Password protected pages require the password only once

[ctienshi]

after entering the password for a password protected page it does not ask for the password again to see the page after logging out of wordpress and logging in again. This could be a security vulnerability and a bug because the password for Wordpress and the password for the Password protected page are different.

[SergeyBiryukov]

Related: #16483, #21466, #21517.

[iandunn]

Switching from wontfix to maybelater, since that's more accurate.

xref: ​https://make.wordpress.org/core/2019/01/14/follow-up-on-recent-trac-bulk-edit/

[johnbillion]

Duplicate of #16483.