[css-scroll-snap] Change Proposal Diffs

Dear CSS Working Group,

I have prepared for our discussions next week an annotated diff
of the two specs that were resolved to be merged, which should be
current as of today.
   https://drafts.csswg.org/css-scroll-snap/diff

I look forward to formally resolving the remaining outstanding
changes next week so that we can finalize this module (which
you assured me last year was a very urgent, high priority and
therefore due for completion six months ago), and anticipate
your enthusiastic cooperation in this endeavor!

~fantasai