rem: var pbi = gPrefService.QueryInterface(Components.interfaces.nsIPrefBranchInternal); pbi.addObserver(this.promptDomain, this, false); 
add: gPrefService.addObserver(this.promptDomain, this, false); 
context: function SanitizeListener(){  var pbi = gPrefService.QueryInterface(Components.interfaces.nsIPrefBranchInternal);  pbi.addObserver(this.promptDomain, this, false);  this._defaultLabel = document.getElementById("sanitizeItem")                               .getAttribute("label");  this._updateSanitizeItem();  if (gPrefService.prefHasUserValue(this.didSanitizeDomain)) {    gPrefService.clearUserPref(this.didSanitizeDomain);    // We need to persist this preference change, since we want to    // check it at next app start even if the browser exits abruptly    gPrefService.savePrefFile(null);  }}
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/9421/b9061c19ada799ee79d1abb677e27d6cad068571/browser.js/clean/browser/base/content/browser.js