Lock Objects during serialization

old behaviour was to only lock arrays, dictionaries and namespaces but not other objects

(cherry picked from commit 91296c2a25)

lib/base/serializer.cpp

@@ -146,6 +146,8 @@ static Object::Ptr SerializeObject(const Object::Ptr& input, int attributeTypes,
 	DictionaryData fields;
 	fields.reserve(type->GetFieldCount() + 1);
 
+	ObjectLock olock(input);
+
 	for (int i = 0; i < type->GetFieldCount(); i++) {
 		Field field = type->GetFieldInfo(i);