chore: cherry-pick f5101995acd2 from chromium

[nornagon]

fix draggable regions not updating without layout

This fixes draggable regions not being updated when styles change, but there is
no layout as a result of the style change. Some changes to styles can cause a
change in draggable regions without causing a layout (e.g. applying the
-webkit-app-region: drag style to an element without changing its size).

Bug: 1051562
Change-Id: Ifdf835be9e6c762131529b4309c6579366b80d6d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3416279
Reviewed-by: Stefan Zager szager@chromium.org
Commit-Queue: Jeremy Apthorp jeremya@chromium.org
Cr-Commit-Position: refs/heads/main@{#963777}

Notes: Fixed draggable regions not updating unless a relayout occurs.

[nornagon]

Ref #32341

[release-clerk]

Release Notes Persisted

Fixed draggable regions not updating unless a relayout occurs.