Add QP sum stats for received streams.

webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h

Index: webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h
diff --git a/webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h b/webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h
index 7e2076ccdc1cff805dcf087cfbdb805c6a8079f8..bbf3098b655f1f18a4aa535841de5e5a3975dcfa 100644
--- a/webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h
+++ b/webrtc/modules/video_coding/include/mock/mock_video_codec_interface.h
@@ -57,6 +57,10 @@ class MockDecodedImageCallback : public DecodedImageCallback {
   MOCK_METHOD2(Decoded,
                int32_t(VideoFrame& decodedImage,  // NOLINT
                        int64_t decode_time_ms));
+  MOCK_METHOD3(Decoded,
+               void(VideoFrame& decodedImage,  // NOLINT
+                    rtc::Optional<int32_t> decode_time_ms,
+                    rtc::Optional<uint8_t> qp));
   MOCK_METHOD1(ReceivedDecodedReferenceFrame,
                int32_t(const uint64_t pictureId));
   MOCK_METHOD1(ReceivedDecodedFrame, int32_t(const uint64_t pictureId));