Element: [Bug Report] Message.close() doesn't work

[ChuanfengZhang]

Element UI version

2.4.0

OS/Browsers version

Mac OS 10.13.4 (17E199) Chrome 67.0.3396.62

Vue version

2.5.17-beta.0

Reproduction Link

https://jsfiddle.net/prq3vc7g/3/

Steps to reproduce

1.Create a new instance of Message with options: "duration: 0"
2.this.$message.close()

What is Expected?

The current Message can be closed.

What is actually happening?

The current Message can't be closed.
If close() need an id, how can I get it?

[ChuanfengZhang]

According to Doc, there's nothing else need to provide.

[jikkai]

https://jsfiddle.net/prq3vc7g/5/

[ChuanfengZhang]

@jikkai Thanks.