Remove dead methods from CSSStyleSheet and StyleSheetContents.

sky/engine/core/css/StyleSheetContents.h

Index: sky/engine/core/css/StyleSheetContents.h
diff --git a/sky/engine/core/css/StyleSheetContents.h b/sky/engine/core/css/StyleSheetContents.h
index 3ee88c4905da985c242e927de66a516dcde4c254..5419f26f39b95be441ff92c4515c76309d760d3a 100644
--- a/sky/engine/core/css/StyleSheetContents.h
+++ b/sky/engine/core/css/StyleSheetContents.h
@@ -53,17 +53,12 @@ public:
     const CSSParserContext& parserContext() const { return m_parserContext; }
 
     bool parseString(const String&);
-    bool parseStringAtPosition(const String&, const TextPosition&, bool);
 
     void parserAppendRule(PassRefPtr<StyleRuleBase>);
     void parserSetUsesRemUnits(bool b) { m_usesRemUnits = b; }
 
-    // Rules other than @charset and @import.
     const Vector<RefPtr<StyleRuleBase> >& childRules() const { return m_childRules; }
 
-    unsigned ruleCount() const;
-    StyleRuleBase* ruleAt(unsigned index) const;
-
     bool usesRemUnits() const { return m_usesRemUnits; }
 
     void registerClient(CSSStyleSheet*);