Version: 56.0.2912.0
OS: Mac

What steps will reproduce the problem?
(1) Visit http://example.com
(2) Run the following Javascript in the devtools console:
var i = document.createElement("iframe")
i.src="http://http-password.badssl.com"
document.body.appendChild(i)
(3) Observe the "Not secure" warning in the omnibox.
(4) Run the following javascript:
i.style="display:none;"

What is the expected output?
The "Not secure" omnibox warning goes away.

What do you see instead?
The "Not secure" warning stays in the omnibox.

Layout objects must not get destroyed when an iframe is hidden.

This is probably what's happening on times.com as well.