When creating a filler, we pass through whether we need to clear slots
in the old to new remembered set.

This patch adds a verification check that, when we claim we don't need
to clear slots, checks that no slots are set in the remembered set for
the range of the filler. Effectively, this is a range counterpart to
VerifyClearedSlot.

Change-Id: Id994c56d941988cc282463304bc7307a51943e99
Bug: chromium:1075999
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2139572
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67453}