Especially, this requires having the __proto__s of functions serialized.

Drive-by fix (gc stress): Handlify IterateBuiltinObjects.

Bug: v8:11525
Change-Id: I8dc50b9144d17134a7c9b8fdbabe23f5e44f197f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3644613Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80608}