Primary FontData of FontFallbackList should have space character

Source/platform/fonts/FontFallbackList.cpp

 /*
  * Copyright (C) 2006 Apple Computer, 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
@@ skipping 90 matching lines @@
         if (m_fontList[i]->isCustomFont() && m_fontList[i]->isLoading()) {
             m_loadingCustomFonts = true;
             return true;
         }
     }
     return false;
 }
 
 const FontData* FontFallbackList::primaryFontData(const FontDescription& fontDescription) const
 {
+    bool shouldLoadCustomFont = true;
+
     for (unsigned fontIndex = 0; ; ++fontIndex) {
         const FontData* fontData = fontDataAt(fontDescription, fontIndex);
         if (!fontData) {
             // All fonts are custom fonts and are loading. Return the first FontData.
             // FIXME: Correct fallback to the default font.
             return fontDataAt(fontDescription, 0);
         }
 
+        if (fontData->isSegmented() && !toSegmentedFontData(fontData)->containsCharacter(' '))
+            continue;
+
         // When a custom font is loading, we should use the correct fallback font to layout the text.
         // Here skip the temporary font for the loading custom font which may not act as the correct fallback font.
         if (!fontData->isLoadingFallback())
             return fontData;
 
         // Begin to load the first custom font if needed.
-        if (!fontIndex) {
+        if (shouldLoadCustomFont) {
+            shouldLoadCustomFont = false;
             const SimpleFontData* simpleFontData = fontData->fontDataForCharacter(' ');
             if (simpleFontData && simpleFontData->customFontData())
                 simpleFontData->customFontData()->beginLoadIfNeeded();
         }
     }
 }
 
 PassRefPtr<FontData> FontFallbackList::getFontData(const FontDescription& fontDescription, int& familyIndex) const
 {
     RefPtr<FontData> result;
@@ skipping 54 matching lines @@
     RefPtr<FontData> result = getFontData(fontDescription, m_familyIndex);
     if (result) {
         m_fontList.append(result);
         if (result->isLoading())
             m_loadingCustomFonts = true;
     }
     return result.get();
 }
 
 }