Fix warnings_checker.dart handling of multitests

tests/language/mixin_of_mixin_test.dart

Index: tests/language/mixin_of_mixin_test.dart
diff --git a/tests/language/mixin_of_mixin_test.dart b/tests/language/mixin_of_mixin_test.dart
index 2ea3f3fa60d7e71355491c3ca994335503ba62e2..a686cf0f5428468f5cadbe981ec8ebf686cb4fdd 100644
--- a/tests/language/mixin_of_mixin_test.dart
+++ b/tests/language/mixin_of_mixin_test.dart
@@ -35,26 +35,26 @@ class T6 extends D with M3 {} // extends a class which declares m3()
 
 main() {
   /// none: static type warning, ok
-  new T1().a(); // /// 01: static type warning, runtime error
-  new T1().b(); // /// 02: static type warning, runtime error
-  new T1().c(); // /// 03: static type warning, ok
-  new T2().a(); // /// 04: static type warning, runtime error
-  new T2().b(); // /// 05: static type warning, runtime error
-  new T2().c(); // /// 06: static type warning, runtime error
-  new T2().m2(); /// 07: static type warning, ok
-  new T3().a(); // /// 08: static type warning, runtime error
-  new T3().b(); // /// 09: static type warning, runtime error
-  new T3().c(); // /// 10: static type warning, runtime error
-  new T3().m3(); /// 11: static type warning, ok
-  new T4().a(); // /// 12: static type warning, runtime error
-  new T4().b(); // /// 13: static type warning, runtime error
-  new T4().c(); // /// 14: static type warning, ok
-  new T5().a(); // /// 15: static type warning, runtime error
-  new T5().b(); // /// 16: static type warning, runtime error
-  new T5().c(); // /// 17: static type warning, runtime error
-  new T5().m2(); /// 18: static type warning, ok
-  new T6().a(); // /// 19: static type warning, runtime error
-  new T6().b(); // /// 20: static type warning, runtime error
-  new T6().c(); // /// 21: static type warning, runtime error
-  new T6().m3(); /// 22: static type warning, ok
+  new T1().a(); // //# 01: static type warning, runtime error
+  new T1().b(); // //# 02: static type warning, runtime error
+  new T1().c(); // //# 03: static type warning, ok
+  new T2().a(); // //# 04: static type warning, runtime error
+  new T2().b(); // //# 05: static type warning, runtime error
+  new T2().c(); // //# 06: static type warning, runtime error
+  new T2().m2(); //# 07: static type warning, ok
+  new T3().a(); // //# 08: static type warning, runtime error
+  new T3().b(); // //# 09: static type warning, runtime error
+  new T3().c(); // //# 10: static type warning, runtime error
+  new T3().m3(); //# 11: static type warning, ok
+  new T4().a(); // //# 12: static type warning, runtime error
+  new T4().b(); // //# 13: static type warning, runtime error
+  new T4().c(); // //# 14: static type warning, ok
+  new T5().a(); // //# 15: static type warning, runtime error
+  new T5().b(); // //# 16: static type warning, runtime error
+  new T5().c(); // //# 17: static type warning, runtime error
+  new T5().m2(); //# 18: static type warning, ok
+  new T6().a(); // //# 19: static type warning, runtime error
+  new T6().b(); // //# 20: static type warning, runtime error
+  new T6().c(); // //# 21: static type warning, runtime error
+  new T6().m3(); //# 22: static type warning, ok
 }