Really fix crash when dragging and dropping in chrome://settings/startup

chrome/browser/resources/options/startup_overlay.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.
 
 cr.define('options', function() {
   /** @const */ var ArrayDataModel = cr.ui.ArrayDataModel;
   /** @const */ var OptionsPage = options.OptionsPage;
   /** @const */ var SettingsDialog = options.SettingsDialog;
 
   /**
@@ skipping 107 matching lines @@
     },
 
     /**
      * Updates the startup pages list with the given entries.
      * @param {Array} pages List of startup pages.
      * @private
      */
     updateStartupPages_: function(pages) {
       var model = new ArrayDataModel(pages);
       // Add a "new page" row.
-      model.push({
-        'modelIndex': '-1'
-      });
+      model.push({modelIndex: -1});
       $('startupPagesList').dataModel = model;
     },
 
     /**
      * Sends an asynchronous request for new autocompletion suggestions for the
      * the given query. When new suggestions are available, the C++ handler will
      * call updateAutocompleteSuggestions_.
      * @param {string} query List of autocomplete suggestions.
      * @private
      */
@@ skipping 27 matching lines @@
       var instance = StartupOverlay.getInstance();
       return instance[name + '_'].apply(instance, arguments);
     };
   });
 
   // Export
   return {
     StartupOverlay: StartupOverlay
   };
 });