title: How to translate @Constraint messages in Symfony 2.8?
body: <p>The Cookbook show how <a href="http://symfony.com/doc/2.8/book/translation.html#translating-constraint-messages" rel="nofollow">to translate assert messages</a>, but how to do the same on @Constraint annotations on a class level? Example which is not working :</p>
  
  <pre><code> use Symfony\Bridge\Doctrine\Validator\Constraints as Constraint;
  
   /**
   * @Constraint\UniqueEntity(
   *     fields={"mobileDomainName"},
   *     errorPath="mobileDomainName",
   *     message="site.validation.mobileName.alreadyUsed"
   * )
   */
   class Site {
  </code></pre>
  
  <p>Thanks for your answers.</p>
  
  <p><strong>EDIT :</strong> translator is activated, all others classical calls worked (including Assert annotations).</p>