Main frame scrolling after the WebRender upgrade was broken because the
main frame no longer has content size content bounds and quirks mode
leads to a body with zero height.
Fixes#30368.
* Upgrade vendored version of WebRender
* Patch WebRender: upgrade version of gleam
* Restore hit testing implementation
* Fix WebRender warnings
* Adapt Servo to new WebRender
* Update results
* Add a workaround for #30313
This slightly expands text boundaries in order to take into account the
fact that layout isn't measuring glyph boundaries.
* 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>
