static/ext/src/util/Sorter.js
function(fn) {
        var me = this;
        fn = fn || me.sorterFn || me.defaultSorterFn;
        me.sort = me.createSortFunction(fn);
    }
function(fn) {
        var me = this;
        fn = fn || me.sorterFn || me.defaultSorterFn;
        me.sort = me.createSortFunction(fn);
    }
Update the sort function for this sorter.
@param {Function} [fn] A new sorter function for this sorter. If not specified it will use the default
sorting function.