Fix warnings_checker.dart handling of multitests

tests/language/import_self_test.dart

Index: tests/language/import_self_test.dart
diff --git a/tests/language/import_self_test.dart b/tests/language/import_self_test.dart
index ae25bc0e72d9a5672cbc5c188f9fc50c5a1cd47d..977efa6779d015a75325fb2bfd4d1313c8f09051 100644
--- a/tests/language/import_self_test.dart
+++ b/tests/language/import_self_test.dart
@@ -11,7 +11,7 @@ import "package:expect/expect.dart";
 
 // Eliminate the import of the unmodified file or else the analyzer
 // will generate the static warning in the import_self_test_none case.
-import "import_self_test.dart" as p; // /// 01: continued
+import "import_self_test.dart" as p; // //# 01: continued
 
 var _x = "The quick brown fox jumps over the dazy log";
 
@@ -21,8 +21,8 @@ main() {
   // Check that referencing p._x causes a warning from the analyzer,
   // and the runtime fails to resolve p._x, even though it refers to
   // top level variable _x of this file.
-  Expect.throws(() { t = p._x; }, // /// 01: static type warning
-                (e) => e is NoSuchMethodError); // /// 01: continued
+  Expect.throws(() { t = p._x; }, // //# 01: static type warning
+                (e) => e is NoSuchMethodError); // //# 01: continued
 
   Expect.isTrue(t.endsWith("Zwerg"));
 }