The flag has been enabled by default since June 2018, see
https://crrev.com/c/1095650.

R=binji@chromium.org

Bug: v8:7625
Change-Id: I7cb4874db7f632b593f912e084b9fb7b8d568afe
Reviewed-on: https://chromium-review.googlesource.com/c/1402546Reviewed-by: Ben Smith <binji@chromium.org>
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58689}