Change FontFaceSet#check() behavior when no matched font-face

Source/core/css/CSSFontSelector.h

 /*
  * 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 39 matching lines @@
     static PassRefPtrWillBeRawPtr<CSSFontSelector> create(Document* document)
     {
         return adoptRefWillBeNoop(new CSSFontSelector(document));
     }
     virtual ~CSSFontSelector();
 
     virtual unsigned version() const OVERRIDE { return m_fontFaceCache.version(); }
 
     virtual PassRefPtr<FontData> getFontData(const FontDescription&, const AtomicString&) OVERRIDE;
     virtual void willUseFontData(const FontDescription&, const AtomicString& family, UChar32) OVERRIDE;
+    bool isPlatformFontAvailable(const FontDescription&, const AtomicString& family);
 
 #if !ENABLE(OILPAN)
     void clearDocument();
 #endif
 
     void fontFaceInvalidated();
 
     // FontCacheClient implementation
     virtual void fontCacheInvalidated() OVERRIDE;
 
@@ skipping 21 matching lines @@
     FontFaceCache m_fontFaceCache;
     WillBeHeapHashSet<RawPtrWillBeWeakMember<CSSFontSelectorClient> > m_clients;
 
     RefPtrWillBeMember<FontLoader> m_fontLoader;
     GenericFontFamilySettings m_genericFontFamilySettings;
 };
 
 } // namespace WebCore
 
 #endif // CSSFontSelector_h