Sync web-platform-tests PR 37651 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/37651
Details from upstream follow.

Frédéric Wang <fwang@igalia.com> wrote:

[mathml] Refactor parsing of mspace and mpadded attributes

Currently, the mspace and mpadded elements use different approaches
to parse the width/height/depth/lspace/voffset attributes:

• AddPropertyToPresentationAttributeStyle for the value (sometimes
  excluding values that ends with a '%' character).

• AddPropertyToPresentationAttributeStyle for a calc expression
  built from the values of the height and depth attributes.

• Using AddMathLengthToComputedStyle (sometimes accepting percentage)
  which relies on CSSParser::ParseLengthPercentage, but these parsing
  methods seem incorrect.

The initial goal was to use the default value when a percentage is
specified and this is what is currently specified in MathML Core
[1] [2]. However, the current implementation has bugs that make
percentage accepted in some cases [3] or unnecessarily mapping
invalid values to presentational hints.

This CL tries to bring more consistency on the parsing side by always
delegating the parsing of the attribute value to
CSSParser::ParseLengthPercentage before mapping it to presentational
hint or internal properties. The parsing parameter
AllowPercentages::kNo is used to ensure percentages are always
treated as invalid. CSSParser::ParseLengthPercentage is also refine to
always trim whitespaces, and check there is no remaining token after
the parsed \<length-percentage>.

This refactoring will facilitate specifying Chrome's behavior in
MathML Core regarding interaction with CSS width/height properties,
handling of percentages and use of presentational hints [4].

[1] https://w3c.github.io/mathml-core/#space-mspace
[2] https://w3c.github.io/mathml-core/#inner-box-and-requested-parameters
[3] crbug.com/1402998
[4] https://github.com/w3c/mathml-core/issues/75#issuecomment-1359541618

Bug: 6606, 1402998
Change-Id: Ibe4e49af4c3f4aeb5c153e10b4ba93d26db20849

Reviewed-on: https://chromium-review.googlesource.com/4120274
WPT-Export-Revision: 789122ba7c13ab6a1ad4878956447ea19cdc46a3

CI Results

Ran 0 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 3 tests

Status Summary

Firefox

OK : 1
PASS: 4
FAIL: 3

Chrome

OK : 1
PASS: 5
FAIL: 2

Safari

OK : 1
PASS: 4
FAIL: 3

Links

GitHub PR Head
GitHub PR Base

Details

New Tests That Don't Pass

• /mathml/presentation-markup/mpadded/mpadded-percentage-002.html [wpt.fyi]
  • width='200%' is interpreted as the default value: FAIL (Chrome: PASS, Safari: FAIL)
  • height='200%' is interpreted as the default value: FAIL (Chrome: PASS, Safari: FAIL)
  • depth='200%' is interpreted as the default value: FAIL (Chrome: PASS, Safari: FAIL)

https://hg.mozilla.org/mozilla-central/rev/ef3dc57c21dc
https://hg.mozilla.org/mozilla-central/rev/ebfd66be1e67