Reland of 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..778cc1d5994f1b8bcb01a76cf4e718830f81a7b3 100644
--- a/webrtc/modules/video_coding/codecs/test/videoprocessor.h
+++ b/webrtc/modules/video_coding/codecs/test/videoprocessor.h
@@ -250,6 +250,11 @@
       RTC_NOTREACHED();
       return -1;
     }
+    void Decoded(VideoFrame& frame,
+                 rtc::Optional<int32_t> decode_time_ms,
+                 rtc::Optional<uint8_t> qp) override {
+      RTC_NOTREACHED();
+    }
 
    private:
     VideoProcessorImpl* video_processor_;