Bug 1935098 [wpt PR 49518] - ::column pseudo element parsing and computed style tests, a=testonly

Automatic update from web-platform-tests
::column pseudo element parsing and computed style tests

Allowing ::column on ::before elements is not specifically mentioned in
the spec, but a ::before element can be a multicol scroll container with
generated content.

There is also an assumption here that all properties fully cascade even
if just a few actually have an effect.

Bug: 365680822, 382090952
Change-Id: I73d725d4bbf071016d53fc5183f2b9cea177f9ce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6068466
Reviewed-by: Daniil Sakhapov <sakhapovchromium.org>
Commit-Queue: Rune Lillesveen <futharkchromium.org>
Cr-Commit-Position: refs/heads/main{#1391571}

--

wpt-commits: 1d55057f6bd6600ac536dc82a6b3e80dac095abe
wpt-pr: 49518

UltraBlame original commit: 1f249b308e8890b706204126887fc54ffeb75238

Author: marco-c

testing/web-platform/tests/css/css-multicol/parsing/column-pseudo-computed.html

@@ -0,0 +1,368 @@
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