UMA histograms to measure whether / how long blank text is rendered for loading web fonts

Source/core/css/FontFace.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 521 matching lines @@
 
         if (source) {
 #if ENABLE(SVG_FONTS)
             source->setSVGFontFaceElement(item->svgFontFaceElement());
 #endif
             m_cssFontFace->addSource(source.release());
         }
     }
 }
 
+bool FontFace::hadBlankText() const
+{
+    return m_cssFontFace->hadBlankText();
+}
+
 } // namespace WebCore