Add icon-visibility attribute to cr.ui.Tree.

chrome/browser/resources/shared/js/cr/ui/tree.js

 // 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.
 
 cr.define('cr.ui', function() {
   // require cr.ui.define
   // require cr.ui.limitInputWidth
 
   /**
    * The number of pixels to indent per level.
@@ skipping 200 matching lines @@
     getRectForContextMenu: function() {
       // TODO(arv): Add trait support so we can share more code between trees
       // and lists.
       if (this.selectedItem)
         return this.selectedItem.rowElement.getBoundingClientRect();
       return this.getBoundingClientRect();
     }
   };
 
   /**
+   * Determines the visibility of icons next to the treeItem labels. If set to
+   * 'hidden', no space is reserved for icons and no icons are displayed next
+   * to treeItem labels. If set to 'parent', folder icons will be displayed
+   * next to expandable parent nodes. If set to 'all' folder icons will be
+   * displayed next to all nodes. Icons can be set using the treeItem's icon
+   * property.
+   */
+  cr.defineProperty(Tree, 'iconVisibility', cr.PropertyKind.ATTR);
+
+  /**
    * This is used as a blueprint for new tree item elements.
    * @type {!HTMLElement}
    */
   var treeItemProto = (function() {
     var treeItem = cr.doc.createElement('div');
     treeItem.className = 'tree-item';
     treeItem.innerHTML = '<div class=tree-row>' +
         '<span class=expand-icon></span>' +
         '<span class=tree-label></span>' +
         '</div>' +
@@ skipping 425 matching lines @@
     }
     return item;
   }
 
   // Export
   return {
     Tree: Tree,
     TreeItem: TreeItem
   };
 });