Shared read-only heap is currently incompatible with pointer compression.
Enable sharing only if pointer compression is disabled.

Bug: v8:7464
Change-Id: I0866ac288a34eb92fc227e8beba57f4d72a69ef0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1635509Reviewed-by: Dan Elphick <delphick@chromium.org>
Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
Cr-Commit-Position: refs/heads/master@{#61963}