/**
  * Retrieve block cache tags
  *
  * @return array
  */
 public function getCacheTags()
 {
     return array_merge(parent::getCacheTags(), $this->getItemsTags($this->getItemCollection()));
 }
 /**
  * Retrieve block cache tags
  *
  * @return array
  */
 public function getCacheTags()
 {
     $tags = parent::getCacheTags();
     $ids = $this->getAllIds();
     if (!empty($ids)) {
         foreach ($ids as $id) {
             $tags[] = Mage_Catalog_Model_Product::CACHE_TAG . '_' . $id;
         }
     }
     return $tags;
 }