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

Source/core/html/HTMLFrameOwnerElement.h

 /*
  * Copyright (C) 2006, 2007, 2009 Apple Inc. 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 22 matching lines @@
 
 class LocalDOMWindow;
 class ExceptionState;
 class Frame;
 class LayoutPart;
 class Widget;
 
 class CORE_EXPORT HTMLFrameOwnerElement : public HTMLElement, public FrameOwner {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(HTMLFrameOwnerElement);
 public:
-    virtual ~HTMLFrameOwnerElement();
+    ~HTMLFrameOwnerElement() override;
 
     Frame* contentFrame() const { return m_contentFrame; }
     DOMWindow* contentWindow() const;
     Document* contentDocument() const;
 
     void setContentFrame(Frame&);
     void clearContentFrame();
 
     virtual void disconnectContentFrame();
 
@@ skipping 29 matching lines @@
 
     DECLARE_VIRTUAL_TRACE();
 
 protected:
     HTMLFrameOwnerElement(const QualifiedName& tagName, Document&);
     void setSandboxFlags(SandboxFlags);
 
     bool loadOrRedirectSubframe(const KURL&, const AtomicString& frameName, bool lockBackForwardList);
 
 private:
-    virtual bool isKeyboardFocusable() const override;
-    virtual bool isFrameOwnerElement() const override final { return true; }
+    bool isKeyboardFocusable() const override;
+    bool isFrameOwnerElement() const final { return true; }
 
     RawPtrWillBeMember<Frame> m_contentFrame;
     RefPtrWillBeMember<Widget> m_widget;
     SandboxFlags m_sandboxFlags;
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(HTMLFrameOwnerElement, isFrameOwnerElement());
 
 class SubframeLoadingDisabler {
     STACK_ALLOCATED();
@@ skipping 24 matching lines @@
     static WillBeHeapHashCountedSet<RawPtrWillBeMember<Node>>& disabledSubtreeRoots();
 
     RawPtrWillBeMember<Node> m_root;
 };
 
 DEFINE_TYPE_CASTS(HTMLFrameOwnerElement, FrameOwner, owner, owner->isLocal(), owner.isLocal());
 
 } // namespace blink
 
 #endif // HTMLFrameOwnerElement_h