The build flag is on by default and the actual functionality is guarded
by a runtime flag.

Bug: v8:12612
Change-Id: I6adbd5b766f502400af32eeeb035edca3a3606ef
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3448383Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/main@{#79036}