title: Session flashdata doesn´t work on form submit
body: <p>I am using the ion-auth "library" for codeigniter (<a href="https://github.com/benedmunds/CodeIgniter-Ion-Auth" rel="nofollow">https://github.com/benedmunds/CodeIgniter-Ion-Auth</a>) and I am getting a trouble with the flashdata. This is a sumary of code:</p>
  
  <pre><code>public function reset_password($code = NULL)
  {
      if (!$code)show_404();
      $this-&gt;user = $this-&gt;ion_auth-&gt;forgotten_password_check($code);
      if ($this-&gt;user)
      {
          //setting the rules
          if ($this-&gt;form_validation-&gt;run() == false)
          {
              //more code
              $this-&gt;_get_csrf_nonce();
              /*
                One of the things this function (_get_csrf_nonce) makes is:
                $this-&gt;session-&gt;set_flashdata('csrfkey', $key);
                $this-&gt;session-&gt;set_flashdata('csrfvalue', $value); 
              */
              //The next thing is load the view with the form
          }
          else //form is running
          {
              echo "flashdata csrfkeyvalue: ".$this-&gt;session-&gt;flashdata('csrfvalue')."&lt;br&gt;";
              die;
              //more code, but not important by the moment
          }
      }
  }
  </code></pre>
  
  <p>Well, the echo of $this->session->flashdata('csrfvalue') when the form is submited allways show nothing.<br>
  If I make something like:</p>
  
  <pre><code>private function _get_csrf_nonce(){
      /*$this-&gt;load-&gt;helper('string');
      $key   = random_string('alnum', 8);
      $value = random_string('alnum', 20);
      $this-&gt;session-&gt;set_flashdata('csrfkey', $key);*/
      $this-&gt;session-&gt;set_flashdata('csrfvalue', $value);
      redirect(base_url("auth/test"));
      //return array($key =&gt; $value);
  }
  public function test()
  {
      echo "flashdata csrfkeyvalue: ".$this-&gt;session-&gt;flashdata('csrfvalue')."&lt;br&gt;";
  }
  </code></pre>
  
  <p>In this case... it works. The view I am using to the form is very very similar from this: <a href="https://github.com/benedmunds/CodeIgniter-Ion-Auth/blob/2/views/auth/reset_password.php" rel="nofollow">https://github.com/benedmunds/CodeIgniter-Ion-Auth/blob/2/views/auth/reset_password.php</a></p>
  
  <p>Thanks.</p>