This adds support for fixing up tables so that internal table elements
that are not properly parented in the DOM have the correct box tree
structure according to the CSS Table specification [1]. Note that this
only comes into play when building the DOM via script, as HTML 5 has its
own table fixups that mean that the box tree construction fixups here
are not necessary.
There are no tests for this change. In general, it's hard to write tests
against the shape of the box tree, because it depends on the DOM. We
plan to test this via WPT tests once layout is complete.
1. https://drafts.csswg.org/css-tables/#table-internal-element
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
This is the first part of constructing the box tree for table layout. No
layout is actually done and the construction of tables is now hidden
behind a flag (in order to not regress WPT). Notably, this does not
handle anonymous table part construction, when the DOM does not reflect
a fully-formed table. That's part two.
Progress toward #27459.
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Manish Goregaokar <manishsmail@gmail.com>
