在chrome下测试不行...不过这个代码的原理到底是啥...
TypeError: Array.prototype.sort called on null or undefined
arguments: Array[1]
get message: function getter() { [native code] }
get stack: function getter() { [native code] }
set message: function setter() { [native code] }
set stack: function setter() { [native code] }
type: "called_on_null_or_undefined"
__proto__: Error