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

Source/core/platform/graphics/FontFallbackList.cpp

Index: Source/core/platform/graphics/FontFallbackList.cpp
diff --git a/Source/core/platform/graphics/FontFallbackList.cpp b/Source/core/platform/graphics/FontFallbackList.cpp
index e3405e58e06a26528442f22738945c7f437445d0..a68e8ba94307be88aa7e6dae2ce01d946d256566 100644
--- a/Source/core/platform/graphics/FontFallbackList.cpp
+++ b/Source/core/platform/graphics/FontFallbackList.cpp
@@ -88,6 +88,21 @@ void FontFallbackList::determinePitch(const Font* font) const
     }
 }
 
+bool FontFallbackList::loadingCustomFonts() const
+{
+    if (m_loadingCustomFonts)
+        return true;
+
+    unsigned numFonts = m_fontList.size();
+    for (unsigned i = 0; i < numFonts; ++i) {
+        if (m_fontList[i]->isCustomFont() && m_fontList[i]->isLoading()) {
+            m_loadingCustomFonts = true;

[dglazkov, 2013/09/10 15:26:41]

This smells wrong. Why does a const getter modify state? It seems that we're
just using m_loadingCustomFonts as a memoizer for this function. I think we
should split these concerns up: one method to ensure m_loadingCustomFonts, one
to query it. The fontDataAt does sort of the same thing.

[Kunihiko Sakamoto, 2013/09/11 13:28:09]

Now FontData in m_fontList can change its loading state by getting used, so we
cannot simply calculate m_loadingCustomFonts once at first. Maybe we should make
this function non-const?

+            return true;
+        }
+    }
+    return false;
+}
+
 const FontData* FontFallbackList::fontDataAt(const Font* font, unsigned realizedFontIndex) const
 {
     if (realizedFontIndex < m_fontList.size())