The map of the HashTable is more a property of the HashTable than part
of its shape, so we can move its static map getter (for construction)
to to HashTable class itself.

Change-Id: I73f4aa7260d6ce749ef51961767fd37d1ab520e4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2289782
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68805}