Standardize usage of virtual/override/final specifiers.

ui/views/controls/button/label_button_border.h

Index: ui/views/controls/button/label_button_border.h
diff --git a/ui/views/controls/button/label_button_border.h b/ui/views/controls/button/label_button_border.h
index 936c89878a4d1632ecc94b05c042f49a8f3f152c..05d70f06d5b5401fd79ab34abf22a430a655e20f 100644
--- a/ui/views/controls/button/label_button_border.h
+++ b/ui/views/controls/button/label_button_border.h
@@ -19,14 +19,14 @@ namespace views {
 class VIEWS_EXPORT LabelButtonBorder : public Border {
  public:
   explicit LabelButtonBorder(Button::ButtonStyle style);
-  virtual ~LabelButtonBorder();
+  ~LabelButtonBorder() override;
 
   Button::ButtonStyle style() const { return style_; }
 
   // Overridden from Border:
-  virtual void Paint(const View& view, gfx::Canvas* canvas) override;
-  virtual gfx::Insets GetInsets() const override;
-  virtual gfx::Size GetMinimumSize() const override;
+  void Paint(const View& view, gfx::Canvas* canvas) override;
+  gfx::Insets GetInsets() const override;
+  gfx::Size GetMinimumSize() const override;
 
   void set_insets(const gfx::Insets& insets) { insets_ = insets; }