[Partitioned Popins] The popin cannot open popins
We disallow this in the renderer/browser as it would cause issues with
the way modal popups work.
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: Ib6bac72db4ff3c48038c0e92c7fecb9d3b624ea8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5816450
Commit-Queue: Ari Chivukula arichiv@chromium.org
Reviewed-by: Nasko Oskov nasko@chromium.org
Reviewed-by: Philip Rogers pdr@chromium.org
Auto-Submit: Ari Chivukula arichiv@chromium.org
Commit-Queue: Nasko Oskov nasko@chromium.org
Cr-Commit-Position: refs/heads/main@{#1348976}