WIP - WebMediaPlayer switch media renderer.

media/remoting/remoting_controller.h

Index: media/remoting/remoting_controller.h
diff --git a/media/remoting/remoting_controller.h b/media/remoting/remoting_controller.h
new file mode 100644
index 0000000000000000000000000000000000000000..6e9b776af20ee7c8a5be1153f86c1e16449c52f3
--- /dev/null
+++ b/media/remoting/remoting_controller.h
@@ -0,0 +1,82 @@
+// Copyright 2016 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_REMOTING_REMOTING_CONTROLLER_H_
+#define MEDIA_REMOTING_REMOTING_CONTROLLER_H_
+
+#include "base/callback.h"
+#include "base/memory/weak_ptr.h"
+#include "media/base/mediaplayer_observer.h"
+#include "media/mojo/interfaces/remoting.mojom.h"
+#include "mojo/public/cpp/bindings/binding.h"
+
+// This class does the following:
+// 1) Sends/Receives messages from/to Remoter;
+// 2) Gets info from media::WebMediaPlayerImpl;

[miu, 2016/09/30 08:12:10]

For #2, WMPI is not known in media/remoting code. Suggestion:

  2) Monitors player events as a MediaPlayerObserver.

[xjz, 2016/10/01 00:28:41]

Done.

+// 3) May trigger the switch of the media renderer between local playback
+// and remoting.
+//
+namespace media {
+
+class MEDIA_EXPORT RemotingController final : public MediaPlayerObserver,
+                                              public mojom::RemotingSource {
+ public:
+  explicit RemotingController(mojom::RemoterFactory* remoter_factory);

[miu, 2016/09/30 08:12:10]

This looks like you're injecting a RemoterFactory as a dependency. So, please
comment that |remoter_factory| is just being used to create a Remoter and need
not remain valid after the constructor returns.

[xjz, 2016/10/01 00:28:41]

Done.

+  ~RemotingController() override;
+
+  // RemotingSource implementations.
+  void OnSinkAvailable() override;
+  void OnSinkGone() override;
+  void OnStarted() override;
+  void OnStartFailed(mojom::RemotingStartFailReason reason) override;
+  void OnMessageFromSink(const std::vector<uint8_t>& message) override;
+  void OnStopped(mojom::RemotingStopReason reson) override;
+
+  // MediaPlayerObserver implementation.
+  void OnEnteredFullscreen() override;
+  void OnExitedFullscreen() override;
+  void OnSetCdm(CdmContext* cdm_context) override;
+  void OnDecoderConfigChanged(const AudioDecoderConfig& audio_config,
+                              const VideoDecoderConfig& video_config) override;
+  void SetSwitchRenderCallback(
+      const MediaPlayerObserver::SwitchRendererCallback& cb) override;
+
+  // Tells which renderer should be used.
+  bool is_remoting();

[miu, 2016/09/30 08:12:10]

Simple accessors should be defined inline (and const):

  bool is_remoting() const { return is_remoting_; }

[xjz, 2016/10/01 00:28:41]

Done.

+
+ private:
+  bool isVideoConfigSupported();
+  bool isAudioConfigSupported();
+
+  // Determines whether to enter or leave Remoting mode and switches if
+  // necessary.
+  void Update();
+
+  // Indicates if this media element or its ancestor enters full screen.
+  bool is_fullscreen_;
+
+  // Indicates the remoting sink availablity.
+  bool is_sink_available_;
+
+  // Indicates if remoting is started.
+  bool is_remoting_;
+
+  // Current audio/video config.
+  VideoDecoderConfig video_decoder_config_;
+  AudioDecoderConfig audio_decoder_config_;
+
+  // The callback to switch the media renderer.
+  MediaPlayerObserver::SwitchRendererCallback switch_renderer_cb_;
+
+  mojo::Binding<mojom::RemotingSource> binding_;
+  mojom::RemoterPtr remoter_;
+
+  const scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(RemotingController);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_REMOTING_REMOTING_CONTROLLER_H_