Adds traits for checking for Member,WeakMember, and UntracedMember
types.

This allows the embedder to specify its own traits and restrictions
around cppgc types.

Bug: chromium:1056170
Change-Id: Ibe60b774128f72f1398267edd81233c50fca6eb7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2532299Reviewed-by: Omer Katz <omerkatz@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71121}