* Update web-platform-tests to revision b'50e91f3cfd1140cafc188516488f2dca289239af'
* Delete flaky result for css2/linebox/vertical-align-baseline-002
* Delete flaky result for html/rendering/bindings/the-textarea-element-0/cols-default.html.ini
* Delete flaky result for CSS2/lists/list-style-applies-to-001.xht.ini
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Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>
Most tests were only being run for layout-2013, not for layout-2020.
This wasn't great since layout-2020 is now the default.
So this patch unifies the lists of included tests for both layouts.
For layout-2013 this implies adding css/css-content/, css/css-logical/
and css/css-masking/clip/.
For layout-2020 this implies adding several additional css tests, and
also tests like dom/, js/, html/, etc.
