Fix warnings_checker.dart handling of multitests

tests/language/type_promotion_assign_test.dart

Index: tests/language/type_promotion_assign_test.dart
diff --git a/tests/language/type_promotion_assign_test.dart b/tests/language/type_promotion_assign_test.dart
index 51f0ee5d4b7dc8141fabeec913d56a1da7fbf2bf..d928fd2449c8df0e5edc4c48cb3a6bad7f38b427 100644
--- a/tests/language/type_promotion_assign_test.dart
+++ b/tests/language/type_promotion_assign_test.dart
@@ -27,21 +27,21 @@ void main() {
   A a = new E();
   if (a is B) {
     print(a.a);
-    print(a.b); /// 01: static type warning
+    print(a.b); //# 01: static type warning
     a = null;
   }
   if (a is B) {
     a = null;
     print(a.a);
-    print(a.b); /// 02: static type warning
+    print(a.b); //# 02: static type warning
   }
   if (a is B) {
     print(a.a);
-    print(a.b); /// 03: static type warning
+    print(a.b); //# 03: static type warning
     {
       a = null;
     }
     print(a.a);
-    print(a.b); /// 04: static type warning
+    print(a.b); //# 04: static type warning
   }
 }