CSSSegmentedFontFaceCache should not know about Document.

Source/core/css/CSSSegmentedFontFaceCache.h

 /*
  * Copyright (C) 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Google 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 27 matching lines @@
 class CSSSegmentedFontFace;
 class FontDescription;
 class StyleRuleFontFace;
 
 class CSSSegmentedFontFaceCache {
 public:
     CSSSegmentedFontFaceCache();
 
     // FIXME: Remove CSSFontSelector as argument. Passing CSSFontSelector here is
     // a result of egregious spaghettification in CSSFontFace/FontFaceSet.
-    void addFontFaceRule(CSSFontSelector*, const StyleRuleFontFace*);
-    void removeFontFaceRule(const StyleRuleFontFace*);
-    CSSSegmentedFontFace* getFontFace(const FontDescription&, const AtomicString& family);
+    void add(CSSFontSelector*, const StyleRuleFontFace*, PassRefPtr<CSSFontFace>);
+    void remove(const StyleRuleFontFace*);
+    // FIXME: It's sort of weird that add/remove uses StyleRuleFontFace* as key,
+    // but this function uses FontDescription/family pair.
+    CSSSegmentedFontFace* get(const FontDescription&, const AtomicString& family);
 
     unsigned version() const { return m_version; }
 
 private:
     typedef HashMap<unsigned, RefPtr<CSSSegmentedFontFace> > TraitsMap;
     typedef HashMap<String, OwnPtr<TraitsMap>, CaseFoldingHash> FamilyToTraitsMap;
     typedef HashMap<const StyleRuleFontFace*, RefPtr<CSSFontFace> > StyleRuleToFontFace;
     FamilyToTraitsMap m_fontFaces;
     FamilyToTraitsMap m_fonts;
     StyleRuleToFontFace m_styleRuleToFontFace;
 
     // FIXME: See if this could be ditched
     // Used to compare Font instances, and the usage seems suspect.
     unsigned m_version;
 };
 
 }
 
 #endif