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.