diff --git a/core/modules/taxonomy/taxonomy.module b/core/modules/taxonomy/taxonomy.module
index f070b69..a7fd46f 100644
--- a/core/modules/taxonomy/taxonomy.module
+++ b/core/modules/taxonomy/taxonomy.module
@@ -5,6 +5,7 @@
  * Enables the organization of content into categories.
  */
 
+use Drupal\taxonomy\VocabularyInterface;
 use Drupal\node\Plugin\Core\Entity\Node;
 use Drupal\taxonomy\Plugin\Core\Entity\Term;
 use Drupal\taxonomy\Plugin\Core\Entity\Vocabulary;
@@ -430,7 +431,7 @@ function taxonomy_vocabulary_delete_multiple(array $vids) {
  * term has multiple parents then the vocabulary will be given a hierarchy of
  * TAXONOMY_HIERARCHY_MULTIPLE.
  *
- * @param Drupal\taxonomy\Plugin\Core\Entity\Vocabulary $vocabulary
+ * @param Drupal\taxonomy\VocabularyInterface $vocabulary
  *   A taxonomy vocabulary entity.
  * @param $changed_term
  *   An array of the term structure that was updated.
@@ -438,7 +439,7 @@ function taxonomy_vocabulary_delete_multiple(array $vids) {
  * @return
  *   An integer that represents the level of the vocabulary's hierarchy.
  */
-function taxonomy_check_vocabulary_hierarchy(Vocabulary $vocabulary, $changed_term) {
+function taxonomy_check_vocabulary_hierarchy(VocabularyInterface $vocabulary, $changed_term) {
   $tree = taxonomy_get_tree($vocabulary->id());
   $hierarchy = TAXONOMY_HIERARCHY_DISABLED;
   foreach ($tree as $term) {