Fix warnings_checker.dart handling of multitests

tests/language_strong/mixin_type_parameters_errors_test.dart

Index: tests/language_strong/mixin_type_parameters_errors_test.dart
diff --git a/tests/language_strong/mixin_type_parameters_errors_test.dart b/tests/language_strong/mixin_type_parameters_errors_test.dart
index f8ae1399b6c30a509ef1ded593bd8f1e6e9ee1e2..3a1692021acdb189b8800503807bda23b9ac75d2 100644
--- a/tests/language_strong/mixin_type_parameters_errors_test.dart
+++ b/tests/language_strong/mixin_type_parameters_errors_test.dart
@@ -6,17 +6,17 @@ class S<T> { }
 class M<U> { }
 
 class A<X> extends S<int> with M<double> { }
-class B<U, V> extends S with M<U, V> { } // /// 01: static type warning
-class C<A, B> extends S<A, int> with M { } // /// 02: static type warning
+class B<U, V> extends S with M<U, V> { } // //# 01: static type warning
+class C<A, B> extends S<A, int> with M { } // //# 02: static type warning
 
 class F<X> = S<X> with M<X>;
-class G = S<int> with M<double, double>; // /// 05: static type warning
+class G = S<int> with M<double, double>; // //# 05: static type warning
 
 main() {
   var a;
   a = new A();
   a = new A<int>();
-  a = new A<String, String>(); // /// 03: static type warning
+  a = new A<String, String>(); // //# 03: static type warning
   a = new F<int>();
-  a = new F<int, String>(); //  /// 04: static type warning
+  a = new F<int, String>(); //  //# 04: static type warning
 }