title: \u0022 instead of " " with JsonResponse symfony
body: <p>my problem is :
  The data returned have \u0022 instead of "".</p>
  
  <pre><code>$em=$this-&gt;getDoctrine()-&gt;getManager();
  $result = $em-&gt;getRepository('HomeBundle:Product')-&gt;findAll();
  
  $encoders = array(new XmlEncoder(), new JsonEncoder());
  $normalizers = array(new ObjectNormalizer());
  $serializer = new Serializer($normalizers, $encoders);
  
  $jsonContent = $serializer-&gt;serialize($result,'json');
  
  $response = new JsonResponse($jsonContent);
  $response-&gt;headers-&gt;set('Content-Type', 'application/json');
  return $response;
  </code></pre>
  
  <p>and that's what i get</p>
  
  <pre><code>"[{\u0022id\u0022:1,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:3},{\u0022id\u0022:2,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:5},{\u0022id\u0022:3,\u0022name\u0022:\u0022oppv\u0022,\u0022price\u0022:16},{\u0022id\u0022:4,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:6},{\u0022id\u0022:5,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:7},{\u0022id\u0022:6,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:34},{\u0022id\u0022:7,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:56},{\u0022id\u0022:8,\u0022name\u0022:\u0022opp\u0022,\u0022price\u0022:30}]"
  </code></pre>
  
  <p>thanks in advance for your help</p>