Add a new GetInstance() method for remaining files with singleton classes under chrome/browser.

chrome/browser/download/download_util.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.
 //
 // Download utility implementation
 
 #include "chrome/browser/download/download_util.h"
 
 #if defined(OS_WIN)
 #include <shobjidl.h>
 #endif
 #include <string>
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/file_util.h"
 #include "base/i18n/rtl.h"
 #include "base/i18n/time_formatting.h"
+#include "base/lazy_instance.h"
 #include "base/path_service.h"
-#include "base/singleton.h"
 #include "base/string16.h"
 #include "base/string_number_conversions.h"
 #include "base/stringprintf.h"
 #include "base/sys_string_conversions.h"
 #include "base/thread_restrictions.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "base/win/windows_version.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/download/download_extensions.h"
@@ skipping 70 matching lines @@
   DefaultDownloadDirectory() {
     if (!PathService::Get(chrome::DIR_DEFAULT_DOWNLOADS, &path_)) {
       NOTREACHED();
     }
     if (DownloadPathIsDangerous(path_)) {
       if (!PathService::Get(chrome::DIR_DEFAULT_DOWNLOADS_SAFE, &path_)) {
         NOTREACHED();
       }
     }
   }
-  friend struct DefaultSingletonTraits<DefaultDownloadDirectory>;
+  friend struct base::DefaultLazyInstanceTraits<DefaultDownloadDirectory>;
   FilePath path_;
 };
 
+static base::LazyInstance<DefaultDownloadDirectory>
+    g_default_download_directory(base::LINKER_INITIALIZED);
+
 const FilePath& GetDefaultDownloadDirectory() {
-  return Singleton<DefaultDownloadDirectory>::get()->path();
+  return g_default_download_directory.Get().path();
 }
 
 bool CreateTemporaryFileForDownload(FilePath* temp_file) {
   if (file_util::CreateTemporaryFileInDir(GetDefaultDownloadDirectory(),
                                           temp_file))
     return true;
   return file_util::CreateTemporaryFile(temp_file);
 }
 
 bool DownloadPathIsDangerous(const FilePath& download_path) {
@@ skipping 606 matching lines @@
         !service->IsDownloadFromGallery(info->url, info->referrer_url)) {
       // Extensions that are not from the gallery are considered dangerous.
       return true;
     }
   }
 
   return false;
 }
 
 }  // namespace download_util