title: Missing argument 1 when injecting parameter in formtype
body: <p>Here my service definition :
  services.yml:</p>
  
  <pre><code>petapp.form.type.species:
  class: PetAppCoreBundle\Form\Type\SpeciesType
  arguments: ['%locale%']
  tags:
  - { name: form.type }
  </code></pre>
  
  <p>In config.yml</p>
  
  <pre><code>parameters:
  locale: en
  </code></pre>
  
  <p>In my Species Type :</p>
  
  <pre><code>/**
  * Default locale
  *
  * @var sting
  *
  */
  private $default_locale;
  
  /**
   * Constructor
   *
   * @param string $locale
   */
  public function __construct($locale)
  {
      $this-&gt;default_locale = $locale;
  }
  </code></pre>
  
  <p>I don't undertstand why the DIC does not call my FormType with %locale% parameter.
  I have the following error :</p>
  
  <pre><code>Warning: Missing argument 1 for PetApp\CoreBundle\Form\Type\SpeciesType::__construct(), called in /home/dev/petapp/vendor/symfony/symfony/src/Symfony/Component/Form/FormRegistry.php on line 90 and defined
  </code></pre>
  
  <p>I call createForm with new 2.8 syntax: (php 5.4)</p>
  
  <pre><code>$form = $this-&gt;createForm('PetApp\CoreBundle\Form\Type\SpeciesType',$species);
  </code></pre>
  
  <p>Do you have any idea about this issue ?
  Thanks.</p>
  
  <p>David</p>