add: if (gCancelCallback) gCancelCallback(); 
context: function onCancel(){  // close the window  return true;}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/8897f7c963a281b883377911e566db8670cbb17f/mailViewList.js/buggy/mailnews/extensions/mailviews/resources/content/mailViewList.js