This is a partial reland of https://crrev.com/c/v8/v8/+/2199640 . It
allows scoped lookups to not crash during CompileCurrentAst, fixes the
formatting in an error message, and includes an extra line for
convenience when generating macros for bitfields.

Change-Id: I7ed9f7d76b3ce5e2cc0f2580d7ba1953da340ae8
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2216301Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#68018}