The Code::constant_pool() segfaulted on configurations with disabled
external code space when it was called on mallocced copy of a Code
object.

Bug: v8:11880
Change-Id: I86919002ef080486f1e4532c3a2d3352f4526508
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3772004
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Patrick Thier <pthier@chromium.org>
Commit-Queue: Patrick Thier <pthier@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81811}