Landing define-class-fields microbencharks upstream before optimization so that
the benefit is visible.

Bug: v8:9888
Change-Id: Ie3bd2bd2cdd5710f43e398aa834985b5faa973d5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2999030
Commit-Queue: Joyee Cheung <joyee@igalia.com>
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#76267}