Merge branch '3.4' into 4.3

* 3.4:
  [DoctrineBridge] try to fix deprecations from doctrine/persistence
  [Translation] fix memoryleak in PhpFileLoader

Author: nicolas-grekas

Cloner/AbstractCloner.php

@@ -46,6 +46,7 @@ abstract class AbstractCloner implements ClonerInterface
         'Doctrine\Common\Proxy\Proxy' => ['Symfony\Component\VarDumper\Caster\DoctrineCaster', 'castCommonProxy'],
         'Doctrine\ORM\Proxy\Proxy' => ['Symfony\Component\VarDumper\Caster\DoctrineCaster', 'castOrmProxy'],
         'Doctrine\ORM\PersistentCollection' => ['Symfony\Component\VarDumper\Caster\DoctrineCaster', 'castPersistentCollection'],
+        'Doctrine\Persistence\ObjectManager' => ['Symfony\Component\VarDumper\Caster\StubCaster', 'cutInternals'],
 
         'DOMException' => ['Symfony\Component\VarDumper\Caster\DOMCaster', 'castException'],
         'DOMStringList' => ['Symfony\Component\VarDumper\Caster\DOMCaster', 'castLength'],