add: UpdateTreeGrouping(); 
context:   observe: function(aPrefBranch, aTopic, aPrefName) {    try {      GroupBy(aPrefBranch.QueryInterface(Components.interfaces.nsIPrefBranch).getCharPref(aPrefName));    }    catch(ex) {    }  }
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/10234/6217b4e655605e272563811dd65f5d17684d5ec6/history.js/clean/xpfe/components/history/resources/history.js