text-align: match-parent on root handles direction incorrectly

[Kiet Ho]

Failing WPT test: https://wpt.fyi/results/css/css-text/text-align/text-align-match-parent-root-rtl.html?label=master&label=experimental&aligned&q=text-align-match-parent-root-rtl.html

[Tim Nguyen (:ntim)]

We do use the direction of the parent, which is effectively why it's wrong for the WPT: https://webkit-search.igalia.com/webkit/rev/00d01db2338b1568d39aa439334f39f0353d0b00/Source/WebCore/style/StyleBuilderConverter.h#617-622

There's no parent in the WPT, so it should just behave like `text-align: start`.

[Kiet Ho]

(In reply to Tim Nguyen (:ntim) from comment #1)
> We do use the direction of the parent, which is effectively why it's wrong
> for the WPT:
> https://webkit-search.igalia.com/webkit/rev/
> 00d01db2338b1568d39aa439334f39f0353d0b00/Source/WebCore/style/
> StyleBuilderConverter.h#617-622
> 
> There's no parent in the WPT, so it should just behave like `text-align:
> start`.

I see what you mean now - I didn't want to give this a generic "failing WPT test" title, but I also didn't do any digging into the root cause, so I just named it according to my best guess.

[Tim Nguyen (:ntim)]

Pull request: https://github.com/WebKit/WebKit/pull/1208

[EWS]

Committed r295120 (251211@main): <https://commits.webkit.org/251211@main>

Reviewed commits have been landed. Closing PR #1208 and removing active labels.

[Radar WebKit Bug Importer]

<rdar://problem/94266878>