This change removes restrictions on using the column layout mode of
flexbox and adds an initial implementation of sizing for that flex
direction. There's a lot of missing pieces still, but in some cases this
does render column flexbox.
In particular, there are now two code paths for preferred widths
(intrinsic size) calcuation: one in the main axis (row) and one in
the cross axis (column) corresponding to the flex direciton with
horizontal writing modes.
In addition, `FlexItemBox::inline_content_sizes` is removed in favor of
making `sizing::outer_inline` /
`IndependentFormattingContext::outer_inline_content_sizes` generic
enough to handle using a different value for auto minimum sizes, which
flexbox needs.
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Oriol Brufau <obrufau@igalia.com>
