question about on reportchange

hi :
when i used on('reportchange'), i found that, if we gave a option in the report  in the beginning , 
flexmonster consider as there is a change !
 
for example : in the page   http://jsfiddle.net/flexmonster/w3a7hxs9/, try give un option in the report 

var pivot = new Flexmonster({
 container: "pivot-container",
 componentFolder: "https://cdn.flexmonster.com/",
 toolbar: true,
 report: {
     dataSource: {
         data: getData()
     },
     options: {
         "viewType": "charts"
     } 
 }
});

thank you !