The list of forward declarations required in the generated file
bit-fields-tq.h is already somewhat unwieldy and will run into serious
problems when we attempt to use enums that are defined within classes,
such as JSDateTimeFormat::DateTimeStyle. After a brief discussion today,
the cleanest solution we arrived at is to generate macros instead.

Change-Id: I654e10efbab5a1a0a340fa565c51ff1da34badaa
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2050830Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Seth Brenith <seth.brenith@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#66240}