Allow _unfencedTop navigation in all fenced frames.
Previously, only "opaque ads" fenced frames could navigate the _unfencedTop target, but we should allow all fenced frames to
do so.
While writing the spec for _unfencedTop, we re-discovered this limitation, and it was unclear why it existed in the first place. I wrote the spec change to allow the new keyword in all fenced frame types, and this change updates the Chromium implementation to match.
Bug: 380896847
Change-Id: Id02563a3e217042f9c8ac136929f168a7c899d51
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6017449
Reviewed-by: Liam Brady lbrady@google.com
Reviewed-by: Arthur Sonzogni arthursonzogni@chromium.org
Reviewed-by: Dominic Farolino dom@chromium.org
Commit-Queue: Andrew Verge averge@chromium.org
Cr-Commit-Position: refs/heads/main@{#1390314}