Add QP sum stats for received streams.

webrtc/modules/video_coding/codecs/test/videoprocessor.h

Index: webrtc/modules/video_coding/codecs/test/videoprocessor.h
diff --git a/webrtc/modules/video_coding/codecs/test/videoprocessor.h b/webrtc/modules/video_coding/codecs/test/videoprocessor.h
index a217b1132ea378dc6053867a82a39c26366c5ce4..4be111ac4eade57b0e2040f4c377d4d4de37acbe 100644
--- a/webrtc/modules/video_coding/codecs/test/videoprocessor.h
+++ b/webrtc/modules/video_coding/codecs/test/videoprocessor.h
@@ -250,6 +250,12 @@ class VideoProcessorImpl : public VideoProcessor {
       RTC_NOTREACHED();
       return -1;
     }
+    int32_t Decoded(VideoFrame& frame,
+                    int64_t decode_time_ms,
+                    int qp) override {
+      RTC_NOTREACHED();
+      return -1;
+    }
 
    private:
     VideoProcessorImpl* video_processor_;