[text-box-trim] Use text-box-edge when trimming start
This patch uses the text-box-edge property when trimming the
block start.
The vertical flow isn't fully supported yet.
Bug: 40254880
Change-Id: I4f51aa15ceb681ec3db1c8751c64e2425679a5a2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5531306
Commit-Queue: Koji Ishii kojii@chromium.org
Reviewed-by: Kent Tamura tkent@chromium.org
Reviewed-by: Lingqi Chi lingqi@chromium.org
Cr-Commit-Position: refs/heads/main@{#1300556}