DevTools: migrate treeoutline from hasChildren to is/setExpandable().

Source/devtools/front_end/resources/ResourcesPanel.js

 /*
  * Copyright (C) 2007, 2008, 2010 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Joseph Pecoraro
  * Copyright (C) 2013 Samsung Electronics. 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 816 matching lines @@
         return Promise.resolve();
     }
 }
 
 /**
  * @constructor
  * @extends {TreeElement}
  * @param {!WebInspector.ResourcesPanel} storagePanel
  * @param {string} title
  * @param {?Array.<string>=} iconClasses
- * @param {boolean=} hasChildren
+ * @param {boolean=} expandable
  * @param {boolean=} noIcon
  */
-WebInspector.BaseStorageTreeElement = function(storagePanel, title, iconClasses, hasChildren, noIcon)
+WebInspector.BaseStorageTreeElement = function(storagePanel, title, iconClasses, expandable, noIcon)
 {
-    TreeElement.call(this, "", hasChildren);
+    TreeElement.call(this, "", expandable);
     this._storagePanel = storagePanel;
     this._titleText = title;
     this._iconClasses = iconClasses;
     this._noIcon = noIcon;
 }
 
 WebInspector.BaseStorageTreeElement.prototype = {
     onattach: function()
     {
         this.listItemElement.removeChildren();
@@ skipping 1124 matching lines @@
             if (!indexNames[indexName])
                 this._indexRemoved(indexName);
         }
         for (var indexName in this._idbIndexTreeElements) {
             if (!indexNames[indexName]) {
                 this.removeChild(this._idbIndexTreeElements[indexName]);
                 delete this._idbIndexTreeElements[indexName];
             }
         }
 
-        if (this.childCount()) {
-            this.hasChildren = true;
+        if (this.childCount())
             this.expand();
-        }
 
         if (this._view)
             this._view.update(this._objectStore);
 
         this._updateTooltip();
     },
 
     _updateTooltip: function()
     {
 
@@ skipping 395 matching lines @@
 WebInspector.ResourcesPanelFactory.prototype = {
     /**
      * @override
      * @return {!WebInspector.Panel}
      */
     createPanel: function()
     {
         return WebInspector.ResourcesPanel._instance();
     }
 }