Fix virtual/override/final usage in Source/platform/.

Source/platform/scroll/ScrollbarThemeOverlay.h

 /*
  * 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 21 matching lines @@
 namespace blink {
 
 // This scrollbar theme is used to get overlay scrollbar for platforms other
 // than Mac. Mac's overlay scrollbars are in ScrollbarThemeMac*.
 class PLATFORM_EXPORT ScrollbarThemeOverlay : public ScrollbarTheme {
 public:
     enum HitTestBehavior { AllowHitTest, DisallowHitTest };
 
     ScrollbarThemeOverlay(int thumbThickness, int scrollbarMargin, HitTestBehavior);
     ScrollbarThemeOverlay(int thumbThickness, int scrollbarMargin, HitTestBehavior, Color);
-    virtual ~ScrollbarThemeOverlay() { }
+    ~ScrollbarThemeOverlay() override {}
 
-    virtual int scrollbarThickness(ScrollbarControlSize) override;
-    virtual int scrollbarMargin() const override;
-    virtual bool usesOverlayScrollbars() const override;
+    int scrollbarThickness(ScrollbarControlSize) override;
+    int scrollbarMargin() const override;
+    bool usesOverlayScrollbars() const override;
 
-    virtual int thumbPosition(ScrollbarThemeClient*) override;
-    virtual int thumbLength(ScrollbarThemeClient*) override;
+    int thumbPosition(ScrollbarThemeClient*) override;
+    int thumbLength(ScrollbarThemeClient*) override;
 
-    virtual bool hasButtons(ScrollbarThemeClient*) override { return false; };
-    virtual bool hasThumb(ScrollbarThemeClient*) override;
+    bool hasButtons(ScrollbarThemeClient*) override { return false; };
+    bool hasThumb(ScrollbarThemeClient*) override;
 
-    virtual IntRect backButtonRect(ScrollbarThemeClient*, ScrollbarPart, bool painting = false) override;
-    virtual IntRect forwardButtonRect(ScrollbarThemeClient*, ScrollbarPart, bool painting = false) override;
-    virtual IntRect trackRect(ScrollbarThemeClient*, bool painting = false) override;
-    virtual int thumbThickness(ScrollbarThemeClient*) override;
+    IntRect backButtonRect(ScrollbarThemeClient*, ScrollbarPart, bool painting = false) override;
+    IntRect forwardButtonRect(ScrollbarThemeClient*, ScrollbarPart, bool painting = false) override;
+    IntRect trackRect(ScrollbarThemeClient*, bool painting = false) override;
+    int thumbThickness(ScrollbarThemeClient*) override;
 
-    virtual void paintThumb(GraphicsContext*, ScrollbarThemeClient*, const IntRect&) override;
-    virtual ScrollbarPart hitTest(ScrollbarThemeClient*, const IntPoint&) override;
+    void paintThumb(GraphicsContext*, ScrollbarThemeClient*, const IntRect&) override;
+    ScrollbarPart hitTest(ScrollbarThemeClient*, const IntPoint&) override;
 
 private:
     int m_thumbThickness;
     int m_scrollbarMargin;
     HitTestBehavior m_allowHitTest;
     Color m_color;
     const bool m_useSolidColor;
 };
 
 } // namespace blink
 
 #endif