[css-align] 'justify-self' should override 'auto' margins

[dbaron]

The current rules for applying justify-self to blocks and applying it to absolutely positioned elements are structured so that auto margins override justify-self(with the possible exception of baseline alignment when orthogonal).

However, I tend to think:

• that the newer and more ergonomic API should override the older and less ergonomic API, and
• that it wouldn't be too difficult to structure the rules so that non-normal values of justify-self override auto margins,

so I would suggest that we change so that justify-self wins.

This also moves towards erasing the quirk that auto margins do safe alignment for normal flow blocks and for the inline dimension on abspos, but unsafe alignment for the block dimension on abspos.

[dbaron]

This also applies to the rules for align-self on absolutely positioned elements.

[fantasai]

Ok, so, while we fully sympathize with the desire to be rid of the terribleness in abspos margin alignment, the fact is that Grid and Flexbox already prioritize auto margins, and we feel it's definitely more important to remain consistent in this respect across all layout modes.

Let us know if you're satisfied with this resolution; otherwise please mark Agenda+ so we can discuss with the WG. :)

[dbaron]

OK... I guess I should have caught that in flexbox.