1657296 - [wpt-sync] Sync PR 24883 - Fieldset NG: Supports 'overflow' property properly

Status: NEW

(Core :: DOM: Core & HTML, task, P4)

Description

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

Sync web-platform-tests PR 24883 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/24883
Details from upstream follow.

Kent Tamura <[e-mail]> wrote:

Fieldset NG: Supports 'overflow' property properly

The 'overflow' property value should be propagated from a FIELDSET to
its anonymous fieldset content box, and its LEGEND should not be
scrolled if the anonymous fieldset content box is scrolled.

This CL consists of two parts:
A) Move out the rendered legend box from the anonymous fieldset content
box. The rendered legend should be the first child of the FIELDSET.
B) Propagate 'overflow' property value of a FIELDSET to its anonymous
fieldset content box, and disable the 'overflow' property for the
FIELDSET.

A)
The main change is LayoutNGFieldset::AddChild().
Because the rendered legend depends on the order in the children, we
need to reattach FIELDSET's LayoutObject whenever

• a LEGEND is added to a FIELDSET
  HTMLLegendElement::InsertedInto()
• a LEGEND is removed from a FIELDSET
  HTMLLegendElement::RemovedFrom()
• LEGEND's 'position' 'float' properties are changed
  ComputedStyle::NeedsReattachLayoutTree() and
  Element::RecalcOwnStyle()

This CL removes some code to handle the situation that the rendered
legend is a child of the anonymous fieldset content box.

• LayoutFieldset::FindInFlowLegend()
• LayoutObject::IsRenderedLegendInternal()
• GetLayoutObjectForFirstChildNode()
• GetLayoutObjectForParentNode()
• GetLayoutObjectForNextSiblingNode()
• NGBlockNode::PlaceChildrenInLayoutBox()

B)
In HTMLFieldSetElement::CustomStyleForLayoutObject(), we reset
'overflow' property values and store the original values.
LayoutNGFieldset::AddChild() copies the original values to the anonymous
fieldset content box.

Test changes
Update fieldset-content-before-legend.html and
fieldset-generated-content.html so that they are not affected by
rounding errors by fractional paddings and fractional letter widths.

Many testcases in NGFieldsetLayoutAlgorithmTest now has no anonymous
fieldset content boxes.

Bug: 875235, 1101976
Change-Id: Idc54069a75b2fba46897267fccd35c44c89b0c1f

Reviewed-on: https://chromium-review.googlesource.com/2336563
WPT-Export-Revision: 53715a94403c8b4d478a503d5a4cb2e69d27aa9d

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=421123845ac892c93fdbdb8216ec4090156db562

Comment 2

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

CI Results

Ran 12 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 1 tests and 1 subtests

Status Summary

Firefox

OK : 1
PASS: 1

Chrome

OK : 1
FAIL: 1

Safari

OK : 1
PASS: 1

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base