Use unicode-range to prevent unnecessary @font-face donwnloads

Source/core/css/CSSFontFace.cpp

 /*
  * Copyright (C) 2007, 2008, 2011 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 49 matching lines @@
     source->setFontFace(this);
     m_sources.append(source);
 }
 
 void CSSFontFace::setSegmentedFontFace(CSSSegmentedFontFace* segmentedFontFace)
 {
     ASSERT(!m_segmentedFontFace);
     m_segmentedFontFace = segmentedFontFace;
 }
 
+void CSSFontFace::beginLoadingFontSoon(FontResource* resource)
+{
+    if (!m_segmentedFontFace)
+        return;
+
+    CSSFontSelector* fontSelector = m_segmentedFontFace->fontSelector();
+    fontSelector->beginLoadingFontSoon(resource);
+
+    if (m_loadState == NotLoaded)
+        setLoadState(Loading);
+}
+
 void CSSFontFace::fontLoaded(CSSFontFaceSource* source)
 {
     if (source != m_activeSource)
         return;
 
     // FIXME: Can we assert that m_segmentedFontFace is non-null? That may
     // require stopping in-progress font loading when the last
     // CSSSegmentedFontFace is removed.
     if (!m_segmentedFontFace)
         return;
@@ skipping 13 matching lines @@
 
 PassRefPtr<SimpleFontData> CSSFontFace::getFontData(const FontDescription& fontDescription, bool syntheticBold, bool syntheticItalic)
 {
     m_activeSource = 0;
     if (!isValid())
         return 0;
 
     ASSERT(m_segmentedFontFace);
     CSSFontSelector* fontSelector = m_segmentedFontFace->fontSelector();
 
-    if (m_loadState == NotLoaded)
-        setLoadState(Loading);
-
     size_t size = m_sources.size();
     for (size_t i = 0; i < size; ++i) {
         if (RefPtr<SimpleFontData> result = m_sources[i]->getFontData(fontDescription, syntheticBold, syntheticItalic, fontSelector)) {
             m_activeSource = m_sources[i].get();
+            if (m_loadState == NotLoaded && (m_sources[i]->isLoading() || m_sources[i]->isLoaded()))
+                setLoadState(Loading);
             if (m_loadState == Loading && m_sources[i]->isLoaded())
                 setLoadState(Loaded);
             return result.release();
         }
     }
 
+    if (m_loadState == NotLoaded)
+        setLoadState(Loading);
     if (m_loadState == Loading)
         setLoadState(Error);
     return 0;
 }
 
 void CSSFontFace::willUseFontData(const FontDescription& fontDescription)
 {
     if (m_loadState != NotLoaded)
         return;
 
@@ skipping 39 matching lines @@
     size_t size = m_sources.size();
     for (size_t i = 0; i < size; i++) {
         if (m_sources[i]->isSVGFontFaceSource())
             return true;
     }
     return false;
 }
 #endif
 
 }