Clean up virtual functions in css/

Source/core/css/CSSFilterRule.h

Index: Source/core/css/CSSFilterRule.h
diff --git a/Source/core/css/CSSFilterRule.h b/Source/core/css/CSSFilterRule.h
index 3a9ba7295818b033a9e9c191f1a57dd04c26417e..2cb04ee5b29f6b608b5d4705c7c4d20d966febfa 100644
--- a/Source/core/css/CSSFilterRule.h
+++ b/Source/core/css/CSSFilterRule.h
@@ -49,7 +49,6 @@ public:
 
     virtual ~CSSFilterRule();
 
-    virtual CSSRule::Type type() const override { return WEBKIT_FILTER_RULE; }
     virtual String cssText() const override;
     virtual void reattach(StyleRuleBase*) override;
 
@@ -60,6 +59,8 @@ public:
 private:
     CSSFilterRule(StyleRuleFilter*, CSSStyleSheet* parent);
 
+    virtual CSSRule::Type type() const override { return WEBKIT_FILTER_RULE; }
+
     RefPtrWillBeMember<StyleRuleFilter> m_filterRule;
     mutable RefPtrWillBeMember<StyleRuleCSSStyleDeclaration> m_propertiesCSSOMWrapper;
 };