15863: [Forwardport] Refactored javascript code of admin notification modal popup

Author: IvanPletnyov

app/code/Magento/AdminNotification/view/adminhtml/templates/system/messages/popup.phtml

@@ -23,7 +23,7 @@
     {
         "[data-role=system_messages_list]": {
             "Magento_AdminNotification/js/system/messages/popup": {
-                class: 'modal-system-messages ui-popup-message'
+                "class":"modal-system-messages ui-popup-message"
             }
         }
     }

app/code/Magento/AdminNotification/view/adminhtml/web/js/system/messages/popup.js

@@ -1,24 +1,26 @@
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
-*/
+ */
 
 define([
     'jquery',
     'Magento_Ui/js/modal/modal'
-], function ($) {
+], function ($, modal) {
     'use strict';
 
     return function (data, element) {
-        if (this.modal) {
-            this.modal.html($(element).html());
+
+        if (modal.modal) {
+            modal.modal.html($(element).html());
         } else {
-            this.modal = $(element).modal({
+            modal.modal = $(element).modal({
                 modalClass: data.class,
                 type: 'popup',
                 buttons: []
             });
         }
-        this.modal.modal('openModal');
+
+        modal.modal.modal('openModal');
     };
 });