Add a new GetInstance() method for singleton classes used in chrome/browser files.

chrome/browser/dom_ui/print_preview_ui.cc

 // Copyright (c) 2010 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/dom_ui/print_preview_ui.h"
 
 #include <algorithm>
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
@@ skipping 122 matching lines @@
 
 PrintPreviewUI::PrintPreviewUI(TabContents* contents) : DOMUI(contents) {
   // PrintPreviewUI owns |handler|.
   PrintPreviewHandler* handler = new PrintPreviewHandler();
   AddMessageHandler(handler->Attach(this));
 
   // Set up the chrome://print/ source.
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       NewRunnableMethod(
-          Singleton<ChromeURLDataManager>::get(),
+          ChromeURLDataManager::GetInstance(),
           &ChromeURLDataManager::AddDataSource,
           make_scoped_refptr(new PrintPreviewUIHTMLSource())));
 }
 
 PrintPreviewUI::~PrintPreviewUI() {
 }