[Bug Report] Why cant my '$confirm' set option 'distinguishCancelAndClose'?There is also no ts declare for it in my package.

[ludesong]

Element UI version

2.4.4

OS/Browsers version

win10

Vue version

2.5.17-beta.0

Reproduction Link

#11831

Steps to reproduce

just install it and use $confirm

What is Expected?

can use option 'distinguishCancelAndClose'

What is actually happening?

cant

[HungryBird]

why it dosent work when I copy demo's code on http://element-cn.eleme.io/#/zh-CN/component/message-box.
I missing what type?