This test expects certain functions to be optimized, which does not
happen if we force array objects onto the slow path.

Bug: v8:7122
Change-Id: I716954fff564f1c4f0782b3452557ec89a3b4307
Reviewed-on: https://chromium-review.googlesource.com/796860
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49736}