ui: Fix clang warnings about missing virtual and OVERRIDE annotations.

ui/base/resource/resource_bundle.cc

 // Copyright (c) 2012 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 "ui/base/resource/resource_bundle.h"
 
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
@@ skipping 61 matching lines @@
 // will show the scaled image blended with red instead.
 class ResourceBundle::ResourceBundleImageSource : public gfx::ImageSkiaSource {
  public:
   ResourceBundleImageSource(int resource_id, const gfx::Size& size_in_dip)
       : resource_id_(resource_id),
         size_in_dip_(size_in_dip) {
   }
   virtual ~ResourceBundleImageSource() {}
 
   // gfx::ImageSkiaSource overrides:
-  virtual gfx::ImageSkiaRep GetImageForScale(ui::ScaleFactor scale_factor) {
+  virtual gfx::ImageSkiaRep GetImageForScale(
+      ui::ScaleFactor scale_factor) OVERRIDE {
     ResourceBundle& rb = ResourceBundle::GetSharedInstance();
 
     scoped_ptr<SkBitmap> result(rb.LoadBitmap(resource_id_, scale_factor));
     gfx::Size size_in_pixel =
         size_in_dip_.Scale(ui::GetScaleFactorScale(scale_factor));
 
     if (scale_factor == SCALE_FACTOR_200P &&
         (!result.get() ||
          result->width() != size_in_pixel.width() ||
          result->height() != size_in_pixel.height())) {
@@ skipping 538 matching lines @@
     SkBitmap bitmap;
     bitmap.setConfig(SkBitmap::kARGB_8888_Config, 32, 32);
     bitmap.allocPixels();
     bitmap.eraseARGB(255, 255, 0, 0);
     empty_image_ = gfx::Image(bitmap);
   }
   return empty_image_;
 }
 
 }  // namespace ui