title: Missing argument 2 for a custom function
body: <p>So I am trying to replace the original post_title with a custom field right of the same post after saving the changes. However, I am getting the following error on the post page:</p>
  
  <p><strong>Warning: Missing argument 2 for wpse33385_filter_title() in $PATH/public_html/wp-content/themes/$THEME/functions.php on line 113</strong></p>
  
  <pre><code>// replaces the original post_title with the value of pac-short-title
  
  add_filter( 'the_title', 'wpse33385_filter_title', 10, 2);
  
  function wpse33385_filter_title( $title, $post_id )
  {
      if( $new_title = types_get_field_meta_value( 'pac-short-title', $post_id ) )
      {
          return $new_title;
      }
      return $title;
  }
  </code></pre>
  
  <p>I am confused because I have defined a number of arguments in the add_filter?</p>