It makes more sense to use the plugin. but if you want to do it via "Browser.ExecJS" you can write this.
Browser.ExecJS("function date()
{
var months = ['January','February','March','April','May','June','July','August','September','October','November','December'];
var now = new Date();
var thisMonth = months[now.getMonth()];
var day = now.getDay();
var year = now.getFullYear();
var text = day+' '+thisMonth+' '+year;
return text;
}
date()")