Fix the issue introduced by hooking window.onbeforeunload in WebDialogView which breaks WebDialogUI…

ui/web_dialogs/web_dialog_ui.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 "ui/web_dialogs/web_dialog_ui.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/lazy_instance.h"
 #include "base/values.h"
@@ skipping 92 matching lines @@
     delegate->OnDialogShown(web_ui(), render_view_host);
 }
 
 void WebDialogUI::OnDialogClosed(const ListValue* args) {
   WebDialogDelegate* delegate = GetDelegate(web_ui()->GetWebContents());
   if (delegate) {
     std::string json_retval;
     if (args && !args->empty() && !args->GetString(0, &json_retval))
       NOTREACHED() << "Could not read JSON argument";
 
-    delegate->OnDialogClosed(json_retval);
+    delegate->OnDialogCloseFromWebUI(json_retval);
   }
 }
 
 ExternalWebDialogUI::ExternalWebDialogUI(content::WebUI* web_ui)
     : WebDialogUI(web_ui) {
   // Non-file based UI needs to not have access to the Web UI bindings
   // for security reasons. The code hosting the dialog should provide
   // dialog specific functionality through other bindings and methods
   // that are scoped in duration to the dialogs existence.
   web_ui->SetBindings(web_ui->GetBindings() & ~content::BINDINGS_POLICY_WEB_UI);
 }
 
 ExternalWebDialogUI::~ExternalWebDialogUI() {
 }
 
 }  // namespace ui