[serializer] allocate global proxy with the expected size.

src/heap/heap-inl.h

Index: src/heap/heap-inl.h
diff --git a/src/heap/heap-inl.h b/src/heap/heap-inl.h
index 90d19280398d1d312d5ce9a6f9f1905fa62b38bd..02e684a3b9d54c46b447f3bf1e79cfdbf9a23fd8 100644
--- a/src/heap/heap-inl.h
+++ b/src/heap/heap-inl.h
@@ -812,9 +812,16 @@ int Heap::GetNextTemplateSerialNumber() {
 
 void Heap::SetSerializedTemplates(FixedArray* templates) {
   DCHECK_EQ(empty_fixed_array(), serialized_templates());
+  DCHECK(isolate()->serializer_enabled());
   set_serialized_templates(templates);
 }
 
+void Heap::SetSerializedGlobalProxySizes(FixedArray* sizes) {
+  DCHECK_EQ(empty_fixed_array(), serialized_global_proxy_sizes());
+  DCHECK(isolate()->serializer_enabled());
+  set_serialized_global_proxy_sizes(sizes);
+}
+
 void Heap::CreateObjectStats() {
   if (V8_LIKELY(FLAG_gc_stats == 0)) return;
   if (!live_object_stats_) {