rem: this.update.QueryInterface(Components.interfaces.nsIWritablePropertyBag); 
add: if (this.update) this.update.QueryInterface(Components.interfaces.nsIWritablePropertyBag); 
context:   setUpdate: function(update) {    this.update = update;    this.update.QueryInterface(Components.interfaces.nsIWritablePropertyBag);  },
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/1913ec82260761054c2d63fff96914c4954a71c3/updates.js/clean/toolkit/mozapps/update/content/updates.js