DevTools: DataGrid: turn "element" getter to function.

Source/devtools/front_end/components/CookiesTable.js

 /*
  * Copyright (C) 2009 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 129 matching lines @@
         var selectedCookie = this._nextSelectedCookie || this.selectedCookie();
         this._nextSelectedCookie = null;
         this._dataGrid.rootNode().removeChildren();
         for (var i = 0; i < this._data.length; ++i) {
             var item = this._data[i];
             if (item.folderName) {
                 var groupData = {name: item.folderName, value: "", domain: "", path: "", expires: "", size: this._totalSize(item.cookies), httpOnly: "", secure: ""};
                 var groupNode = new WebInspector.DataGridNode(groupData);
                 groupNode.selectable = true;
                 this._dataGrid.rootNode().appendChild(groupNode);
-                groupNode.element.classList.add("row-group");
+                groupNode.element().classList.add("row-group");
                 this._populateNode(groupNode, item.cookies, selectedCookie);
                 groupNode.expand();
             } else
                 this._populateNode(this._dataGrid.rootNode(), item.cookies, selectedCookie);
         }
     },
 
     /**
      * @param {!WebInspector.DataGridNode} parentNode
      * @param {?Array.<!WebInspector.Cookie>} cookies
@@ skipping 116 matching lines @@
     },
 
     _refresh: function()
     {
         if (this._refreshCallback)
             this._refreshCallback();
     },
 
     __proto__: WebInspector.VBox.prototype
 }