[Partitioned Popins] Opener and popin both must be https
We require that the opener of the popin and the popin itself always be
https. A later CL will ensure that the popin cannot navigate/redirect
anywhere insecure, but for now this is just some initial gating in the
renderer and browser process.
Explainer: https://explainers-by-googlers.github.io/partitioned-popins/
I2P: https://groups.google.com/a/chromium.org/g/blink-dev/c/ApU_zUmpQ2g/
Bug: 340606651
Change-Id: I1611fb34e008a6eaa0dedea1f19e8591fb90053a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5817535
Auto-Submit: Ari Chivukula arichiv@chromium.org
Reviewed-by: Philip Rogers pdr@chromium.org
Commit-Queue: Philip Rogers pdr@chromium.org
Reviewed-by: Nasko Oskov nasko@chromium.org
Cr-Commit-Position: refs/heads/main@{#1348862}