Make scroll-timeline snapshotting tests align with spec and proposal#56000
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chromium-wpt-export-bot merged 1 commit intomasterfrom Nov 12, 2025
Merged
Make scroll-timeline snapshotting tests align with spec and proposal#56000chromium-wpt-export-bot merged 1 commit intomasterfrom
chromium-wpt-export-bot merged 1 commit intomasterfrom
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According to the current spec, scroll-timelines are update after scroll events are dispatched, but before style and layout is updated for the frame update. With the proposed change[1] in the HTML specification, the scroll-timelines are updated after a first style/layout update in the resizeObserver loop. We modify the scroll-timeline-snapshotting tests to allow them to pass for both timings. This reveals an issue with the current Blink implementation not matching the current spec, as we snapshot the timelines before the scroll events are dispatched. WebKit implements the current spec and still pass the tests after modification. [1] whatwg/html#11613 Bug: 384523570 Change-Id: I03b29b1f85527f9e54d597586d0764fc53f7776b Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7141779 Reviewed-by: Kevin Ellis <kevers@chromium.org> Commit-Queue: Rune Lillesveen <futhark@chromium.org> Cr-Commit-Position: refs/heads/main@{#1543753}
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According to the current spec, scroll-timelines are update after scroll
events are dispatched, but before style and layout is updated for the
frame update. With the proposed change[1] in the HTML specification,
the scroll-timelines are updated after a first style/layout update in
the resizeObserver loop.
We modify the scroll-timeline-snapshotting tests to allow them to pass
for both timings. This reveals an issue with the current Blink
implementation not matching the current spec, as we snapshot the
timelines before the scroll events are dispatched.
WebKit implements the current spec and still pass the tests after
modification.
[1] whatwg/html#11613
Bug: 384523570
Change-Id: I03b29b1f85527f9e54d597586d0764fc53f7776b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7141779
Reviewed-by: Kevin Ellis <kevers@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1543753}