add: return null; 
context:   QueryInterface : function(iid)  {    if(iid.equals(Components.interfaces.nsIXULBrowserWindow))      return this;    throw Components.results.NS_NOINTERFACE;  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/a3fd1360f8a3ed6857cc435f9c9b5e8b3cdd9ef2/navigator.js/clean/xpfe/browser/resources/content/navigator.js