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diff --git a/extensions/browser/image_loader.h b/extensions/browser/image_loader.h
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+// 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"
+#include "base/gtest_prod_util.h"
+#include "base/memory/weak_ptr.h"
+#include "components/keyed_service/core/keyed_service.h"
+#include "extensions/common/extension_resource.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/base/layout.h"
+#include "ui/gfx/size.h"
+
+namespace content {
+class BrowserContext;
+}
+
+namespace gfx {
+class Image;
+class ImageFamily;
+}
+
+namespace extensions {
+
+class Extension;
+
+typedef base::Callback<void(const gfx::Image&)> ImageLoaderImageCallback;
+typedef base::Callback<void(const gfx::ImageFamily&)>
+    ImageLoaderImageFamilyCallback;
+
+// This class is responsible for asynchronously loading extension images and
+// calling a callback when an image is loaded.
+// The views need to load their icons asynchronously might be deleted before
+// the images have loaded. If you pass your callback using a weak_ptr, this
+// will make sure the callback won't be called after the view is deleted.
+class ImageLoader : public KeyedService {
+ public:
+  // Information about a singe image representation to load from an extension
+  // resource.
+  struct ImageRepresentation {
+    // Enum values to indicate whether to resize loaded bitmap when it is larger
+    // than |desired_size| or always resize it.
+    enum ResizeCondition { RESIZE_WHEN_LARGER, ALWAYS_RESIZE, NEVER_RESIZE };
+
+    ImageRepresentation(const ExtensionResource& resource,
+                        ResizeCondition resize_condition,
+                        const gfx::Size& desired_size,
+                        ui::ScaleFactor scale_factor);
+    ~ImageRepresentation();
+
+    // Extension resource to load.
+    ExtensionResource resource;
+
+    ResizeCondition resize_condition;
+
+    // When |resize_method| is ALWAYS_RESIZE or when the loaded image is larger
+    // than |desired_size| it will be resized to these dimensions.
+    gfx::Size desired_size;
+
+    // |scale_factor| is used to construct the loaded gfx::ImageSkia.
+    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();
+
+  // 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,
+                      const ImageLoaderImageCallback& callback);
+
+  // Same as LoadImageAsync() above except it loads multiple images from the
+  // same extension. This is used to load multiple resolutions of the same image
+  // type.
+  void LoadImagesAsync(const extensions::Extension* extension,
+                       const std::vector<ImageRepresentation>& info_list,
+                       const ImageLoaderImageCallback& callback);
+
+  // Same as LoadImagesAsync() above except it loads into an image family. This
+  // is used to load multiple images of different logical sizes as opposed to
+  // LoadImagesAsync() which loads different scale factors of the same logical
+  // image size.
+  //
+  // If multiple images of the same logical size are loaded, they will be
+  // combined into a single ImageSkia in the ImageFamily.
+  void LoadImageFamilyAsync(const extensions::Extension* extension,
+                            const std::vector<ImageRepresentation>& info_list,
+                            const ImageLoaderImageFamilyCallback& callback);
+
+ private:
+  void ReplyBack(const ImageLoaderImageCallback& callback,
+                 const std::vector<LoadResult>& load_result);
+
+  void ReplyBackWithImageFamily(const ImageLoaderImageFamilyCallback& callback,
+                                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_