Modal组件不显示遮罩，点击空白处仍然可以触发cancel事件

[hzyhbk]

• I have searched the issues of this repository and believe that this is not a duplicate.

Version

1.6.4

Environment

Mac OS 10.15.4 Vue@2.6.11 Antd1.6.4

Reproduction link

Steps to reproduce

1.点击按钮，展示弹框
2. 点击空白处弹框被关闭

What is expected?

点击空白处不触发cancel事件

What is actually happening?

点击空白处触发了cancel事件

[xrkffgg]

maskClosable ?

[hzyhbk]

我的问题点不在于实现点击空白处不关闭弹框，而是组件cancel事件的触发逻辑有问题。设置maskClosable的前提不应该是mask为true吗？当我设置mask为false的时候，mask都不存在了，点击空白处竟然还能触发cancel事件，不是很诡异吗？

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.