Also added != 0 for readability in checks like:
  if (FIELD_SIZE(kFooOffset) != 0) {...}

Bug: v8:8477, v8:8562
Change-Id: Ibc305103475e6ec029e89e7ad095ec0a1fa30189
Reviewed-on: https://chromium-review.googlesource.com/c/1382743
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58360}