Spec compliant video constraints for getUserMedia behind flag.

content/renderer/media/pepper_to_video_track_adapter.cc

Index: content/renderer/media/pepper_to_video_track_adapter.cc
diff --git a/content/renderer/media/pepper_to_video_track_adapter.cc b/content/renderer/media/pepper_to_video_track_adapter.cc
index 5282026afc7d7bed9067dbe2be549a4b547411b3..7e08f24aa4c1c35951cec24798473570e8bdac70 100644
--- a/content/renderer/media/pepper_to_video_track_adapter.cc
+++ b/content/renderer/media/pepper_to_video_track_adapter.cc
@@ -262,13 +262,9 @@ bool PepperToVideoTrackAdapter::Open(MediaStreamRegistryInterface* registry,
                            false /* remote */);
   webkit_source.setExtraData(writer);
 
-  blink::WebMediaConstraints constraints;
-  constraints.initialize();
   bool track_enabled = true;
-
   stream.addTrack(MediaStreamVideoTrack::CreateVideoTrack(
-      writer, constraints, MediaStreamVideoSource::ConstraintsCallback(),
-      track_enabled));
+      writer, MediaStreamVideoSource::ConstraintsCallback(), track_enabled));
 
   *frame_writer = new PpFrameWriterProxy(writer->AsWeakPtr());
   return true;