.../src/Normalizer/EntityReferenceItemNormalizer.php  | 19 ++-----------------
 1 file changed, 2 insertions(+), 17 deletions(-)

diff --git a/core/modules/hal/src/Normalizer/EntityReferenceItemNormalizer.php b/core/modules/hal/src/Normalizer/EntityReferenceItemNormalizer.php
index d103894..324e7f9 100644
--- a/core/modules/hal/src/Normalizer/EntityReferenceItemNormalizer.php
+++ b/core/modules/hal/src/Normalizer/EntityReferenceItemNormalizer.php
@@ -55,7 +55,7 @@ class EntityReferenceItemNormalizer extends FieldItemNormalizer implements UuidR
   public function __construct(LinkManagerInterface $link_manager, EntityResolverInterface $entity_Resolver, EntityTypeManagerInterface $entity_type_manager = NULL) {
     $this->linkManager = $link_manager;
     $this->entityResolver = $entity_Resolver;
-    $this->entityTypeManager = $entity_type_manager;
+    $this->entityTypeManager = $entity_type_manager ?: \Drupal::service('entity_type.manager');
   }
 
   /**
@@ -130,7 +130,7 @@ protected function targetEntityIsFieldable(EntityReferenceItem $item) {
     }
 
     // Otherwise, we need to get the class for the type.
-    $target_entity_type = $this->getEntityTypeManager()->getDefinition($target_entity_type_id);
+    $target_entity_type = $this->entityTypeManager->getDefinition($target_entity_type_id);
     $target_entity_type_class = $target_entity_type->getClass();
 
     return is_a($target_entity_type_class, FieldableEntityInterface::class, TRUE);
@@ -164,19 +164,4 @@ public function getUuid($data) {
     }
   }
 
-  /**
-   * Gets the entity type manager.
-   *
-   * @return \Drupal\Core\Entity\EntityTypeManagerInterface|mixed
-   *
-   * @internal
-   * @todo Remove in Drupal 9.0.0. Only exists to provide constructor BC.
-   */
-  protected function getEntityTypeManager() {
-    if (!isset($this->entityTypeManager)) {
-      $this->entityTypeManager = \Drupal::service('entity_type.manager');
-    }
-    return $this->entityTypeManager;
-  }
-
 }