Fix fakebox hint label offset when rotating to landscape

The issue occurred only when the view was scrolled down in portrait
mode first.

Bug: 1424933
Change-Id: I5a7951222869e7004758d3547cb0e643d571388c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4347334


Reviewed-by: Chris Lu <thegreenfrog@chromium.org>
Commit-Queue: Jason Hu <hujasonx@google.com>
Cr-Commit-Position: refs/heads/main@{#1118924}