解决event.layerX and event.layerY are broken and deprecated in WebKit的问题

在chrome控制台下显示错误：

event.layerX and event.layerY are broken and deprecated in WebKit. They will be removed from the engine in the near future.

这是JQuery的一个Bug，添加以下代码就能解决，在最新的jQuery中（1.7.1以后）已经不存在这个问题，

(function(){
    // remove layerX and layerY
    var all = $.event.props,
        len = all.length,
        res = [];
    while (len--) {
      var el = all[len];
      if (el != 'layerX' && el != 'layerY') res.push(el);
    }
    $.event.props = res;
}());

还可以看看http://jsperf.com/removing-event-props/9