return IO.newURI(IO.newURI(aBase).resolve(aUrl)).spec; 
 return IO.newURI(aUrl, null, IO.newURI(aBase)).spec; 
function makeURLAbsolute(aBase, aUrl){  return IO.newURI(IO.newURI(aBase).resolve(aUrl)).spec;}
5872	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/5872/0a231b821d8f052cd00e1e97acd16f52e60a3a53/utilityOverlay.js/clean/browser/base/content/utilityOverlay.js