Make AnchoredPopupWindow update the popup layout when the view does.

This CL makes AnchoredPopupWindow listen to layout changes of the list
menu's content view, updating the layout of the popup in response.

Bug: 1316392
Change-Id: I541234181392b55df065fba52d08c436b32676ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3594445
Reviewed-by: Lijin Shen <lazzzis@google.com>
Commit-Queue: Scott Little <sclittle@chromium.org>
Auto-Submit: Scott Little <sclittle@chromium.org>
Reviewed-by: Theresa Sullivan <twellington@chromium.org>
Commit-Queue: Theresa Sullivan <twellington@chromium.org>
Cr-Commit-Position: refs/heads/main@{#994321}