extensions: Cleanup class/struct fwd declarations

extensions/browser/extension_icon_image.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_EXTENSION_ICON_IMAGE_H_
 #define EXTENSIONS_BROWSER_EXTENSION_ICON_IMAGE_H_
 
 #include <map>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "extensions/common/extension_icon_set.h"
 #include "ui/base/layout.h"
 #include "ui/gfx/image/image.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace content {
 class BrowserContext;
 }
 
 namespace extensions {
 class Extension;
 }
 
 namespace gfx {
-class Size;
 class Image;
 }
 
 namespace extensions {
 
 // A class that provides an ImageSkia for UI code to use. It handles extension
 // icon resource loading, screen scale factor change etc. UI code that uses
 // extension icon should host this class. In painting code, UI code paints with
 // the ImageSkia provided by this class. If the required extension icon resource
 // is not already present, this class tries to load it and calls its observer
@@ skipping 79 matching lines @@
   content::NotificationRegistrar registrar_;
 
   base::WeakPtrFactory<IconImage> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(IconImage);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_EXTENSION_ICON_IMAGE_H_