Add warning and error markers to some tests

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 5aa16e91e234a4e49ed005d4e37313cb38a0cbe0..2b6d862b2457bd9b92496daff779b1a416fe7625 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;
+    if (entered) return b; /// static warning
     b = 8 == a; // This expression should not be GVN'ed.
     try {
       try {
         a = 8;
-        return;
+        return; /// static warning
       } finally {
         b = 8 == a;
         entered = true;