Reapply change to hide VM-only List implementation classes.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 66bab65176b42fa621294984494670b9fb1d01e9..b33dd0c475b57a10f3887a974e3a787b41c09434 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -586,12 +586,12 @@ RawError* Object::Init(Isolate* isolate) {
 
   cls = object_store->array_class();  // Was allocated above.
   name = Symbols::ObjectArray();
-  RegisterClass(cls, name, core_impl_lib);
+  RegisterPrivateClass(cls, name, core_impl_lib);
   pending_classes.Add(cls, Heap::kOld);
 
   cls = object_store->growable_object_array_class();  // Was allocated above.
   name = Symbols::GrowableObjectArray();
-  RegisterClass(cls, name, core_impl_lib);
+  RegisterPrivateClass(cls, name, core_impl_lib);
   pending_classes.Add(cls, Heap::kOld);
 
   cls = Class::New<ImmutableArray>();
@@ -599,7 +599,7 @@ RawError* Object::Init(Isolate* isolate) {
   cls.set_type_arguments_instance_field_offset(Array::type_arguments_offset());
   ASSERT(object_store->immutable_array_class() != object_store->array_class());
   name = Symbols::ImmutableArray();
-  RegisterClass(cls, name, core_impl_lib);
+  RegisterPrivateClass(cls, name, core_impl_lib);
   pending_classes.Add(cls, Heap::kOld);
 
   cls = object_store->one_byte_string_class();  // Was allocated above.