The simulated C++ signature for generated code entry points should
rely on primitive values (as opposed to ObjectPtr).

Bug: v8:3770
Change-Id: I6f6f4dc8a93c7ba46bfc7052dc4745b16e9fd62f
Reviewed-on: https://chromium-review.googlesource.com/c/1386875Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#58409}