Fix virtual/override/final usage in Source/core/{animation,css,style}/.

Source/core/css/CSSFontFaceRule.h

Index: Source/core/css/CSSFontFaceRule.h
diff --git a/Source/core/css/CSSFontFaceRule.h b/Source/core/css/CSSFontFaceRule.h
index 7638a8e67cb7052825c50f286b45b3d08e71e955..aaa67c7b0eb562ec18011a6f9123c6b428c8caa0 100644
--- a/Source/core/css/CSSFontFaceRule.h
+++ b/Source/core/css/CSSFontFaceRule.h
@@ -39,10 +39,10 @@ public:
         return adoptRefWillBeNoop(new CSSFontFaceRule(rule, sheet));
     }
 
-    virtual ~CSSFontFaceRule();
+    ~CSSFontFaceRule() override;
 
-    virtual String cssText() const override;
-    virtual void reattach(StyleRuleBase*) override;
+    String cssText() const override;
+    void reattach(StyleRuleBase*) override;
 
     CSSStyleDeclaration* style() const;
 
@@ -53,7 +53,7 @@ public:
 private:
     CSSFontFaceRule(StyleRuleFontFace*, CSSStyleSheet* parent);
 
-    virtual CSSRule::Type type() const override { return FONT_FACE_RULE; }
+    CSSRule::Type type() const override { return FONT_FACE_RULE; }
 
     RefPtrWillBeMember<StyleRuleFontFace> m_fontFaceRule;
     mutable RefPtrWillBeMember<StyleRuleCSSStyleDeclaration> m_propertiesCSSOMWrapper;