The multiplier should depend on the kTaggedSize.

Bug: v8:7703
Change-Id: I3a13e51d06c31b70f6191b23b1913e7bc35cdb8f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1708473
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62801}