Set global proxy internal field count based on the global object template.

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index 749188f6bf27fc514b196624e82cf0e5d74a36ab..2ceb75c300a3fc2c540862844559e3060b9fbad4 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -2178,12 +2178,10 @@ Handle<JSProxy> Factory::NewJSProxy(Handle<JSReceiver> target,
   return result;
 }
 
-
-Handle<JSGlobalProxy> Factory::NewUninitializedJSGlobalProxy() {
+Handle<JSGlobalProxy> Factory::NewUninitializedJSGlobalProxy(int size) {
   // Create an empty shell of a JSGlobalProxy that needs to be reinitialized
   // via ReinitializeJSGlobalProxy later.
-  Handle<Map> map =
-      NewMap(JS_GLOBAL_PROXY_TYPE, JSGlobalProxy::kSizeWithInternalFields);
+  Handle<Map> map = NewMap(JS_GLOBAL_PROXY_TYPE, size);
   // Maintain invariant expected from any JSGlobalProxy.
   map->set_is_access_check_needed(true);
   CALL_HEAP_FUNCTION(