Those messages already appear on Chrome and Firefox.
I believe (in Chrome, at least) that currently, that’s only for forms with password or CC fields. Non-HTTPS sites with just generic fields don’t display “Not secure” in the address bar - at least for me.
Oh, I see. All text inputs now.
The article explains how this is changing in new versions of Chrome. I believe the Chrome team have a target to move away from telling people a site is “secure” and instead notify them for any site that is not secured with TLS. This is just one more step along that road.