Use the DEFINE_FIELD_OFFSET_CONSTANTS macro to define the fields in the
BytecodeArray layout description.

Change-Id: I89ff2d7cd967aa1a503cbedd5d95dcd80f4d038c
Reviewed-on: https://chromium-review.googlesource.com/643130Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47713}