In heap-refs.cc, GetOwnFastDataPropertyFromHeap() bottlenecks reading
a fast property. To make it safe to use from the background thread we
need to verify the object didn't shrink, and risk an out of heap
bounds read.

Bug: v8:7790
Change-Id: Idebbe0ffea089bf2a70aa7d611618430169082fd
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2928185Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Michael Stanton <mvstanton@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75186}