Add interface to CancelableRequest that allows use of base::Callback<>.

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

 // Copyright (c) 2011 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_item_gtk.h"
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/metrics/histogram.h"
 #include "base/string_util.h"
@@ skipping 443 matching lines @@
   icon_large_ = image;
   DownloadItemDrag::SetSource(body_.get(), get_download(), icon_large_);
 }
 
 void DownloadItemGtk::LoadIcon() {
   icon_consumer_.CancelAllRequests();
   IconManager* im = g_browser_process->icon_manager();
   icon_filepath_ = get_download()->GetUserVerifiedFilePath();
   im->LoadIcon(icon_filepath_,
                IconLoader::SMALL, &icon_consumer_,
-               NewCallback(this, &DownloadItemGtk::OnLoadSmallIconComplete));
+               base::Bind(&DownloadItemGtk::OnLoadSmallIconComplete,
+                          base::Unretained(this)));
   im->LoadIcon(icon_filepath_,
                IconLoader::LARGE, &icon_consumer_,
-               NewCallback(this, &DownloadItemGtk::OnLoadLargeIconComplete));
+               base::Bind(&DownloadItemGtk::OnLoadLargeIconComplete,
+                          base::Unretained(this)));
 }
 
 void DownloadItemGtk::UpdateTooltip() {
   string16 elided_filename = ui::ElideFilename(
       get_download()->GetFileNameToReportUser(),
       gfx::Font(), kTooltipMaxWidth);
   gtk_widget_set_tooltip_text(body_.get(),
                               UTF16ToUTF8(elided_filename).c_str());
 }
 
@@ skipping 404 matching lines @@
   get_download()->DangerousDownloadValidated();
 }
 
 void DownloadItemGtk::OnDangerousDecline(GtkWidget* button) {
   UMA_HISTOGRAM_LONG_TIMES("clickjacking.discard_download",
                            base::Time::Now() - creation_time_);
   if (get_download()->IsPartialDownload())
     get_download()->Cancel(true);
   get_download()->Delete(DownloadItem::DELETE_DUE_TO_USER_DISCARD);
 }