Remove use of deprecated MessageLoop methods in chrome/.

chrome/browser/printing/background_printing_manager.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/printing/background_printing_manager.h"
 
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
 #include "base/stl_util.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/printing/print_job.h"
 #include "chrome/browser/printing/print_preview_dialog_controller.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_source.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
@@ skipping 89 matching lines @@
 
   // Stop all observation ...
   registrar_.Remove(this, chrome::NOTIFICATION_PRINT_JOB_RELEASED,
                     content::Source<WebContents>(preview_contents));
   Observer* observer = i->second;
   printing_contents_map_.erase(i);
   delete observer;
 
   // ... and mortally wound the contents. (Deletion immediately is not a good
   // idea in case this was called from RenderViewGone.)
-  base::MessageLoop::current()->DeleteSoon(FROM_HERE, preview_contents);
+  base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, preview_contents);
 }
 
 std::set<content::WebContents*> BackgroundPrintingManager::CurrentContentSet() {
   std::set<content::WebContents*> result;
   for (WebContentsObserverMap::iterator i = printing_contents_map_.begin();
        i != printing_contents_map_.end(); ++i) {
     result.insert(i->first);
   }
   return result;
 }
 
 bool BackgroundPrintingManager::HasPrintPreviewDialog(
     WebContents* preview_dialog) {
   return ContainsKey(printing_contents_map_, preview_dialog);
 }
 
 }  // namespace printing