/**
  * {@inheritdoc}
  */
 public function getDefinedLanguageTypesInfo()
 {
     if (!isset($this->languageTypesInfo)) {
         $defaults = parent::getDefinedLanguageTypesInfo();
         $info = $this->moduleHandler->invokeAll('language_types_info');
         $language_info = $info + $defaults;
         // Let other modules alter the list of language types.
         $this->moduleHandler->alter('language_types_info', $language_info);
         $this->languageTypesInfo = $language_info;
     }
     return $this->languageTypesInfo;
 }