Pull in test_reflective_loader 0.0.4 and switch analyzer to it.

pkg/analyzer/test/src/summary/api_signature_test.dart

Index: pkg/analyzer/test/src/summary/api_signature_test.dart
diff --git a/pkg/analyzer/test/src/summary/api_signature_test.dart b/pkg/analyzer/test/src/summary/api_signature_test.dart
index eabb8053cb1fb95fbef9b4d6876b5790240e533d..a8c3459ce7f2ac0da3b22fb67a63685752dd6ef6 100644
--- a/pkg/analyzer/test/src/summary/api_signature_test.dart
+++ b/pkg/analyzer/test/src/summary/api_signature_test.dart
@@ -8,13 +8,12 @@ import 'package:analyzer/src/summary/api_signature.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:convert/convert.dart';
 import 'package:crypto/crypto.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
 import 'package:unittest/unittest.dart';
 
-import '../../reflective_tests.dart';
-
 main() {
   groupSep = ' | ';
-  runReflectiveTests(ApiSignatureTest);
+  defineReflectiveTests(ApiSignatureTest);
 }
 
 @reflectiveTest