Remove source file writer from VideoProcessor.

webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc

Index: webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc
diff --git a/webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc b/webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc
index 1b90c67899f29213f78574611ceb4d483b1e16ec..95d1b1c7596e7956aab7ff2221fb544fe2f6133d 100644
--- a/webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc
+++ b/webrtc/modules/video_coding/codecs/tools/video_quality_measurement.cc
@@ -508,8 +508,8 @@ int main(int argc, char* argv[]) {
   }
   webrtc::test::VideoProcessor* processor = new webrtc::test::VideoProcessor(
       encoder, decoder, &frame_reader, &frame_writer, &packet_manipulator,
-      config, &stats, nullptr /* source_frame_writer */,
-      nullptr /* encoded_frame_writer */, nullptr /* decoded_frame_writer */);
+      config, &stats, nullptr /* encoded_frame_writer */,
+      nullptr /* decoded_frame_writer */);
   processor->Init();
 
   int frame_number = 0;