diff --git a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
index a2bd021..05346aa 100644
--- a/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
+++ b/core/lib/Drupal/Core/Template/TwigNodeVisitor.php
@@ -16,7 +16,7 @@
  *
  * @see twig_render
  */
-class TwigNodeVisitor implements \Twig_BaseNodeVisitor {
+class TwigNodeVisitor extends \Twig_BaseNodeVisitor {
 
   /**
    * {@inheritdoc}
@@ -51,8 +51,7 @@ public function doLeaveNode(\Twig_Node $node, \Twig_Environment $env) {
         // Use our own escape filter that is SafeMarkup aware.
         $node->getNode('filter')->setAttribute('value', 'drupal_escape');
 
-        // Store that we have a filter active already that knows how to deal
-        // with render arrays.
+        // Store that we have a filter active already that knows how to deal with render arrays.
         $this->skipRenderVarFunction = TRUE;
       }
     }