It shipped in Chrome 71.

Bug: v8:5537
Change-Id: Ia78c58dc0af941ec87c05c933419f7e93d2b26f8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1675951
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Auto-Submit: Mathias Bynens <mathias@chromium.org>
Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62374}