Fix warnings_checker.dart handling of multitests

tests/language_strong/default_factory_test.dart

Index: tests/language_strong/default_factory_test.dart
diff --git a/tests/language_strong/default_factory_test.dart b/tests/language_strong/default_factory_test.dart
index bac3a04b773f783a2ad4323525b05139fd7ace80..820d741d9320f7a40fac26f1ccf27b2129e7b424 100644
--- a/tests/language_strong/default_factory_test.dart
+++ b/tests/language_strong/default_factory_test.dart
@@ -7,7 +7,7 @@ import "package:expect/expect.dart";
 // Dart test program for testing default factories.
 
 abstract class Vehicle {
-  factory Vehicle() = GoogleOne.Vehicle; /// 01: static type warning
+  factory Vehicle() = GoogleOne.Vehicle; //# 01: static type warning
 }
 
 
@@ -31,5 +31,5 @@ class GoogleOne implements SpaceShip {
 main() {
   Expect.equals(true, (new Bike.redOne()) is Bike);
   Expect.equals(true, (new SpaceShip()) is GoogleOne);
-  Expect.equals(true, (new Vehicle()) is Bike); /// 01: continued
+  Expect.equals(true, (new Vehicle()) is Bike); //# 01: continued
 }