Deliver video frames on Android, on the decode thread.

webrtc/modules/video_coding/generic_decoder.h

Index: webrtc/modules/video_coding/generic_decoder.h
diff --git a/webrtc/modules/video_coding/generic_decoder.h b/webrtc/modules/video_coding/generic_decoder.h
index fcfea7740ea98e006e866fe3e153928c72bcb399..a6fe9ce8873ac6acff9894f6221a797153bca5e1 100644
--- a/webrtc/modules/video_coding/generic_decoder.h
+++ b/webrtc/modules/video_coding/generic_decoder.h
@@ -18,7 +18,6 @@
 #include "webrtc/modules/video_coding/include/video_codec_interface.h"
 #include "webrtc/modules/video_coding/timestamp_map.h"
 #include "webrtc/modules/video_coding/timing.h"
-#include "webrtc/rtc_base/criticalsection.h"
 #include "webrtc/rtc_base/thread_checker.h"
 
 namespace webrtc {
@@ -40,6 +39,7 @@ class VCMDecodedFrameCallback : public DecodedImageCallback {
  public:
   VCMDecodedFrameCallback(VCMTiming* timing, Clock* clock);
   ~VCMDecodedFrameCallback() override;
+
   void SetUserReceiveCallback(VCMReceiveCallback* receiveCallback);
   VCMReceiveCallback* UserReceiveCallback();
 
@@ -59,7 +59,7 @@ class VCMDecodedFrameCallback : public DecodedImageCallback {
 
  private:
   rtc::ThreadChecker construction_thread_;
-  // Protect |_timestampMap|.
+  rtc::ThreadChecker decoder_thread_;
   Clock* const _clock;
   // This callback must be set before the decoder thread starts running
   // and must only be unset when external threads (e.g decoder thread)
@@ -67,10 +67,9 @@ class VCMDecodedFrameCallback : public DecodedImageCallback {
   // while there are more than one threads involved, it must be set
   // from the same thread, and therfore a lock is not required to access it.
   VCMReceiveCallback* _receiveCallback = nullptr;
-  VCMTiming* _timing;
-  rtc::CriticalSection lock_;
-  VCMTimestampMap _timestampMap GUARDED_BY(lock_);
-  uint64_t _lastReceivedPictureID;
+  VCMTiming* _timing ACCESS_ON(decoder_thread_);
+  VCMTimestampMap _timestampMap ACCESS_ON(decoder_thread_);
+  uint64_t _lastReceivedPictureID ACCESS_ON(decoder_thread_);
   int64_t ntp_offset_;
 };
 
@@ -96,18 +95,24 @@ class VCMGenericDecoder {
   */
   int32_t RegisterDecodeCompleteCallback(VCMDecodedFrameCallback* callback);
 
-  bool External() const;
   bool PrefersLateDecoding() const;
   bool IsSameDecoder(VideoDecoder* decoder) const {
     return decoder_.get() == decoder;
   }
 
+#if defined(WEBRTC_ANDROID)
+  // See https://bugs.chromium.org/p/webrtc/issues/detail?id=7361
+  void PollDecodedFrames();
+#endif
+
  private:
-  VCMDecodedFrameCallback* _callback;
-  VCMFrameInformation _frameInfos[kDecoderFrameMemoryLength];
-  uint32_t _nextFrameInfoIdx;
+  rtc::ThreadChecker decoder_thread_;
+  VCMDecodedFrameCallback* _callback ACCESS_ON(decoder_thread_);
+  VCMFrameInformation _frameInfos[kDecoderFrameMemoryLength] ACCESS_ON(
+      decoder_thread_);
+  uint32_t _nextFrameInfoIdx ACCESS_ON(decoder_thread_);
   std::unique_ptr<VideoDecoder> decoder_;
-  VideoCodecType _codecType;
+  VideoCodecType _codecType ACCESS_ON(decoder_thread_);
   const bool _isExternal;
   VideoContentType _last_keyframe_content_type;
 };