Remove source file writer from VideoProcessor.

webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc

Index: webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc
diff --git a/webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc b/webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc
index cb1578bce04a337ba8b5ebe78c16f27ee457421f..c57b822ee4ff981f470dfc7375b560bcc1b56361 100644
--- a/webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc
+++ b/webrtc/modules/video_coding/codecs/test/plot_videoprocessor_integrationtest.cc
@@ -35,7 +35,6 @@ const bool kBatchMode = true;
 const float kPacketLoss = 0.0f;
 
 const VisualizationParams kVisualizationParams = {
-    false,  // save_source_y4m
     false,  // save_encoded_ivf
     false,  // save_decoded_y4m
 };