GCInfo and its related infrastructure is used to record information
about types. Currently, we store finalization and vtable information.
Future changes will introduce naming and tracing, similar to Oilpan in
Blink.

Information is stored in a process-wide global table that is
maintained at runtime. For static builds such information can be
recorded in the binary without the runtime overhead which is future
work.

This ports `third_party/blink/renderer/platform/heap/gc_info.{h,cc}`
on a semantic level. In addition to adjusting to V8's needs, we also
re-commit the already filled parts of the info table as read-only when
possible, making it harder to override type information.

Bug: chromium:1056170
Change-Id: Ib01eb24e6f8a94a4a647efde7af37689f8c20ba2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2111214
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Hannes Payer <hpayer@chromium.org>
Reviewed-by: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#66847}