Convert IconManager to use new CancelableTaskTracker

chrome/browser/ui/cocoa/download/download_item_mac.mm

 // 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/cocoa/download/download_item_mac.h"
 
 #include "base/callback.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/download/download_item_model.h"
 #import "chrome/browser/ui/cocoa/download/download_item_controller.h"
 #include "content/public/browser/download_item.h"
 #include "ui/gfx/image/image.h"
 
 using content::DownloadItem;
 
 // DownloadItemMac -------------------------------------------------------------
 
 DownloadItemMac::DownloadItemMac(DownloadItemModel* download_model,
                                  DownloadItemController* controller)
     : download_model_(download_model), item_controller_(controller) {
   download_model_->download()->AddObserver(this);
 }
 
 DownloadItemMac::~DownloadItemMac() {
   download_model_->download()->RemoveObserver(this);
-  icon_consumer_.CancelAllRequests();
 }
 
 void DownloadItemMac::OnDownloadUpdated(content::DownloadItem* download) {
   DCHECK_EQ(download, download_model_->download());
 
   if ([item_controller_ isDangerousMode] && !download_model_->IsDangerous()) {
     // We have been approved.
     [item_controller_ clearDangerousMode];
   }
 
@@ skipping 45 matching lines @@
 
   // We may already have this particular image cached.
   FilePath file = download_model_->download()->GetUserVerifiedFilePath();
   gfx::Image* icon = icon_manager->LookupIcon(file, IconLoader::ALL);
   if (icon) {
     [item_controller_ setIcon:icon->ToNSImage()];
     return;
   }
 
   // The icon isn't cached, load it asynchronously.
-  icon_manager->LoadIcon(file, IconLoader::ALL, &icon_consumer_,
+  icon_manager->LoadIcon(file,
+                         IconLoader::ALL,
                          base::Bind(&DownloadItemMac::OnExtractIconComplete,
-                                    base::Unretained(this)));
+                                    base::Unretained(this)),
+                         &cancelable_task_tracker_);
 }
 
-void DownloadItemMac::OnExtractIconComplete(IconManager::Handle handle,
-                                            gfx::Image* icon) {
+void DownloadItemMac::OnExtractIconComplete(gfx::Image* icon) {
   if (!icon)
     return;
   [item_controller_ setIcon:icon->ToNSImage()];
 }