Fix pkg/analyzer_plugin/tool/spec/check_all_test.

pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart

Index: pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart
diff --git a/pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart b/pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart
index 391101bebbff26ef785c48550b7a959121fbcc5f..03106242d8d5690bf5c08649a254421c326735d7 100644
--- a/pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart
+++ b/pkg/analyzer_plugin/test/integration/support/integration_test_methods.dart
@@ -264,9 +264,6 @@ abstract class IntegrationTestMixin {
    * included in the notification is always a complete list that supersedes any
    * previously reported errors.
    *
-   * TODO: Decide whether we need to support the '--no-error-notification'
-   * option.
-   *
    * Parameters
    *
    * file (FilePath)