On Mac, we spend around 30% of lazy compile time in {ThreadTicks::Now}.
On Linux it's less severe, but still around 10%.
That's too much overhead for measurements that only show up in UKM, so
remove that.
The unused fields will be removed from the UKM events after the plumbing
on the chromium side has been removed.
R=ahaas@chromium.org, mlippautz@chromium.org
CC=ecmziegler@chromium.org
Bug: v8:13565
Change-Id: I2dad88d899482801888940499d2d1761ff075578
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4078966
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#84754}
068536f109