Reland of Split IncomingVideoStream into two implementations, with smoothing and without.

webrtc/common_video/include/incoming_video_stream.h

Index: webrtc/common_video/include/incoming_video_stream.h
diff --git a/webrtc/common_video/include/incoming_video_stream.h b/webrtc/common_video/include/incoming_video_stream.h
index f96a23dbeabaff21de247594d11f0fa77ae00800..1fbee7a2df63b99af23cd3deea1e442e7a1124a5 100644
--- a/webrtc/common_video/include/incoming_video_stream.h
+++ b/webrtc/common_video/include/incoming_video_stream.h
@@ -15,30 +15,20 @@
 
 #include "webrtc/base/criticalsection.h"
 #include "webrtc/base/platform_thread.h"
+#include "webrtc/base/task_queue.h"
 #include "webrtc/base/thread_annotations.h"
+#include "webrtc/base/thread_checker.h"
 #include "webrtc/common_video/video_render_frames.h"
 #include "webrtc/media/base/videosinkinterface.h"
 
 namespace webrtc {
 class EventTimerWrapper;
 
-
 class IncomingVideoStream : public rtc::VideoSinkInterface<VideoFrame> {
  public:
-  explicit IncomingVideoStream(bool disable_prerenderer_smoothing);
-  ~IncomingVideoStream();
-
-  // Overrides VideoSinkInterface
-  void OnFrame(const VideoFrame& video_frame) override;
-
-  // Callback for file recording, snapshot, ...
-  void SetExternalCallback(rtc::VideoSinkInterface<VideoFrame>* render_object);
-
-  // Start/Stop.
-  int32_t Start();
-  int32_t Stop();
-
-  int32_t SetExpectedRenderDelay(int32_t delay_ms);
+  IncomingVideoStream(int32_t delay_ms,
+                      rtc::VideoSinkInterface<VideoFrame>* callback);
+  ~IncomingVideoStream() override;
 
  protected:
   static bool IncomingVideoStreamThreadFun(void* obj);
@@ -49,26 +39,36 @@ class IncomingVideoStream : public rtc::VideoSinkInterface<VideoFrame> {
   enum { kEventMaxWaitTimeMs = 100 };
   enum { kFrameRatePeriodMs = 1000 };
 
-  void DeliverFrame(const VideoFrame& video_frame);
+  void OnFrame(const VideoFrame& video_frame) override;
+
+  rtc::ThreadChecker main_thread_checker_;
+  rtc::ThreadChecker render_thread_checker_;
+  rtc::ThreadChecker decoder_thread_checker_;
 
-  const bool disable_prerenderer_smoothing_;
-  // Critsects in allowed to enter order.
-  rtc::CriticalSection stream_critsect_;
-  rtc::CriticalSection thread_critsect_;
   rtc::CriticalSection buffer_critsect_;
-  // TODO(pbos): Make plain member and stop resetting this thread, just
-  // start/stoping it is enough.
-  std::unique_ptr<rtc::PlatformThread> incoming_render_thread_
-      GUARDED_BY(thread_critsect_);
+  rtc::PlatformThread incoming_render_thread_;
   std::unique_ptr<EventTimerWrapper> deliver_buffer_event_;
 
-  bool running_ GUARDED_BY(stream_critsect_);
-  rtc::VideoSinkInterface<VideoFrame>* external_callback_
-      GUARDED_BY(thread_critsect_);
-  const std::unique_ptr<VideoRenderFrames> render_buffers_
+  rtc::VideoSinkInterface<VideoFrame>* const external_callback_;
+  std::unique_ptr<VideoRenderFrames> render_buffers_
       GUARDED_BY(buffer_critsect_);
 };
 
+class IncomingVideoStreamNoSmoothing
+    : public rtc::VideoSinkInterface<VideoFrame> {
+ public:
+  explicit IncomingVideoStreamNoSmoothing(
+      rtc::VideoSinkInterface<VideoFrame>* callback);
+
+ private:
+  // Overrides VideoSinkInterface
+  void OnFrame(const VideoFrame& video_frame) override;
+
+  rtc::ThreadChecker decoder_thread_checker_;
+  rtc::VideoSinkInterface<VideoFrame>* const callback_;
+  rtc::TaskQueue queue_;
+};
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_VIDEO_INCLUDE_INCOMING_VIDEO_STREAM_H_