[DoctrineBridge] Fixed the entity provider to support proxies

Author: stof

src/Symfony/Bridge/Doctrine/Security/User/EntityUserProvider.php

@@ -100,6 +100,6 @@ public function refreshUser(UserInterface $user)
  */
  public function supportsClass($class)
  {
- return $class === $this->class;
+ return $class === $this->class || is_subclass_of($class, $this->class);
  }
 }