diff --git a/core/modules/views/src/EventSubscriber/ViewsEntitySchemaSubscriber.php b/core/modules/views/src/EventSubscriber/ViewsEntitySchemaSubscriber.php
index b698c74..0d53f32 100644
--- a/core/modules/views/src/EventSubscriber/ViewsEntitySchemaSubscriber.php
+++ b/core/modules/views/src/EventSubscriber/ViewsEntitySchemaSubscriber.php
@@ -137,11 +137,11 @@ public function onEntityTypeDelete(EntityTypeInterface $entity_type) {
         $view->save();
       }
 
-      // Continue and look at all handlers and check whether the entity type
-      // disappears.
-      // @todo How can we ensure that we don't break views.
+      // Unset all handlers which point to no longer existing entity types.
+      // @todo How can we ensure that we don't break views, see
+      //   https://www.drupal.org/node/2401467
       foreach (array_keys($view->get('display')) as $display_id) {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -183,10 +183,16 @@ public function onFieldStorageDefinitionDelete(FieldStorageDefinitionInterface $
   }
 
   /**
+   * Updates views if a base table is renamed.
+   *
    * @param \Drupal\views\Entity\View[] $all_views
+   *   All views.
    * @param string $entity_type_id
+   *   The entity type ID.
    * @param string $old_base_table
+   *   The old base table name.
    * @param string $new_base_table
+   *   The new base table name.
    */
   protected function baseTableRename($all_views, $entity_type_id, $old_base_table, $new_base_table) {
     foreach ($all_views as $view) {
@@ -195,7 +201,7 @@ protected function baseTableRename($all_views, $entity_type_id, $old_base_table,
       }
 
       foreach (array_keys($view->get('display')) as $display_id)  {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -212,10 +218,17 @@ protected function baseTableRename($all_views, $entity_type_id, $old_base_table,
   }
 
   /**
+   *
+   * Updates views if a data table is renamed.
+   *
    * @param \Drupal\views\Entity\View[] $all_views
+   *   All views.
    * @param string $entity_type_id
+   *   The entity type ID.
    * @param string $old_data_table
+   *   The old data table name.
    * @param string $new_data_table
+   *   The new data table name.
    */
   protected function dataTableRename($all_views, $entity_type_id, $old_data_table, $new_data_table) {
     foreach ($all_views as $view) {
@@ -224,7 +237,7 @@ protected function dataTableRename($all_views, $entity_type_id, $old_data_table,
       }
 
       foreach (array_keys($view->get('display')) as $display_id)  {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -241,12 +254,14 @@ protected function dataTableRename($all_views, $entity_type_id, $old_data_table,
   }
 
   /**
+   * Updates views if a data table is added.
+   *
    * @param \Drupal\views\Entity\View[] $all_views
+   *   All views.
    * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
-   * @param string $data_table
-   * @throws \Drupal\Core\Entity\EntityStorageException
+   *   The entity type.
    */
-  protected function dataTableAddition($all_views, EntityTypeInterface $entity_type, EntityTypeInterface $original_entity_type, $data_table) {
+  protected function dataTableAddition($all_views, EntityTypeInterface $entity_type) {
     /** @var \Drupal\Core\Entity\Sql\SqlContentEntityStorage $storage */
     $entity_type_id = $entity_type->id();
     $storage = $this->entityManager->getStorage($entity_type_id);
@@ -257,7 +272,7 @@ protected function dataTableAddition($all_views, EntityTypeInterface $entity_typ
 
     foreach ($all_views as $view) {
       foreach (array_keys($view->get('display')) as $display_id)  {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -276,10 +291,22 @@ protected function dataTableAddition($all_views, EntityTypeInterface $entity_typ
     }
   }
 
+  /**
+   * Updates views if a data table is removed.
+   *
+   * @param \Drupal\views\Entity\View[] $all_views
+   *   All views.
+   * @param string $entity_type_id
+   *   The entity type ID.
+   * @param string $old_data_table
+   *   The name of the previous existing data table.
+   * @param string $base_table
+   *   The name of the base table.
+   */
   protected function dataTableRemoval($all_views, $entity_type_id, $old_data_table, $base_table) {
     foreach ($all_views as $view) {
       foreach (array_keys($view->get('display')) as $display_id)  {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -298,14 +325,19 @@ protected function dataTableRemoval($all_views, $entity_type_id, $old_data_table
   }
 
   /**
+   * Updates views if a field is removed.
+   *
    * @param \Drupal\views\Entity\View[] $all_views
+   *   All views.
    * @param string $entity_type_id
+   *   The entity type ID.
    * @param string $field_name
+   *   The name of the removed field.
    */
   protected function removeFieldStorage($all_views, $entity_type_id, $field_name) {
     foreach ($all_views as $view) {
       foreach (array_keys($view->get('display')) as $display_id)  {
-        $display =& $view->getDisplay($display_id);
+        $display = &$view->getDisplay($display_id);
         foreach (Views::getHandlerTypes() as $handler_type) {
           $handler_type = $handler_type['plural'];
           if (!isset($display['display_options'][$handler_type])) {
@@ -321,4 +353,5 @@ protected function removeFieldStorage($all_views, $entity_type_id, $field_name)
       }
     }
   }
+
 }