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

Source/core/layout/LayoutSearchField.h

 /*
  * Copyright (C) 2006, 2007, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 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
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 14 matching lines @@
 
 #include "core/layout/LayoutTextControlSingleLine.h"
 
 namespace blink {
 
 class HTMLInputElement;
 
 class LayoutSearchField final : public LayoutTextControlSingleLine {
 public:
     LayoutSearchField(HTMLInputElement*);
-    virtual ~LayoutSearchField();
+    ~LayoutSearchField() override;
 
 private:
-    virtual void centerContainerIfNeeded(LayoutBox*) const override;
-    virtual LayoutUnit computeControlLogicalHeight(LayoutUnit lineHeight, LayoutUnit nonContentHeight) const override;
-    virtual LayoutUnit computeLogicalHeightLimit() const override;
+    void centerContainerIfNeeded(LayoutBox*) const override;
+    LayoutUnit computeControlLogicalHeight(LayoutUnit lineHeight, LayoutUnit nonContentHeight) const override;
+    LayoutUnit computeLogicalHeightLimit() const override;
 
     Element* searchDecorationElement() const;
     Element* cancelButtonElement() const;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutSearchField, isTextField());
 
 }
 
 #endif // LayoutSearchField_h