Revert "[sandbox] Also enable the sandbox outside of Chromium builds"

This reverts commit 5b9401dd.

Reason for revert: A few memory tests flake on tsan (e.g. https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Linux64%20TSAN%20-%20isolates/20190/overview)

Original change's description:
> [sandbox] Also enable the sandbox outside of Chromium builds
>
> Drive-by: include the right header in sandboxed-pointer-inl.h and fix
> missing sandbox initialization in generate-bytecode-expectations.cc.
>
> Bug: v8:10391
> Change-Id: Ic39ba04b7c98eaa58ea3943189c23b297f581f5a
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3630082
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Commit-Queue: Samuel Groß <saelo@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#81216}

Bug: v8:10391
Change-Id: I22560a6bdcffbf71651f655bdf7d183d5c832620
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3714239
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Owners-Override: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81256}

BUILD.gn

@@ -501,8 +501,9 @@ if (v8_enable_sandbox == "") {
   # once that is enabled everywhere by default.
   # TODO(chromium:1325784) the sandbox is not currently supported in Chromium
   # on Fuchsia.
-  v8_enable_sandbox = v8_enable_pointer_compression_shared_cage &&
-                      v8_enable_external_code_space && target_os != "fuchsia"
+  v8_enable_sandbox =
+      build_with_chromium && v8_enable_pointer_compression_shared_cage &&
+      v8_enable_external_code_space && target_os != "fuchsia"
 }
 
 # Enable sandboxed pointers when the sandbox is enabled.

src/sandbox/sandboxed-pointer-inl.h

@@ -6,7 +6,7 @@
 #define V8_SANDBOX_SANDBOXED_POINTER_INL_H_
 
 #include "include/v8-internal.h"
-#include "src/common/ptr-compr-inl.h"
+#include "src/common/ptr-compr.h"
 #include "src/execution/isolate.h"
 #include "src/sandbox/sandboxed-pointer.h"
 

test/unittests/interpreter/generate-bytecode-expectations.cc

@@ -347,11 +347,6 @@ V8InitializationScope::V8InitializationScope(const char* exec_path)
   v8::V8::InitializeICUDefaultLocation(exec_path);
   v8::V8::InitializeExternalStartupData(exec_path);
   v8::V8::InitializePlatform(platform_.get());
-#ifdef V8_ENABLE_SANDBOX
-  if (!v8::V8::InitializeSandbox()) {
-    FATAL("Could not initialize the sandbox");
-  }
-#endif
   v8::V8::Initialize();
 
   v8::Isolate::CreateParams create_params;