Revert "Merge branch 'DDC-884'"

This reverts commit 3eea19dcfa654f00398c6b2fe380bbae16af74aa, reversing
changes made to b13c29944bab4d49eb8b59f89d7a520ac1bea778.

lib/Doctrine/ORM/EntityManager.php

@@ -725,6 +725,6 @@ class EntityManager implements ObjectManager
             throw new \InvalidArgumentException("Invalid argument: " . $conn);
         }
 
-        return new self($conn, $config, $conn->getEventManager());
+        return new EntityManager($conn, $config, $conn->getEventManager());
     }
 }