[text-box-trim] Add text-box shorthand
As per the resolution at:
w3c/csswg-drafts#10675 (comment)
and the new spec at:
https://drafts.csswg.org/css-inline-3/#propdef-text-box
Bug: 358204934, 40254880
Change-Id: I641340e92855267627dbed6628b2df50c4608cec
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5776351
Reviewed-by: Anders Hartvoll Ruud andruud@chromium.org
Commit-Queue: Koji Ishii kojii@chromium.org
Cr-Commit-Position: refs/heads/main@{#1341553}