Standardize usage of virtual/override/final specifiers.

ui/views/controls/scrollbar/kennedy_scroll_bar.cc

Index: ui/views/controls/scrollbar/kennedy_scroll_bar.cc
diff --git a/ui/views/controls/scrollbar/kennedy_scroll_bar.cc b/ui/views/controls/scrollbar/kennedy_scroll_bar.cc
index 13a7823c2aedac525eadd71a52cd36ffc034ea58..bd4e0a060fada704fce4edfdc239eec046c94e6e 100644
--- a/ui/views/controls/scrollbar/kennedy_scroll_bar.cc
+++ b/ui/views/controls/scrollbar/kennedy_scroll_bar.cc
@@ -24,12 +24,12 @@ const SkColor kTrackHoverColor = SkColorSetARGB(32, 0, 0, 0);
 class KennedyScrollBarThumb : public BaseScrollBarThumb {
  public:
   explicit KennedyScrollBarThumb(BaseScrollBar* scroll_bar);
-  virtual ~KennedyScrollBarThumb();
+  ~KennedyScrollBarThumb() override;
 
  protected:
   // View overrides:
-  virtual gfx::Size GetPreferredSize() const override;
-  virtual void OnPaint(gfx::Canvas* canvas) override;
+  gfx::Size GetPreferredSize() const override;
+  void OnPaint(gfx::Canvas* canvas) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(KennedyScrollBarThumb);