Fix virtual/override/final usage in the rest of Source/core/.

Source/core/page/PageSerializer.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 85 matching lines @@
 static const QualifiedName& frameOwnerURLAttributeName(const HTMLFrameOwnerElement& frameOwner)
 {
     // FIXME: We should support all frame owners including applets.
     return isHTMLObjectElement(frameOwner) ? HTMLNames::dataAttr : HTMLNames::srcAttr;
 }
 
 class SerializerMarkupAccumulator : public MarkupAccumulator {
     STACK_ALLOCATED();
 public:
     SerializerMarkupAccumulator(PageSerializer*, const Document&, WillBeHeapVector<RawPtrWillBeMember<Node>>&);
-    virtual ~SerializerMarkupAccumulator();
+    ~SerializerMarkupAccumulator() override;
 
 protected:
-    virtual void appendText(StringBuilder& out, Text&) override;
-    virtual bool shouldIgnoreAttribute(const Attribute&) override;
-    virtual void appendElement(StringBuilder& out, Element&, Namespaces*) override;
-    virtual void appendCustomAttributes(StringBuilder& out, const Element&, Namespaces*) override;
-    virtual void appendStartTag(Node&, Namespaces* = nullptr) override;
-    virtual void appendEndTag(const Element&) override;
+    void appendText(StringBuilder& out, Text&) override;
+    bool shouldIgnoreAttribute(const Attribute&) override;
+    void appendElement(StringBuilder& out, Element&, Namespaces*) override;
+    void appendCustomAttributes(StringBuilder& out, const Element&, Namespaces*) override;
+    void appendStartTag(Node&, Namespaces* = nullptr) override;
+    void appendEndTag(const Element&) override;
 
     const Document& document();
 
 private:
     PageSerializer* m_serializer;
     RawPtrWillBeMember<const Document> m_document;
 
     // FIXME: |PageSerializer| uses |m_nodes| for collecting nodes in document
     // included into serialized text then extracts image, object, etc. The size
     // of this vector isn't small for large document. It is better to use
@@ skipping 446 matching lines @@
 
     return fakeURL;
 }
 
 PageSerializer::Delegate* PageSerializer::delegate()
 {
     return m_delegate.get();
 }
 
 } // namespace blink