diff --git a/core/lib/Drupal/Core/Access/AccessDependentInterface.php b/core/lib/Drupal/Core/Access/AccessDependentInterface.php
index 7afc93d4ef..6cb3f899c3 100644
--- a/core/lib/Drupal/Core/Access/AccessDependentInterface.php
+++ b/core/lib/Drupal/Core/Access/AccessDependentInterface.php
@@ -3,24 +3,39 @@
 namespace Drupal\Core\Access;
 
 /**
- * Interface for objects that are dependent on other accessible objects.
+ * Interface for AccessibleInterface objects that have an access dependency.
+ *
+ * Objects should implement this interface when their access depends on access
+ * to another object that implements \Drupal\Core\Access\AccessibleInterface.
+ * This interface simply provides the getter and setter methods for the access
+ * dependency object. Objects that implement this interface are responsible for
+ * checking access of the access dependency because the dependency may not take
+ * effect in all cases. For instance an entity may only need the access
+ * dependency set when it is embedded within another entity and its access
+ * should be dependent on access to the entity in which it is embedded.
+ *
+ * To check the access to the dependency the object implementing this interface
+ * can use code like this:
+ * @code
+ * $accessible->getAccessDependee()->access($op, $account, TRUE);
+ * @endcode
  */
-interface AccessDependentInterface {
+interface AccessDependentInterface extends AccessibleInterface {
 
   /**
-   * Sets the access dependee.
+   * Sets the access dependency.
    *
-   * @param \Drupal\Core\Access\AccessibleInterface $access_dependee
-   *   The access dependee.
+   * @param \Drupal\Core\Access\AccessibleInterface $access_dependency
+   *   The access dependency.
    */
-  public function setAccessDependee(AccessibleInterface $access_dependee);
+  public function setAccessDependency(AccessibleInterface $access_dependency);
 
   /**
-   * Gets the access dependee.
+   * Gets the access dependency.
    *
-   * @return \Drupal\Core\Access\AccessibleInterface
-   *   The access dependee.
+   * @return \Drupal\Core\Access\AccessibleInterface|null
+   *   The access dependency or NULL if none has been set.
    */
-  public function getAccessDependee();
+  public function getAccessDependency();
 
 }
diff --git a/core/lib/Drupal/Core/Access/AccessDependentTrait.php b/core/lib/Drupal/Core/Access/AccessDependentTrait.php
index 58b2e17ad1..0401736953 100644
--- a/core/lib/Drupal/Core/Access/AccessDependentTrait.php
+++ b/core/lib/Drupal/Core/Access/AccessDependentTrait.php
@@ -8,25 +8,25 @@
 trait AccessDependentTrait {
 
   /**
-   * The object that is depended on.
+   * The access dependency.
    *
    * @var \Drupal\Core\Access\AccessibleInterface
    */
-  protected $accessDependee;
+  protected $accessDependency;
 
   /**
    * {@inheritdoc}
    */
-  public function setAccessDependee(AccessibleInterface $access_dependee) {
-    $this->accessDependee = $access_dependee;
+  public function setAccessDependency(AccessibleInterface $access_dependency) {
+    $this->accessDependency = $access_dependency;
 
   }
 
   /**
    * {@inheritdoc}
    */
-  public function getAccessDependee() {
-    return $this->accessDependee;
+  public function getAccessDependency() {
+    return $this->accessDependency;
   }
 
 }
diff --git a/core/modules/block_content/block_content.install b/core/modules/block_content/block_content.install
index a2bbceae84..fd5d71f944 100644
--- a/core/modules/block_content/block_content.install
+++ b/core/modules/block_content/block_content.install
@@ -157,12 +157,12 @@ function block_content_update_8600() {
  * Update 'block_content' view to filter on new 'reusable' field.
  */
 function block_content_update_8601() {
-  $config_factory = \Drupal::configFactory();
-  $view = $config_factory->getEditable('views.view.block_content');
+  $view = \Drupal::configFactory()->getEditable('views.view.block_content');
   $base_table = 'block_content_field_data';
-  // Make sure the view's 'base_table' is correct. The default view could have
-  // been deleted and the view ID used for a different   view.
-  if ($view->get('base_table') !== $base_table) {
+  // Make sure the view's 'base_table' is correct and the View is not new. The
+  // default view could have been deleted and possibly the view ID could be used
+  // for a different view.
+  if ($view->get('base_table') !== $base_table or $view->isNew()) {
     return;
   }
   foreach ($view->get('display') as $display_name => $display) {
@@ -171,13 +171,13 @@ function block_content_update_8601() {
       ($display_name === 'default' || isset($display['display_options']['filters']))) {
       // Save off the base part of the config path we are updating.
       $base = "display.$display_name.display_options.filters.reusable";
-      $view->set("$base.id", 'reusable');
-      $view->set("$base.plugin_id", 'boolean');
-      $view->set("$base.table", $base_table);
-      $view->set("$base.field", "reusable");
-      $view->set("$base.value", "1");
-      $view->set("$base.entity_type", "block_content");
-      $view->set("$base.entity_field", "reusable");
+      $view->set("$base.id", 'reusable')
+        ->set("$base.plugin_id", 'boolean')
+        ->set("$base.table", $base_table)
+        ->set("$base.field", "reusable")
+        ->set("$base.value", "1")
+        ->set("$base.entity_type", "block_content")
+        ->set("$base.entity_field", "reusable");
     }
   }
   $view->save();
diff --git a/core/modules/block_content/block_content.module b/core/modules/block_content/block_content.module
index e867b32a8b..2478ef752d 100644
--- a/core/modules/block_content/block_content.module
+++ b/core/modules/block_content/block_content.module
@@ -10,7 +10,7 @@
 use Drupal\field\Entity\FieldStorageConfig;
 use Drupal\Core\Database\Query\SelectInterface;
 use Drupal\Core\Database\Query\AlterableInterface;
-use Drupal\Core\Database\Query\Condition;
+use Drupal\Core\Condition\ConditionInterface;
 
 /**
  * Implements hook_help().
@@ -112,7 +112,7 @@ function block_content_add_body_field($block_type_id, $label = 'Body') {
 /**
  * Implements hook_query_TAG_alter().
  *
- * Alter any query with all tags:
+ * Alters any query with all tags:
  * entity_reference, entity_query_block_content, entity_query_block_content.
  *
  * These queries should only return reusable blocks unless a condition on
@@ -128,17 +128,18 @@ function block_content_add_body_field($block_type_id, $label = 'Body') {
  * @see \Drupal\block_content\BlockContentAccessControlHandler
  */
 function block_content_query_block_content_access_alter(AlterableInterface $query) {
-  if ($query instanceof SelectInterface && $query->hasAllTags('entity_query_block_content', 'entity_reference') && array_key_exists('block_content_field_data', $query->getTables())) {
+  $data_table = \Drupal::entityTypeManager()->getDefinition('block_content')->getDataTable();
+  if ($query instanceof SelectInterface && $query->hasAllTags('entity_query_block_content', 'entity_reference') && array_key_exists($data_table, $query->getTables())) {
     $reusable_conditions = array_filter($query->conditions(), '_block_content_has_reusable_condition');
     if (empty($reusable_conditions)) {
-      // If no reusable condition set to one.
-      $query->condition('block_content_field_data.reusable', TRUE);
+      // If no reusable condition create a condition set to TRUE.
+      $query->condition("$data_table.reusable", TRUE);
     }
   }
 }
 
 /**
- * Utility function find nested conditions using the reusable field.
+ * Utility function to find nested conditions using the reusable field.
  *
  * @param mixed $condition
  *   The conditions to check.
@@ -151,7 +152,7 @@ function _block_content_has_reusable_condition($condition) {
     return FALSE;
   }
   $field = isset($condition['field']) ? $condition['field'] : NULL;
-  if (is_object($field) && $field instanceof Condition) {
+  if (is_object($field) && $field instanceof ConditionInterface) {
     return _block_content_has_reusable_condition($field->conditions());
   }
   if (isset($condition['#conjunction'])) {
diff --git a/core/modules/block_content/src/BlockContentAccessControlHandler.php b/core/modules/block_content/src/BlockContentAccessControlHandler.php
index 9f5487710d..cc2e9e5cfc 100644
--- a/core/modules/block_content/src/BlockContentAccessControlHandler.php
+++ b/core/modules/block_content/src/BlockContentAccessControlHandler.php
@@ -29,9 +29,9 @@ protected function checkAccess(EntityInterface $entity, $operation, AccountInter
     /** @var \Drupal\block_content\BlockContentInterface $entity */
     if ($entity->isReusable() === FALSE) {
       if (!$entity instanceof AccessDependentInterface) {
-        throw new \Exception("Non-reusable block entities must implement \Drupal\Core\Access\AccessDependentInterface for access control.");
+        throw new \LogicException("Non-reusable block entities must implement \Drupal\Core\Access\AccessDependentInterface for access control.");
       }
-      $dependee = $entity->getAccessDependee();
+      $dependee = $entity->getAccessDependency();
       if (empty($dependee)) {
         return AccessResult::forbidden("Non-reusable blocks must set an access dependee for access control.")->addCacheableDependency($dependee);
       }
diff --git a/core/modules/block_content/src/Entity/BlockContent.php b/core/modules/block_content/src/Entity/BlockContent.php
index 3e12cf9253..e382811106 100644
--- a/core/modules/block_content/src/Entity/BlockContent.php
+++ b/core/modules/block_content/src/Entity/BlockContent.php
@@ -207,7 +207,8 @@ public static function baseFieldDefinitions(EntityTypeInterface $entity_type) {
     $fields['reusable'] = BaseFieldDefinition::create('boolean')
       ->setLabel(t('Reusable'))
       ->setDescription(t('A boolean indicating whether this block is reusable.'))
-      ->setDefaultValue(TRUE);
+      ->setDefaultValue(TRUE)
+      ->setInitialValue(TRUE);
 
     return $fields;
   }
@@ -302,8 +303,7 @@ public function isReusable() {
    * {@inheritdoc}
    */
   public function setReusable($reusable = TRUE) {
-    $this->set('reusable', $reusable);
-    return $this;
+    return $this->set('reusable', $reusable);
   }
 
   /**