core/modules/editor/src/Tests/EditorFileReferenceFilterTest.php | 4 ++--
 core/modules/filter/src/FilterProcessResult.php                 | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/core/modules/editor/src/Tests/EditorFileReferenceFilterTest.php b/core/modules/editor/src/Tests/EditorFileReferenceFilterTest.php
index d0bfbb5..52e3685 100644
--- a/core/modules/editor/src/Tests/EditorFileReferenceFilterTest.php
+++ b/core/modules/editor/src/Tests/EditorFileReferenceFilterTest.php
@@ -7,13 +7,13 @@
 
 namespace Drupal\editor\Tests;
 
-use Drupal\simpletest\DrupalUnitTestBase;
+use Drupal\simpletest\KernelTestBase;
 use Drupal\filter\FilterBag;
 
 /**
  * Tests for the EditorFileReference filter.
  */
-class EditorFileReferenceFilterTest extends DrupalUnitTestBase {
+class EditorFileReferenceFilterTest extends KernelTestBase {
 
   /**
    * Modules to enable.
diff --git a/core/modules/filter/src/FilterProcessResult.php b/core/modules/filter/src/FilterProcessResult.php
index d5c2544..71edc45 100644
--- a/core/modules/filter/src/FilterProcessResult.php
+++ b/core/modules/filter/src/FilterProcessResult.php
@@ -155,7 +155,7 @@ public function getCacheTags() {
    * @return $this
    */
   public function addCacheTags(array $cache_tags) {
-    $this->cacheTags = NestedArray::mergeDeep($this->cacheTags, $cache_tags);
+    $this->cacheTags = drupal_merge_attached($this->cacheTags, $cache_tags);
     return $this;
   }