This CL hardens the test facility in d8 for interface types for
the fast C API.

Bug: chromium:1201011
Change-Id: Ibfe1bb242f86b4a5edd0d195e049852430f8a2fe
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2843344
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74079}