The bug was recently introduced in https://crrev.com/c/730716.

R=titzer@chromium.org

Bug: v8:6954
Change-Id: I9b77baac9fafefaab163700432ddef6e9e686901
Reviewed-on: https://chromium-review.googlesource.com/735540Reviewed-by: Ben Titzer <titzer@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48953}