[heap] Ensure ptr-compression and ro-heap sharing are mutually exclusive

Bug: v8:7464
Change-Id: Id191c185ebe811a7e8830cbdfd7751ee4f7b6060
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1602693Reviewed-by: Dan Elphick <delphick@chromium.org>
Commit-Queue: Maciej Goszczycki <goszczycki@google.com>
Cr-Commit-Position: refs/heads/master@{#61383}

BUILD.gn

@@ -236,6 +236,10 @@ assert(!v8_enable_lite_mode || v8_use_snapshot,
 assert(v8_use_snapshot || !v8_enable_shared_ro_heap,
        "Nosnapshot builds are not supported with shared read-only heap enabled")
 
+assert(
+    !v8_enable_pointer_compression || !v8_enable_shared_ro_heap,
+    "Pointer compression is not supported with shared read-only heap enabled")
+
 v8_random_seed = "314159265"
 v8_toolset_for_shell = "host"