Fix warnings_checker.dart handling of multitests

tests/language_strong/try_catch5_test.dart

Index: tests/language_strong/try_catch5_test.dart
diff --git a/tests/language_strong/try_catch5_test.dart b/tests/language_strong/try_catch5_test.dart
index 2b6d862b2457bd9b92496daff779b1a416fe7625..49b25356b86c5d9e47d1715704f98c58b8aee2c3 100644
--- a/tests/language_strong/try_catch5_test.dart
+++ b/tests/language_strong/try_catch5_test.dart
@@ -13,12 +13,12 @@ foo1() {
   var b = false;
   var entered = false;
   while (true) {
-    if (entered) return b; /// static warning
+    if (entered) return b; //# static warning
     b = 8 == a; // This expression should not be GVN'ed.
     try {
       try {
         a = 8;
-        return; /// static warning
+        return; //# static warning
       } finally {
         b = 8 == a;
         entered = true;