doctrine/mongodb-odm — pull request #707 by aferrandini (2013-11-22 08:47:36+00:00)
Title: Fix issue with MongoId objects in UnitOfWork

When using references and embedded objects with references, you get this exception when trying to get the referenced object.

```
[Symfony\Component\Debug\Exception\ContextErrorException]
Warning: Illegal offset type in isset or empty in
./vendor/doctrine/mongodb-odm/lib/Doctrine/ODM/MongoDB/UnitOfWork.php line 1693
```