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

Source/core/dom/TagCollection.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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 26 matching lines @@
         ASSERT(namespaceURI != starAtom);
         return adoptRefWillBeNoop(new TagCollection(rootNode, TagCollectionType, namespaceURI, localName));
     }
 
     static PassRefPtrWillBeRawPtr<TagCollection> create(ContainerNode& rootNode, CollectionType type, const AtomicString& localName)
     {
         ASSERT_UNUSED(type, type == TagCollectionType);
         return adoptRefWillBeNoop(new TagCollection(rootNode, TagCollectionType, starAtom, localName));
     }
 
-    virtual ~TagCollection();
+    ~TagCollection() override;
 
     bool elementMatches(const Element&) const;
 
 protected:
     TagCollection(ContainerNode& rootNode, CollectionType, const AtomicString& namespaceURI, const AtomicString& localName);
 
     AtomicString m_namespaceURI;
     AtomicString m_localName;
 };
 
 DEFINE_TYPE_CASTS(TagCollection, LiveNodeListBase, collection, collection->type() == TagCollectionType, collection.type() == TagCollectionType);
 
 } // namespace blink
 
 #endif // TagCollection_h