Clean up virtual functions in css/

Source/core/css/CSSMediaRule.h

Index: Source/core/css/CSSMediaRule.h
diff --git a/Source/core/css/CSSMediaRule.h b/Source/core/css/CSSMediaRule.h
index e6d3cfe7bc61deb70c2214b4eb39003298237cec..8a19ce3456608a006c9935d9d69dc3f81bfca735 100644
--- a/Source/core/css/CSSMediaRule.h
+++ b/Source/core/css/CSSMediaRule.h
@@ -40,7 +40,6 @@ public:
 
     virtual ~CSSMediaRule();
 
-    virtual CSSRule::Type type() const override { return MEDIA_RULE; }
     virtual void reattach(StyleRuleBase*) override;
     virtual String cssText() const override;
 
@@ -51,6 +50,8 @@ public:
 private:
     CSSMediaRule(StyleRuleMedia*, CSSStyleSheet*);
 
+    virtual CSSRule::Type type() const override { return MEDIA_RULE; }
+
     MediaQuerySet* mediaQueries() const;
 
     mutable RefPtrWillBeMember<MediaList> m_mediaCSSOMWrapper;