CommentManager::addBodyField

public CommentManager::addBodyField($comment_type_id)

public function addBodyField($comment_type_id) {
  if (!FieldConfig::loadByName('comment', $comment_type_id, 'comment_body')) {
    // Attaches the body field by default.
    $field = $this->entityManager->getStorage('field_config')->create(array(
      'label' => 'Comment',
      'bundle' => $comment_type_id,
      'required' => TRUE,
      'field_storage' => FieldStorageConfig::loadByName('comment', 'comment_body'),
    ));
    $field->save();

    // Assign widget settings for the 'default' form mode.
    entity_get_form_display('comment', $comment_type_id, 'default')
      ->setComponent('comment_body', array(
        'type' => 'text_textarea',
      ))
      ->save();

    // Assign display settings for the 'default' view mode.
    entity_get_display('comment', $comment_type_id, 'default')
      ->setComponent('comment_body', array(
        'label' => 'hidden',
        'type' => 'text_default',
        'weight' => 0,
      ))
      ->save();
  }
}