This patch just adds the new root paintable and updates the tests
expectations. The next patch will move painting logic from the layout
viewport to the paint viewport.
Changing `calculate_min_content_heigh()` and
`calculate_min_content_heigh()` to accept width as `CSSPixels`, instead
of `AvailableSize` that might be indefinite, makes it more explicit
that width is supposed to be known by the time height is measured.
This change has a bit of collateral damage which is rows height
calculation regression in `table/inline-table-width` that worked before
by accident.
The shortcut we put in place didn't resolve percentage widths and
ignored border spacing. We can still return early after we compute the
width per the specifications.
Since there are no table-specific boxes anymore it would be nice to
output their types additionally in layout dump so we can tell table
boxes from "regular" boxes.
Solves conflict in layout tree "type system" when elements <label> (or
<button>) can't have `display: table` because Box can't be
Layout::Label (or Layout::ButtonBox) and Layout::TableBox at the same
time.
Width of table wrapper need to be set to to calculate width of table
box inside. Otherwise TFC will set wrong width assuming width of
containing block is 0.
