Move prototype metadata from internal properties to prototype maps

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index 146b80b3ee16b621aa814c9ecc6613ab6b16d43c..59f9d68727b8d0bb84adf1f0ca429b85e99a84fe 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -51,6 +51,17 @@ Handle<Box> Factory::NewBox(Handle<Object> value) {
 }
 
 
+Handle<PrototypeInfo> Factory::NewPrototypeInfo(
+    Handle<JSObject> prototype_obj) {
+  Handle<PrototypeInfo> result =
+      Handle<PrototypeInfo>::cast(NewStruct(PROTOTYPE_INFO_TYPE));
+  result->set_prototype_object(*prototype_obj);
+  result->set_prototype_users(Smi::FromInt(0));
+  result->set_validity_cell(Smi::FromInt(0));
+  return result;
+}
+
+
 Handle<Oddball> Factory::NewOddball(Handle<Map> map,
                                     const char* to_string,
                                     Handle<Object> to_number,