The TPH needs to support the idea of 'code' objects, and the ability to query whether an object is of this type.

Bug: v8:9533
Change-Id: Ic36b235bd9640aa675a3ef0d8c3f6c98dd8cd862
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2013116Reviewed-by: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Steve Blackburn <steveblackburn@google.com>
Cr-Commit-Position: refs/heads/master@{#65948}