Standardize usage of virtual/override/final specifiers.

chrome/browser/ui/libgtk2ui/gtk2_border.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/libgtk2ui/gtk2_border.h"
 
 #include <gtk/gtk.h>
 
 #include "chrome/browser/ui/libgtk2ui/gtk2_ui.h"
 #include "chrome/browser/ui/libgtk2ui/gtk2_util.h"
@@ skipping 26 matching lines @@
                         const bool focused,
                         const bool call_to_action,
                         const gfx::Size& size)
       : gtk2_ui_(gtk2_ui),
         state_(state),
         focused_(focused),
         call_to_action_(call_to_action),
         size_(size) {
   }
 
-  virtual ~ButtonImageSkiaSource() {
-  }
+  ~ButtonImageSkiaSource() override {}
 
-  virtual gfx::ImageSkiaRep GetImageForScale(float scale) override {
+  gfx::ImageSkiaRep GetImageForScale(float scale) override {
     int w = size_.width() * scale;
     int h = size_.height() * scale;
     return gfx::ImageSkiaRep(
         gtk2_ui_->DrawGtkButtonBorder(state_, focused_, call_to_action_, w, h),
         scale);
   }
 
  private:
   const Gtk2UI* gtk2_ui_;
   const GtkStateType state_;
@@ skipping 91 matching lines @@
                                     focused,
                                     call_to_action,
                                     rect.size()),
           rect.size());
     }
     canvas->DrawImageInt(*image, rect.x(), rect.y());
   }
 }
 
 }  // namespace libgtk2ui