No need to pass DownloadItemModel ownership.

chrome/browser/ui/views/download/download_item_view.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.
 //
 // A ChromeView that implements one download on the Download shelf.
 // Each DownloadItemView contains an application icon, a text label
 // indicating the download's file name, a text label indicating the
 // download's status (such as the number of bytes downloaded so far)
 // and a button for canceling an in progress download, or opening
 // the completed download.
 //
 // The DownloadItemView lives in the Browser, and has a corresponding
 // DownloadController that receives / writes data which lives in the
 // Renderer.
 
 #ifndef CHROME_BROWSER_UI_VIEWS_DOWNLOAD_DOWNLOAD_ITEM_VIEW_H__
 #define CHROME_BROWSER_UI_VIEWS_DOWNLOAD_DOWNLOAD_ITEM_VIEW_H__
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/string_util.h"
 #include "base/time.h"
 #include "base/timer.h"
 #include "chrome/browser/common/cancelable_request.h"
+#include "chrome/browser/download/download_item_model.h"
 #include "chrome/browser/icon_manager.h"
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/download_manager.h"
 #include "ui/base/animation/animation_delegate.h"
 #include "ui/gfx/font.h"
 #include "ui/views/context_menu_controller.h"
 #include "ui/views/controls/button/button.h"
 #include "ui/views/view.h"
 
-class DownloadItemModel;
 class DownloadShelfView;
 class DownloadShelfContextMenuView;
 
 namespace gfx {
 class Image;
 class ImageSkia;
 }
 
 namespace ui {
 class SlideAnimation;
 }
 
 namespace views {
 class Label;
 class TextButton;
 }
 
 class DownloadItemView : public views::ButtonListener,
                          public views::View,
                          public views::ContextMenuController,
                          public content::DownloadItem::Observer,
                          public ui::AnimationDelegate {
  public:
   DownloadItemView(content::DownloadItem* download,
-                   DownloadShelfView* parent,
-                   DownloadItemModel* model);
+                   DownloadShelfView* parent);
   virtual ~DownloadItemView();
 
   // Timer callback for handling animations
   void UpdateDownloadProgress();
   void StartDownloadProgress();
   void StopDownloadProgress();
 
   // IconManager::Client interface.
   void OnExtractIconComplete(gfx::Image* icon);
 
   // Returns the DownloadItem model object belonging to this item.
-  content::DownloadItem* download() const { return download_; }
+  content::DownloadItem* download() { return model_.download(); }
 
   // DownloadItem::Observer methods
   virtual void OnDownloadUpdated(content::DownloadItem* download) OVERRIDE;
   virtual void OnDownloadOpened(content::DownloadItem* download) OVERRIDE;
   virtual void OnDownloadDestroyed(content::DownloadItem* download) OVERRIDE;
 
   // Overridden from views::View:
   virtual void Layout() OVERRIDE;
   virtual gfx::Size GetPreferredSize() OVERRIDE;
   virtual bool OnMousePressed(const ui::MouseEvent& event) OVERRIDE;
@@ skipping 140 matching lines @@
   BodyImageSet pushed_body_image_set_;
   BodyImageSet dangerous_mode_body_image_set_;
   BodyImageSet malicious_mode_body_image_set_;
   DropDownImageSet normal_drop_down_image_set_;
   DropDownImageSet hot_drop_down_image_set_;
   DropDownImageSet pushed_drop_down_image_set_;
 
   // The warning icon showns for dangerous downloads.
   const gfx::ImageSkia* warning_icon_;
 
-  // The model we query for display information
-  content::DownloadItem* download_;
-
   // The download shelf that owns us.
   DownloadShelfView* shelf_;
 
   // Elements of our particular download
   string16 status_text_;
 
   // The font used to print the file name and status.
   gfx::Font font_;
 
   // The tooltip.  Only displayed when not showing a warning dialog.
@@ skipping 27 matching lines @@
 
   // Whether we are tracking a possible drag.
   bool starting_drag_;
 
   // Position that a possible drag started at.
   gfx::Point drag_start_point_;
 
   // For canceling an in progress icon request.
   CancelableTaskTracker cancelable_task_tracker_;
 
-  // A model class to control the status text we display and the cancel
-  // behavior.
-  // This class owns the pointer.
-  scoped_ptr<DownloadItemModel> model_;
+  // A model class to control the status text we display.
+  DownloadItemModel model_;
 
   // Hover animations for our body and drop buttons.
   scoped_ptr<ui::SlideAnimation> body_hover_animation_;
   scoped_ptr<ui::SlideAnimation> drop_hover_animation_;
 
   // Animation for download complete.
   scoped_ptr<ui::SlideAnimation> complete_animation_;
 
   // Progress animation
   base::RepeatingTimer<DownloadItemView> progress_timer_;
@@ skipping 29 matching lines @@
 
   // The icon loaded in the download shelf is based on the file path of the
   // item.  Store the path used, so that we can detect a change in the path
   // and reload the icon.
   FilePath last_download_item_path_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadItemView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_DOWNLOAD_DOWNLOAD_ITEM_VIEW_H__