rem: function onUnload() 
add: function onUnload() 
context: function onUnload() {  if (printProgress)  {   try    {     printProgress.unregisterListener(progressListener);     printProgress = null;   }       catch( exception ) {}  }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/59cd8cec6e8a8a946512ae4ad7ee8b2f545283fd/printProgress.js/buggy/xpfe/global/resources/content/printProgress.js