tree 67462d95ab4cc9b60b287d90138ecc5c3a226b61
parent 0dd3ce58985ae5e76a3b59959636fb19d5c4ae0d
author Xianzhu Wang <wangxianzhu@chromium.org> 1711570742 -0700
committer Blink WPT Bot <blink-w3c-test-autoroller@chromium.org> 1711572610 -0700

[css-anchor-position] Basic support for position-visibility: no-overflow

https://github.com/w3c/csswg-drafts/issues/7758#issuecomment-1965540529
no-overflow hides the abspos if it overflows its inset-modified
containing block (after exhausting all position-try options, if
relevant). Note this value would apply even when using regular
abspos or fixedpos.

PaintLayer::SetInvisibleForPositionVisibility to track if the layer
needs to be invisible for any position-visibility constraint. The
function is called when the abspos needs to be invisible due to
no-overflow. The layer, as well certain descendant layers [1] in
containing block hierarchy will be skipped during hit-testing and
paint.

[1] We should skip all descendant layers in containing block
hierarchy, but this CL fails to skip self-painting descendant layers
if the layer is not a stacking context. The issue will be addressed
in a followup.

Bug: 329703412
Change-Id: Iee50ef89fbdb6a4c514b1940c45b0d9c41220383
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5398471
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1279183}