Checking node object before checking its property.

chrome/browser/resources/bookmark_manager/js/main.js

 // 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.
 
 'use strict';
 
 (function() {
 /** @const */ var BookmarkList = bmm.BookmarkList;
 /** @const */ var BookmarkTree = bmm.BookmarkTree;
 /** @const */ var Command = cr.ui.Command;
@@ skipping 299 matching lines @@
 /**
  * Returns a promise for all the URLs in the {@code nodes} and the direct
  * children of {@code nodes}.
  * @param {!Array<BookmarkTreeNode>} nodes .
  * @return {!Promise<Array<string>>} .
  */
 function getAllUrls(nodes) {
   var urls = [];
 
   // Adds the node and all its direct children.
+  // TODO(deepak.m1): Here node should exist. When we delete the nodes then
+  // datamodel gets updated but still it shows deleted items as selected items
+  // and accessing those nodes throws chrome.runtime.lastError. This cause
+  // undefined value for node. Please refer https://crbug.com/480935.
   function addNodes(node) {
-    if (node.id == 'new')
+    if (!node || node.id == 'new')
       return;
 
     if (node.children) {
       node.children.forEach(function(child) {
         if (!bmm.isFolder(child))
           urls.push(child.url);
       });
     } else {
       urls.push(node.url);
     }
@@ skipping 1185 matching lines @@
 
   cr.ui.FocusOutlineManager.forDocument(document);
   initializeSplitter();
   bmm.addBookmarkModelListeners();
   dnd.init(selectItemsAfterUserAction);
   bmm.tree.reload();
 }
 
 initializeBookmarkManager();
 })();