title: Symfony Twig: "Defining the initRuntime() method in the "form" extension is deprecated"
body: <p>After updating everything in my Symfony project by command:</p>
  
  <pre><code>composer update
  </code></pre>
  
  <p>I have one information about use of deprecated method in my profiler. Thats how it's looking:</p>
  
  <blockquote>
    <p>DEPRECATED - Defining the initRuntime() method in the "form" extension is deprecated. Use the <code>needs_environment</code> option to get the Twig_Environment instance in filters, functions, or tests; or explicitly implement Twig_Extension_InitRuntimeInterface if needed (not recommended).  -<br />
    Called from Twig_Environment::initRuntime() at line 408<br />
    Called from Twig_Environment::loadTemplate() at line 126<br />
    Called from TwigEngine::load() at line 50<br />
    Called from TwigEngine::render() at line 67<br />
    Called from TwigEngine::render() at line 50<br />
    Called from TimedTwigEngine::render() at line 92<br />
    Called from TwigEngine::renderResponse() at line 176<br />
    Called from Controller::render() at line 35<br />
    Called from SecurityController::loginAction()<br />
    Called from call_user_func_array() at line 3054<br />
    Called from HttpKernel::handleRaw() at line 3016<br />
    Called from HttpKernel::handle() at line 3165<br />
    Called from ContainerAwareHttpKernel::handle() at line 2406<br />
    Called from Kernel::handle() at line 28</p>
  </blockquote>
  
  <p>I tried to found the file which generates this message. This is in
  <strong>./vendor/twig/twig/lib/Twig/Environment.php</strong></p>
  
  <p>And the line is:</p>
  
  <pre><code>    (407) if (!$this-&gt;runtimeInitialized) {
      (408)     $this-&gt;initRuntime();
      (409) }
  </code></pre>
  
  <p>And I don't know how to correct it.</p>