Update TestVideoRenderer with video decoding capabilities

remoting/test/test_video_renderer.h

 // Copyright 2015 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_TEST_TEST_VIDEO_RENDERER_H_
 #define REMOTING_TEST_TEST_VIDEO_RENDERER_H_
 
-#include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/threading/thread_checker.h"
+#include "media/base/video_frame.h"
 #include "remoting/client/video_renderer.h"
+#include "remoting/protocol/session_config.h"
 #include "remoting/protocol/video_stub.h"
 
+namespace base {
+class Thread;
+class SingleThreadTaskRunner;
+}
+
+namespace webrtc {
+class DesktopFrame;
+}
+
 namespace remoting {
 namespace test {
 
 // Processes video packets as they are received from the remote host.

[joedow, 2015/06/30 20:07:12]

Can you add a comment here about how threads and TaskRunners are managed by this
class.

Basically it is important to say that this must be created on a thread with an
existing MessageLoop and that this calss will use that message loop to execute
the done callbacks passed by the caller of ProcessVideoPacket. 
remote_host_info_fetcher.h has an example of the type of info that should be
included.

 class TestVideoRenderer : public VideoRenderer, public protocol::VideoStub {
  public:
   TestVideoRenderer();
   ~TestVideoRenderer() override;
 
   // VideoRenderer interface.
   void OnSessionConfig(const protocol::SessionConfig& config) override;
   ChromotingStats* GetStats() override;
   protocol::VideoStub* GetVideoStub() override;
 
- private:
   // protocol::VideoStub interface.
   void ProcessVideoPacket(scoped_ptr<VideoPacket> video_packet,
                           const base::Closure& done) override;
 
-  // Track the number of populated video frames which have been received.
-  int video_frames_processed_;
+  // Initialize a decoder to decode video packets.
+  void SetDecoderForDecoding(const protocol::ChannelConfig::Codec codec);

[joedow, 2015/06/30 20:07:12]

SetCodecForDecoding (or just SetCodec)

[liaoyuke, 2015/06/30 21:15:01]

Done.

+
+  // Returns a copy of the current buffer.
+  scoped_ptr<webrtc::DesktopFrame> GetBufferForTest() const;
+
+ private:
+  // The actual implementation resides in Core class.
+  class Core;
+  scoped_ptr<Core> core_;
+
+  // Used to ensure TestVideoRenderer methods are called on the same thread.
+  base::ThreadChecker thread_checker_;
+
+  // Used to decode and process video packets.
+  scoped_ptr<base::Thread>  video_decode_thread_;
+
+  // Used to post tasks to video decode thread.
+  scoped_refptr<base::SingleThreadTaskRunner> video_decode_task_runner_;
+
+  // Used to weakly bind |this| to methods.
+  // NOTE: Weak pointers must be invalidated before all other member variables.
+  base::WeakPtrFactory<TestVideoRenderer> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TestVideoRenderer);
 };
 
 }  // namespace test
 }  // namespace remoting
 
 #endif  // REMOTING_TEST_TEST_VIDEO_RENDERER_H_