InvalidateRecordedSlots needs to invalidate old-to new objects
unconditionally. Checking slot_set_[OLD_TO_NEW] is not enough, since the
sweeping_slot_set_ could still contain slots.

ClearRecordedSlot in MigrateFastToFast is not necessary as well. This is
only required in DeleteObjectPropertyFast since we might potentially
shrink the object.

Bug: chromium:1008301,chromium:1008046
Change-Id: If2c757a619b52d070825e4faadce7710eae61a07
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1826717Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63985}