Standardize usage of virtual/override/final in extensions/

extensions/browser/image_loader.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_IMAGE_LOADER_H_
 #define EXTENSIONS_BROWSER_IMAGE_LOADER_H_
 
 #include <set>
 
 #include "base/callback_forward.h"
@@ skipping 55 matching lines @@
     ui::ScaleFactor scale_factor;
   };
 
   struct LoadResult;
 
   // Returns the instance for the given |context| or NULL if none. This is
   // a convenience wrapper around ImageLoaderFactory::GetForBrowserContext.
   static ImageLoader* Get(content::BrowserContext* context);
 
   ImageLoader();
-  virtual ~ImageLoader();
+  ~ImageLoader() override;
 
   // Specify image resource to load. If the loaded image is larger than
   // |max_size| it will be resized to those dimensions. IMPORTANT NOTE: this
   // function may call back your callback synchronously (ie before it returns)
   // if the image was found in the cache.
   // Note this method loads a raw bitmap from the resource. All sizes given are
   // assumed to be in pixels.
   void LoadImageAsync(const extensions::Extension* extension,
                       const ExtensionResource& resource,
                       const gfx::Size& max_size,
@@ skipping 25 matching lines @@
                                 const std::vector<LoadResult>& load_result);
 
   base::WeakPtrFactory<ImageLoader> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ImageLoader);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_IMAGE_LOADER_H_