void OnPrepared(int player_id, base::TimeDelta duration);
+  void OnPlaybackComplete(int player_id);
+  void OnBufferingUpdate(int player_id, int percentage);
+  void OnSeekComplete(int player_id, base::TimeDelta current_time);
+  void OnError(int player_id, int error);
+  void OnVideoSizeChanged(int player_id, int width, int height);
+
+  // media::MediaPlayerBridgeManager overrides.
+  virtual void RequestMediaResources(media::MediaPlayerBridge* player) OVERRIDE;
+  virtual void ReleaseMediaResources(media::MediaPlayerBridge* player) OVERRIDE;
+
+  // Release all the players managed by this object.
+  void CleanUpAllPlayers();
+
+  media::MediaPlayerBridge* GetPlayer(int player_id);
+
+ private:
+  // Message handlers.
+  void OnInitialize(int player_id, const std::string& url);
+  void OnStart(int player_id);
+  void OnSeek(int player_id, base::TimeDelta time);
+  void OnPause(int player_id);
+  void OnReleaseResources(int player_id);
+  void OnDestroyPlayer(int player_id);
+
+  // An array of managed players.
+  ScopedVector<media::MediaPlayerBridge> players_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaPlayerManagerAndroid);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_ANDROID_MEDIA_PLAYER_MANAGER_ANDROID_H_