Update all tests

tests/language_strong/async_or_generator_return_type_stacktrace_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import "package:expect/expect.dart";
 
-void badReturnTypeAsync() async {}  /// 01: static type warning
-void badReturnTypeAsyncStar() async* {}  /// 02: static type warning
-void badReturnTypeSyncStar() sync* {}  /// 03: static type warning
+void badReturnTypeAsync() async {}  //# 01: static type warning
+void badReturnTypeAsyncStar() async* {}  //# 02: static type warning
+void badReturnTypeSyncStar() sync* {}  //# 03: static type warning
 
 main() {
   try {
-    badReturnTypeAsync();  /// 01: continued
+    badReturnTypeAsync();  //# 01: continued
   } catch(e, st) {
     Expect.isTrue(e is TypeError, "wrong exception type");
     Expect.isTrue(st.toString().contains("badReturnTypeAsync"),
                   "missing frame");
   }
 
   try {
-    badReturnTypeAsyncStar();  /// 02: continued
+    badReturnTypeAsyncStar();  //# 02: continued
   } catch(e, st) {
     Expect.isTrue(e is TypeError, "wrong exception type");
     Expect.isTrue(st.toString().contains("badReturnTypeAsyncStar"),
                   "missing frame");
   }
 
   try {
-    badReturnTypeSyncStar();  /// 03: continued
+    badReturnTypeSyncStar();  //# 03: continued
   } catch(e, st) {
     Expect.isTrue(e is TypeError, "wrong exception type");
     Expect.isTrue(st.toString().contains("badReturnTypeSyncStar"),
                   "missing frame");
   }
 }