Empty slow element dictionary had the sticky bit set. This bit was
used to indicate that the dictionary cannot go to the fast mode either
because the dictionary had elements with attributed or elements at large
indices. There is no reason for the empty dictionary to have this bit set.
This causes bugs in some corner cases.

Bug: chromium:1003732
Change-Id: Ib29e1cda784869b9deb9361d8e6b5539f7154a38
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1833686Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64158}