Moves extension_icon_image and image_loader to extensions/browser

chrome/browser/extensions/extension_icon_image.h

-// 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.
-
-#ifndef CHROME_BROWSER_EXTENSIONS_EXTENSION_ICON_IMAGE_H_
-#define CHROME_BROWSER_EXTENSIONS_EXTENSION_ICON_IMAGE_H_
-
-#include <map>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/memory/weak_ptr.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_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 and be its observer. ExtensionIconImage
-// should be outlived by the observer. In painting code, UI code paints with the
-// ImageSkia provided by this class. If required extension icon resource is not
-// already present, this class tries to load it and calls its observer interface
-// when the image get updated. Until the resource is loaded, the UI code will be
-// provided with blank, transparent image.
-// If the requested resource doesn't exist or can't be loaded and a default
-// icon was supplied in the constructor, icon image will be updated with the
-// default icon's resource.
-// The default icon doesn't need to be supplied, but in that case, icon image
-// representation will be left blank if the resource loading fails.
-// If default icon is supplied, it is assumed that it contains or can
-// synchronously create (when |GetRepresentation| is called on it)
-// representations for all the scale factors supported by the current platform.
-// Note that |IconImage| is not thread safe.
-class IconImage : public content::NotificationObserver {
- public:
-  class Observer {
-   public:
-    // Invoked when a new image rep for an additional scale factor
-    // is loaded and added to |image|.
-    virtual void OnExtensionIconImageChanged(IconImage* image) = 0;
-
-   protected:
-    virtual ~Observer() {}
-  };
-
-  // |context| is required by the underlying implementation to retrieve the
-  // |ImageLoader| instance associated with the given context. |ImageLoader| is
-  // used to perform the asynchronous image load work.
-  IconImage(content::BrowserContext* context,
-            const Extension* extension,
-            const ExtensionIconSet& icon_set,
-            int resource_size_in_dip,
-            const gfx::ImageSkia& default_icon,
-            Observer* observer);
-  virtual ~IconImage();
-
-  const gfx::ImageSkia& image_skia() const { return image_skia_; }
-
- private:
-  class Source;
-
-  // Loads an image representation for the scale factor.
-  // If the representation gets loaded synchronously, it is returned by this
-  // method.
-  // If representation loading is asynchronous, an empty image
-  // representation is returned. When the representation gets loaded the
-  // observer's |OnExtensionIconImageLoaded| will be called.
-  gfx::ImageSkiaRep LoadImageForScaleFactor(ui::ScaleFactor scale_factor);
-
-  void OnImageLoaded(float scale_factor, const gfx::Image& image);
-
-  // content::NotificationObserver overrides:
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
-  content::BrowserContext* browser_context_;
-  const Extension* extension_;
-  const ExtensionIconSet& icon_set_;
-  const int resource_size_in_dip_;
-
-  Observer* observer_;
-
-  Source* source_;  // Owned by ImageSkia storage.
-  gfx::ImageSkia image_skia_;
-  // The icon with whose representation |image_skia_| should be updated if
-  // its own representation load fails.
-  gfx::ImageSkia default_icon_;
-
-  content::NotificationRegistrar registrar_;
-
-  base::WeakPtrFactory<IconImage> weak_ptr_factory_;
-
-  DISALLOW_COPY_AND_ASSIGN(IconImage);
-};
-
-}  // namespace extensions
-
-#endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_ICON_IMAGE_H_