[cros,de-hack] Get rid of singleton for the WebUILoginScreen.

chrome/browser/ui/webui/chromeos/login/network_dropdown_handler.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/webui/chromeos/login/network_dropdown_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "chrome/browser/chromeos/login/webui_login_display.h"
 #include "chrome/browser/ui/webui/chromeos/login/network_dropdown.h"
@@ skipping 53 matching lines @@
   dropdown_->OnItemChosen(static_cast<int>(id));
 }
 
 void NetworkDropdownHandler::HandleNetworkDropdownShow(
     const base::ListValue* args) {
   DCHECK(args->GetSize() == 1);
   std::string element_id;
   if (!args->GetString(0, &element_id))
     NOTREACHED();
 
-  dropdown_.reset(new NetworkDropdown(
-      web_ui_, WebUILoginDisplay::GetLoginWindow()->GetNativeWindow()));
+  dropdown_.reset(new NetworkDropdown(web_ui_, GetNativeWindow()));
 }
 
 void NetworkDropdownHandler::HandleNetworkDropdownHide(
     const base::ListValue* args) {
   DCHECK(args->GetSize() == 0);
   dropdown_.reset();
 }
 
 void NetworkDropdownHandler::HandleNetworkDropdownRefresh(
     const base::ListValue* args) {
   DCHECK(args->GetSize() == 0);
   // Since language change is async,
   // we may in theory be on another screen during this call.
   if (dropdown_.get())
     dropdown_->Refresh();
 }
 
 }  // namespace chromeos