diff --git a/core/lib/Drupal/Core/Entity/ContentEntityBase.php b/core/lib/Drupal/Core/Entity/ContentEntityBase.php
index e3b1f39..3133257 100644
--- a/core/lib/Drupal/Core/Entity/ContentEntityBase.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityBase.php
@@ -412,7 +412,14 @@ protected function getTranslatedField($property_name, $langcode) {
           $value = $this->values[$property_name][$langcode];
         }
         $field = \Drupal::typedData()->getPropertyInstance($this, $property_name, $value);
-        $field->setLangcode($default ? $this->language->id : $langcode);
+        if ($default) {
+          // If we are initializing the default language cache the variable is
+          // not populated, thus have no valid value to set.
+          $field->setLangcode(isset($this->language) ? $this->language->id : NULL);
+        }
+        else {
+          $field->setLangcode($langcode);
+        }
         $this->fields[$property_name][$langcode] = $field;
       }
     }
diff --git a/core/modules/edit/lib/Drupal/edit/Tests/EditLoadingTest.php b/core/modules/edit/lib/Drupal/edit/Tests/EditLoadingTest.php
index 329a29a..a52faa0 100644
--- a/core/modules/edit/lib/Drupal/edit/Tests/EditLoadingTest.php
+++ b/core/modules/edit/lib/Drupal/edit/Tests/EditLoadingTest.php
@@ -84,7 +84,7 @@ public function testUserWithoutPermission() {
 
     // HTML annotation must always exist (to not break the render cache).
     $this->assertRaw('data-edit-entity="node/1"');
-    $this->assertRaw('data-edit-id="node/1/body/xx-default/full"');
+    $this->assertRaw('data-edit-id="node/1/body/und/full"');
 
     // Retrieving the metadata should result in an empty 403 response.
     $post = array('fields[0]' => 'node/1/body/und/full');
@@ -141,7 +141,7 @@ public function testUserWithPermission() {
 
     // HTML annotation must always exist (to not break the render cache).
     $this->assertRaw('data-edit-entity="node/1"');
-    $this->assertRaw('data-edit-id="node/1/body/xx-default/full"');
+    $this->assertRaw('data-edit-id="node/1/body/und/full"');
 
     // There should be only one revision so far.
     $revisions = node_revision_list(node_load(1));
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
index 563f4f3..8189938 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityTranslationTest.php
@@ -217,20 +217,21 @@ protected function _testMultilingualProperties($entity_type) {
     $entity = entity_create($entity_type, array('name' => $name, 'user_id' => $uid));
     $entity->save();
     $entity = entity_load($entity_type, $entity->id());
-    $this->assertEqual($entity->language()->id, Language::LANGCODE_NOT_SPECIFIED, format_string('%entity_type: Entity created as language neutral.', array('%entity_type' => $entity_type)));
+    $default_langcode = $entity->language()->id;
+    $this->assertEqual($default_langcode, Language::LANGCODE_NOT_SPECIFIED, format_string('%entity_type: Entity created as language neutral.', array('%entity_type' => $entity_type)));
     $field = $entity->getTranslation(Language::LANGCODE_DEFAULT)->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name has been correctly stored as language neutral.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->getTranslation(Language::LANGCODE_DEFAULT)->get('user_id')->target_id, format_string('%entity_type: The entity author has been correctly stored as language neutral.', array('%entity_type' => $entity_type)));
     // As fields, translatable properties should ignore the given langcode and
     // use neutral language if the entity is not translatable.
     $field = $entity->getTranslation($langcode)->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name defaults to neutral language.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->getTranslation($langcode)->get('user_id')->target_id, format_string('%entity_type: The entity author defaults to neutral language.', array('%entity_type' => $entity_type)));
     $field = $entity->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name can be retrieved without specifying a language.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->get('user_id')->target_id, format_string('%entity_type: The entity author can be retrieved without specifying a language.', array('%entity_type' => $entity_type)));
 
     // Create a language-aware entity and check that properties are stored
@@ -238,20 +239,21 @@ protected function _testMultilingualProperties($entity_type) {
     $entity = entity_create($entity_type, array('name' => $name, 'user_id' => $uid, 'langcode' => $langcode));
     $entity->save();
     $entity = entity_load($entity_type, $entity->id());
-    $this->assertEqual($entity->language()->id, $langcode, format_string('%entity_type: Entity created as language specific.', array('%entity_type' => $entity_type)));
+    $default_langcode = $entity->language()->id;
+    $this->assertEqual($default_langcode, $langcode, format_string('%entity_type: Entity created as language specific.', array('%entity_type' => $entity_type)));
     $field = $entity->getTranslation($langcode)->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name has been correctly stored as a language-aware property.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->getTranslation($langcode)->get('user_id')->target_id, format_string('%entity_type: The entity author has been correctly stored as a language-aware property.', array('%entity_type' => $entity_type)));
     // Translatable properties on a translatable entity should use default
     // language if Language::LANGCODE_NOT_SPECIFIED is passed.
     $field = $entity->getTranslation(Language::LANGCODE_NOT_SPECIFIED)->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name defaults to the default language.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->getTranslation(Language::LANGCODE_NOT_SPECIFIED)->get('user_id')->target_id, format_string('%entity_type: The entity author defaults to the default language.', array('%entity_type' => $entity_type)));
     $field = $entity->get('name');
     $this->assertEqual($name, $field->value, format_string('%entity_type: The entity name can be retrieved without specifying a language.', array('%entity_type' => $entity_type)));
-    $this->assertEqual(Language::LANGCODE_DEFAULT, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
+    $this->assertEqual($default_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expect langcode.', array('%entity_type' => $entity_type)));
     $this->assertEqual($uid, $entity->get('user_id')->target_id, format_string('%entity_type: The entity author can be retrieved without specifying a language.', array('%entity_type' => $entity_type)));
 
     // Create property translations.
@@ -284,7 +286,7 @@ protected function _testMultilingualProperties($entity_type) {
       $field = $entity->getTranslation($langcode)->get('name');
       $this->assertEqual($properties[$langcode]['name'][0], $field->value, format_string('%entity_type: The entity name has been correctly stored for language %langcode.', $args));
       // Fields for the default entity langcode are seen as language neutral.
-      $field_langcode = ($langcode == $entity->language()->id) ? Language::LANGCODE_DEFAULT : $langcode;
+      $field_langcode = ($langcode == $entity->language()->id) ? $default_langcode : $langcode;
       $this->assertEqual($field_langcode, $field->getLangcode(), format_string('%entity_type: The field object has the expected langcode  %langcode.', $args));
       $this->assertEqual($properties[$langcode]['user_id'][0], $entity->getTranslation($langcode)->get('user_id')->target_id, format_string('%entity_type: The entity author has been correctly stored for language %langcode.', $args));
     }