Pass camera facing to WebKit

content/renderer/media/media_stream_video_source.h

Index: content/renderer/media/media_stream_video_source.h
diff --git a/content/renderer/media/media_stream_video_source.h b/content/renderer/media/media_stream_video_source.h
index 666aced76582e7a44d0f4ec7286d44071300ace0..c68d96c0c556c782ab3d8f77998cb91bfd009c44 100644
--- a/content/renderer/media/media_stream_video_source.h
+++ b/content/renderer/media/media_stream_video_source.h
@@ -89,6 +89,10 @@ class CONTENT_EXPORT MediaStreamVideoSource
     return weak_factory_.GetWeakPtr();
   }
 
+  virtual media::VideoFacingMode GetVideoFacing() {
+    return media::VideoFacingMode::USER;
+  }
+
  protected:
   void DoStopSource() override;