Add VideoCodec::PreferDecodeLate

webrtc/video_decoder.h

Index: webrtc/video_decoder.h
diff --git a/webrtc/video_decoder.h b/webrtc/video_decoder.h
index 2822677868db4f3aa531e1e7bd4bf3c2dc6ff176..d1e65fee95b4880a464adb68750aa55d395c73c6 100644
--- a/webrtc/video_decoder.h
+++ b/webrtc/video_decoder.h
@@ -63,6 +63,13 @@ class VideoDecoder {
 
   virtual int32_t Release() = 0;
   virtual int32_t Reset() = 0;
+
+  // Returns true if the currently active decoder only has one output buffer.
+  // That means that frames must be decoded near the render times stamp since
+  // multiple frames can not be decoded ahead of time.
+  virtual bool HasOnlyOneOutputBuffer() const {
+    return false;
+  }
 };
 
 // Class used to wrap external VideoDecoders to provide a fallback option on
@@ -87,6 +94,7 @@ class VideoDecoderSoftwareFallbackWrapper : public webrtc::VideoDecoder {
 
   int32_t Release() override;
   int32_t Reset() override;
+  bool HasOnlyOneOutputBuffer() const override;
 
  private:
   bool InitFallbackDecoder();