- Make explicit that Code::bytecode_offset_table is only used with
  sparkplug code.
- Add more DCHECKs on CodeBuilder setter
- Code::source_position_table is always a ByteArray

Bug: v8:11429
Change-Id: I27f84f0d6e325ca5b616412084227b9a7198d367
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2721769Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73217}