Remove the --no-error-notification flag.

pkg/analysis_server/test/integration/integration_test_methods.dart

Index: pkg/analysis_server/test/integration/integration_test_methods.dart
diff --git a/pkg/analysis_server/test/integration/integration_test_methods.dart b/pkg/analysis_server/test/integration/integration_test_methods.dart
index 14251bba346577299b2951a0648d9dd7c3d6577c..ea537a93c459652c4f3c6c1a978aaae7f1b4bc0e 100644
--- a/pkg/analysis_server/test/integration/integration_test_methods.dart
+++ b/pkg/analysis_server/test/integration/integration_test_methods.dart
@@ -608,9 +608,6 @@ abstract class IntegrationTestMixin {
    * included in the notification is always a complete list that supersedes any
    * previously reported errors.
    *
-   * It is only possible to unsubscribe from this notification by using the
-   * command-line flag --no-error-notification.
-   *
    * Parameters
    *
    * file (FilePath)