Fix warnings_checker.dart handling of multitests

tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart

Index: tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart
diff --git a/tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart b/tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart
index 1c3b53c2cd7dc987757d60382a2b34b6a27914c9..aa616e228d7082b1731d5b3a579028cc15d33b84 100644
--- a/tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart
+++ b/tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart
@@ -23,7 +23,7 @@ main() {
 
   // The following code does not currenty work on the VM, because it does not
   // support MirrorsUsed (see dartbug.com/16048).
-  Mirror barMirror = thisLibrary.declarations[#Bar]; //             /// 01: ok
-  Expect.isTrue(barMirror == null, //                               /// 01: continued
-                'Bar should not be emitted due to MirrorsUsed.'); /// 01: continued
+  Mirror barMirror = thisLibrary.declarations[#Bar]; //             //# 01: ok
+  Expect.isTrue(barMirror == null, //                               //# 01: continued
+                'Bar should not be emitted due to MirrorsUsed.'); //# 01: continued
 }