'click' Trigger doesn't hide pop up when user clicks on an iframe in the page

Behaviour:
When using rc-trigger (eg. via Ant Design's Dropdown) with a click type of trigger, the popup will not be closed if a user clicks or taps on an iframe in the page.

Expected Behaviour:
When a user clicks or taps anywhere on the document or an iframe within the document, the popup will be closed. This works fine for contextMenu types of triggers.

Steps to Reproduce:
(Using Ant Design Dropdown)

• Render a view that contains a Dropdown (with trigger={['click']}) and an iframe that takes up a large part of the screen
• Open the Dropdown overlay (popup) by clicking on the Dropdown
• Click on the iFrame
• Outcome: the Dropdown popup will not close

I have submitted a PR to help with fixing this https://github.com/react-component/trigger/pull/96

Überprüfe zuerst pull request #96 und reproduziere dann das Problem mit einem Ant Design Dropdown mit trigger={['click']} und einem iframe, das einen großen Teil der Seite einnimmt. Stelle sicher, dass das Klicken oder Tippen auf das iframe das Popup schließt, entsprechend dem bestehenden contextMenu-Verhalten.