Fix virtual/override/final usage in Source/core/dom/.

Source/core/dom/FirstLetterPseudoElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 24 matching lines @@
 class LayoutTextFragment;
 
 class FirstLetterPseudoElement final : public PseudoElement {
     WTF_MAKE_NONCOPYABLE(FirstLetterPseudoElement);
 public:
     static PassRefPtrWillBeRawPtr<FirstLetterPseudoElement> create(Element* parent)
     {
         return adoptRefWillBeNoop(new FirstLetterPseudoElement(parent));
     }
 
-    virtual ~FirstLetterPseudoElement();
+    ~FirstLetterPseudoElement() override;
 
     static LayoutObject* firstLetterTextLayoutObject(const Element&);
     static unsigned firstLetterLength(const String&);
 
     void setRemainingTextLayoutObject(LayoutTextFragment*);
     LayoutTextFragment* remainingTextLayoutObject() const { return m_remainingTextLayoutObject; }
 
     void updateTextFragments();
 
-    virtual void attach(const AttachContext& = AttachContext()) override;
-    virtual void detach(const AttachContext& = AttachContext()) override;
+    void attach(const AttachContext& = AttachContext()) override;
+    void detach(const AttachContext& = AttachContext()) override;
 
 private:
     explicit FirstLetterPseudoElement(Element*);
 
-    virtual void didRecalcStyle(StyleRecalcChange) override;
+    void didRecalcStyle(StyleRecalcChange) override;
 
     void attachFirstLetterTextLayoutObjects();
     ComputedStyle* styleForFirstLetter(LayoutObject*);
 
     LayoutTextFragment* m_remainingTextLayoutObject;
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(FirstLetterPseudoElement, isFirstLetterPseudoElement());
 
 } // namespace blink
 
 #endif // FirstLetterPseudoElement_h