This avoids a deopt loop.

Bug: v8:7254
Change-Id: I9ab1dfc754c5ad63c451a9e2276aa1d7eb4c27b1
Reviewed-on: https://chromium-review.googlesource.com/966065Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51994}