Does step 5 of the linked bug.

Bug: chromium:1098923
Change-Id: I590cbaddb803f6343a61f7b49f7b8a4cb9773220
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2270704
Auto-Submit: Nico Weber <thakis@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#68571}