/**
  * Gets instance of class.
  *
  * @return WP_Google_Analytics Instance of the class.
  */
 public static function get_instance()
 {
     if (null == self::$instance) {
         self::$instance = new self();
     }
     return self::$instance;
 }
 /**
  * Enqueues scripts.
  */
 public function __enqueue_scripts()
 {
     $wp_enqueue_util = WP_Enqueue_Util::get_instance();
     $wp_google_analytics = WP_Google_Analytics::get_instance();
     $handle = $wp_google_analytics->get_slug() . '-scripts';
     $relative_path = __DIR__ . '/../site/js/';
     $filename = 'bundle.min.js';
     $filename_debug = 'bundle.concat.js';
     $dependencies = array();
     $version = $wp_google_analytics->get_version();
     $tracking_id = apply_filters('wp_google_analytics_tracking_id', '');
     if (empty($tracking_id)) {
         return;
     }
     $data = array('options' => array('trackingId' => $tracking_id));
     $options = new WP_Enqueue_Options($handle, $relative_path, $filename, $filename_debug, $dependencies, $version);
     $options->set_localization($wp_google_analytics->get_localization_handle(), $data);
     $wp_enqueue_util->enqueue_script($options);
 }