Reroll patch for 8.2.x https://www.drupal.org/node/2903942

fatal_error_on_8.2.x-2903942-3.patch

diff --git a/core/modules/views/src/Plugin/views/cache/CachePluginBase.php b/core/modules/views/src/Plugin/views/cache/CachePluginBase.php
index 87465ca06f..377d36f84e 100644
--- a/core/modules/views/src/Plugin/views/cache/CachePluginBase.php
+++ b/core/modules/views/src/Plugin/views/cache/CachePluginBase.php
@@ -4,6 +4,7 @@
 
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheableMetadata;
+use Drupal\Core\Entity\EntityInterface;
 use Drupal\views\Plugin\views\PluginBase;
 use Drupal\Core\Database\Query\Select;
 use Drupal\views\ResultRow;
@@ -303,7 +304,9 @@ public function getRowCacheTags(ResultRow $row) {
 
     if (!empty($row->_relationship_entities)) {
       foreach ($row->_relationship_entities as $entity) {
-        $tags = Cache::mergeTags($tags, $entity->getCacheTags());
+        if ($entity instanceof EntityInterface) {
+          $tags = Cache::mergeTags($tags, $entity->getCacheTags());
+        }
       }
     }
 
diff --git a/core/modules/views/src/Plugin/views/query/Sql.php b/core/modules/views/src/Plugin/views/query/Sql.php
index cfe593cc2e..604fffc898 100644
--- a/core/modules/views/src/Plugin/views/query/Sql.php
+++ b/core/modules/views/src/Plugin/views/query/Sql.php
@@ -5,6 +5,7 @@
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Database\Database;
+use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Form\FormStateInterface;
 use Drupal\views\Plugin\views\display\DisplayPluginBase;
@@ -1646,11 +1647,13 @@ public function getCacheMaxAge() {
   protected function getAllEntities() {
     $entities = [];
     foreach ($this->view->result as $row) {
-      if ($row->_entity) {
+      if ($row->_entity instanceof EntityInterface) {
         $entities[] = $row->_entity;
       }
       foreach ($row->_relationship_entities as $entity) {
-        $entities[] = $entity;
+        if ($entity instanceof EntityInterface) {
+          $entities[] = $entity;
+        }
       }
     }