1750971 - [wpt-sync] Sync PR 32452 - Fix the fundamental compositing issue for resizable iframes

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, task, P4)

Description

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Sync web-platform-tests PR 32452 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/32452
Details from upstream follow.

Xianzhu Wang <[e-mail]> wrote:

Fix the fundamental compositing issue for resizable iframes

Stop forcing self-painting layer for iframes with resizers.

Most part of this CL is to keep resizer hit testing of iframe working.
Previously it was handled in PaintLayer::HitTestLayer() only. Now we
make it also work in the LayoutObject hit testing code path with the
following modifications:

• LayoutBlock::HitTestOverflowControl() is moved to LayoutBox because
  iframes (which are not LayoutBlock) need the implementation.
• Conditions before and in HitTestOverflowControls() are adjusted to
  support iframes (which have PaintLayerScrollableArea but are not
  scrollable by themselves).
• LayoutEmbeddedContent::NodeAtPointOverEmbeddedContentView() is
  modified to exclude resizers.

fast/css/resize-corner-tracking.html is the test covering iframe
resizer hit-testing. It's modified to a ref test, and a test case for
non-self-painting scroller with self-painting child is added to
ensure no regressions.

Bug: 1286988
Change-Id: Iab28803a0228ed7ed052e5065894f8eb7f97daf3
Reviewed-on: https://chromium-review.googlesource.com/3385656
WPT-Export-Revision: ea09db730eac2fc87d7c44174594e662631b7e96

Comment 1

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

Pushed to try (stability) https://treeherder.mozilla.org/#/jobs?repo=try&revision=d048da72170f87b61b6b3f5c6e95bf25deb7801d

Comment 2

[Web Platform Test Sync Bot [:wpt-sync] (Matrix: #interop:mozilla.org)]

CI Results

Ran 11 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 1 tests

Status Summary

Firefox

PASS: 1

Chrome

FAIL: 1

Safari

FAIL: 1

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Comment 3

[Iulian Moraru]

https://hg.mozilla.org/mozilla-central/rev/bdc72c453e2d