No need to pass DownloadItemModel ownership.

chrome/browser/ui/gtk/download/download_shelf_gtk.cc

 // 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.
 
 #include "chrome/browser/ui/gtk/download/download_shelf_gtk.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "chrome/browser/download/download_item_model.h"
@@ skipping 161 matching lines @@
   items_hbox_.Destroy();
 
   // Make sure we're no longer an observer of the message loop.
   SetCloseOnMouseOut(false);
 }
 
 content::PageNavigator* DownloadShelfGtk::GetNavigator() {
   return browser_;
 }
 
-void DownloadShelfGtk::DoAddDownload(DownloadItemModel* download_model) {
-  download_items_.push_back(new DownloadItemGtk(this, download_model));
+void DownloadShelfGtk::DoAddDownload(DownloadItem* download) {
+  download_items_.push_back(new DownloadItemGtk(this, download));
 }
 
 bool DownloadShelfGtk::IsShowing() const {
   return slide_widget_->IsShowing();
 }
 
 bool DownloadShelfGtk::IsClosing() const {
   return slide_widget_->IsClosing();
 }
 
 void DownloadShelfGtk::DoShow() {
   slide_widget_->Open();
   browser_->UpdateDownloadShelfVisibility(true);
   CancelAutoClose();
 }
 
 void DownloadShelfGtk::DoClose() {
   // When we are closing, we can vertically overlap the render view. Make sure
   // we are on top.
   gdk_window_raise(gtk_widget_get_window(shelf_.get()));
   slide_widget_->Close();
   browser_->UpdateDownloadShelfVisibility(false);
   int num_in_progress = 0;
   for (size_t i = 0; i < download_items_.size(); ++i) {
-    if (download_items_[i]->get_download()->IsInProgress())
+    if (download_items_[i]->download()->IsInProgress())
       ++num_in_progress;
   }
   download_util::RecordShelfClose(
       download_items_.size(), num_in_progress, close_on_mouse_out_);
   SetCloseOnMouseOut(false);
 }
 
 Browser* DownloadShelfGtk::browser() const {
   return browser_;
 }
 
 void DownloadShelfGtk::Closed() {
   // Don't remove completed downloads if the shelf is just being auto-hidden
   // rather than explicitly closed by the user.
   if (is_hidden())
     return;
   // When the close animation is complete, remove all completed downloads.
   size_t i = 0;
   while (i < download_items_.size()) {
-    DownloadItem* download = download_items_[i]->get_download();
+    DownloadItem* download = download_items_[i]->download();
     bool is_transfer_done = download->IsComplete() ||
                             download->IsCancelled() ||
                             download->IsInterrupted();
     if (is_transfer_done &&
         download->GetSafetyState() != DownloadItem::DANGEROUS) {
       RemoveDownloadItem(download_items_[i]);
     } else {
       // We set all remaining items as "opened", so that the shelf will auto-
       // close in the future without the user clicking on them.
       download->SetOpened(true);
@@ skipping 70 matching lines @@
     Close();
   } else {
     // The link button was clicked.
     chrome::ShowDownloads(browser_);
   }
 }
 
 void DownloadShelfGtk::AutoCloseIfPossible() {
   for (std::vector<DownloadItemGtk*>::iterator iter = download_items_.begin();
        iter != download_items_.end(); ++iter) {
-    if (!(*iter)->get_download()->GetOpened())
+    if (!(*iter)->download()->GetOpened())
       return;
   }
 
   SetCloseOnMouseOut(true);
 }
 
 void DownloadShelfGtk::CancelAutoClose() {
   SetCloseOnMouseOut(false);
   weak_factory_.InvalidateWeakPtrs();
 }
@@ skipping 66 matching lines @@
 
   MessageLoop::current()->PostDelayedTask(
       FROM_HERE,
       base::Bind(&DownloadShelfGtk::Close, weak_factory_.GetWeakPtr()),
       base::TimeDelta::FromMilliseconds(kAutoCloseDelayMs));
 }
 
 void DownloadShelfGtk::MouseEnteredShelf() {
   weak_factory_.InvalidateWeakPtrs();
 }