only in patch2:
unchanged:
--- a/core/modules/system/tests/src/Functional/System/ErrorHandlerTest.php
+++ b/core/modules/system/tests/src/Functional/System/ErrorHandlerTest.php
@@ -35,12 +35,6 @@ public function testErrorHandler() {
       '%function' => 'Drupal\error_test\Controller\ErrorTestController->generateWarnings()',
       '%file' => drupal_get_path('module', 'error_test') . '/error_test.module',
     ];
-    $error_warning = [
-      '%type' => 'Warning',
-      '@message' => 'Division by zero',
-      '%function' => 'Drupal\error_test\Controller\ErrorTestController->generateWarnings()',
-      '%file' => drupal_get_path('module', 'error_test') . '/error_test.module',
-    ];
     $error_user_notice = [
       '%type' => 'User warning',
       '@message' => 'Drupal & awesome',