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

Source/core/platform/graphics/SimpleFontData.cpp

Index: Source/core/platform/graphics/SimpleFontData.cpp
diff --git a/Source/core/platform/graphics/SimpleFontData.cpp b/Source/core/platform/graphics/SimpleFontData.cpp
index 7276f15eea7fdf515f590afe3cdb671ab0e07bdb..9f838cef57cb3991c89f0eb7db58db0fd7529611 100644
--- a/Source/core/platform/graphics/SimpleFontData.cpp
+++ b/Source/core/platform/graphics/SimpleFontData.cpp
@@ -30,6 +30,7 @@
 #include "config.h"
 #include "core/platform/graphics/SimpleFontData.h"
 
+#include "core/css/CSSFontFaceSource.h"
 #include "core/platform/graphics/opentype/OpenTypeVerticalData.h"
 
 #include "wtf/MathExtras.h"
@@ -42,19 +43,21 @@ namespace WebCore {
 const float smallCapsFontSizeMultiplier = 0.7f;
 const float emphasisMarkFontSizeMultiplier = 0.5f;
 
-SimpleFontData::SimpleFontData(const FontPlatformData& platformData, bool isCustomFont, bool isLoading, bool isTextOrientationFallback)
+SimpleFontData::SimpleFontData(const FontPlatformData& platformData, bool isCustomFont, bool isLoadingFallback, bool isTextOrientationFallback)
     : m_maxCharWidth(-1)
     , m_avgCharWidth(-1)
     , m_platformData(platformData)
     , m_treatAsFixedPitch(false)
     , m_isCustomFont(isCustomFont)
-    , m_isLoading(isLoading)
+    , m_isLoadingFallback(isLoadingFallback)
     , m_isTextOrientationFallback(isTextOrientationFallback)
     , m_isBrokenIdeographFallback(false)
 #if ENABLE(OPENTYPE_VERTICAL)
     , m_verticalData(0)
 #endif
     , m_hasVerticalGlyphs(false)
+    , m_isUsed(false)

[eseidel, 2013/09/10 15:07:26]

We should make this name more explicit so that we know that it's only used for
custom fonts.

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

Now it's m_customFontData.isUsed.

+    , m_fontFaceSource(0)
 {
     platformInit();
     platformGlyphInit();
@@ -72,13 +75,15 @@ SimpleFontData::SimpleFontData(PassOwnPtr<AdditionalFontData> fontData, float fo
     , m_fontData(fontData)
     , m_treatAsFixedPitch(false)
     , m_isCustomFont(true)
-    , m_isLoading(false)
+    , m_isLoadingFallback(false)
     , m_isTextOrientationFallback(false)
     , m_isBrokenIdeographFallback(false)
 #if ENABLE(OPENTYPE_VERTICAL)
     , m_verticalData(0)
 #endif
     , m_hasVerticalGlyphs(false)
+    , m_isUsed(false)
+    , m_fontFaceSource(0)
 {
     m_fontData->initializeFontData(this, fontSize);
 }
@@ -226,6 +231,14 @@ PassRefPtr<SimpleFontData> SimpleFontData::brokenIdeographFontData() const
     return m_derivedFontData->brokenIdeograph;
 }
 
+void SimpleFontData::beginLoadIfNeeded() const
+{
+    if (!m_isUsed && m_isLoadingFallback && m_fontFaceSource) {
+        m_isUsed = true;
+        m_fontFaceSource->beginLoadingFontSoon();
+    }
+}
+
 #ifndef NDEBUG
 String SimpleFontData::description() const
 {