Use a direct include of strings headers in url/, win8/.

win8/metro_driver/file_picker_ash.cc

 // Copyright (c) 2013 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 "stdafx.h"
 #include "win8/metro_driver/file_picker_ash.h"
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/win/metro.h"
 #include "base/win/scoped_comptr.h"
 #include "ui/metro_viewer/metro_viewer_messages.h"
 #include "win8/metro_driver/chrome_app_view_ash.h"
 #include "win8/metro_driver/winrt_utils.h"
 
 namespace {
 
 namespace winstorage = ABI::Windows::Storage;
@@ skipping 583 matching lines @@
     } else {
       LOG(ERROR) << "NULL IStorageItem";
     }
   } else {
     LOG(ERROR) << "Unexpected async status " << status;
   }
   app_view_->OnFolderPickerCompleted(this, success_);
   return S_OK;
 }