Closed Bug 1598457 Opened 10 months ago Closed 10 months ago

[wpt-sync] Sync PR 20374 - [IntersectionObserver] Check containing block chain for stop node

Categories

(Core :: Layout, task, P4)

task

Tracking

()

RESOLVED FIXED
mozilla72
Tracking Status
firefox72 --- fixed

People

(Reporter: mozilla.org, Unassigned)

References

()

Details

(Whiteboard: [wptsync downstream])

Sync web-platform-tests PR 20374 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/20374
Details from upstream follow.

Chris Harrelson <chrishtr@chromium.org> wrote:

[IntersectionObserver] Check containing block chain for stop node

When doing a hit test to measure occlusion, the code previously
assumed that the hit test logic would always prevent descending into
the subtree of the stop node. That's not the case when parent and
child positioned objects are in the same stacking context and the
parent positioned object is the stop node. In that case the subtree
of the child positioned object will be traversed before the parent
positioned object.

When a hit is identified, we need to explicitly check whether it's a
containing block descendant of the stop node; and if so, reject the
hit.

NOTE: this is a clone of
https://chromium-review.googlesource.com/c/chromium/src/+/1914537
that I'm committing on behalf of szager@

BUG=1020784

Change-Id: Ic9270d7b6491be1b3364131fb20cd120fbb6d272

Reviewed-on: https://chromium-review.googlesource.com/1929643
WPT-Export-Revision: 528c0489964d521057bcfeffafdd0b0635bfccec

Component: web-platform-tests → Layout
Product: Testing → Core
Pushed by wptsync@mozilla.com:
https://hg.mozilla.org/integration/autoland/rev/651db543f34c
[wpt PR 20374] - [IntersectionObserver] Check containing block chain for stop node, a=testonly
https://hg.mozilla.org/integration/autoland/rev/294914c68c3b
[wpt PR 20374] - Update wpt metadata, a=testonly
Test result changes from PR not available.
Status: NEW → RESOLVED
Closed: 10 months ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla72
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