Fix warnings_checker.dart handling of multitests

tests/compiler/dart2js_extra/bounds_check_test.dart

Index: tests/compiler/dart2js_extra/bounds_check_test.dart
diff --git a/tests/compiler/dart2js_extra/bounds_check_test.dart b/tests/compiler/dart2js_extra/bounds_check_test.dart
index cfc79d62506dd7df2f039d84699754f6f0b1fea6..99223c8db8271df3c0f0c7e47a367658bafd3e66 100644
--- a/tests/compiler/dart2js_extra/bounds_check_test.dart
+++ b/tests/compiler/dart2js_extra/bounds_check_test.dart
@@ -4,14 +4,14 @@
 
 main() {
   var a = [0, 1];
-  a[-1]; //                         /// 01: runtime error
-  a[-1] = 4; //                     /// 02: runtime error
-  a[2]; //                          /// 03: runtime error
-  a[2] = 4; //                      /// 04: runtime error
-  checkIndex(a, -1); //             /// 05: runtime error
-  checkIndexedAssignment(a, -1); // /// 06: runtime error
-  checkIndex(a, 2); //              /// 07: runtime error
-  checkIndexedAssignment(a, 2); //  /// 08: runtime error
+  a[-1]; //                         //# 01: runtime error
+  a[-1] = 4; //                     //# 02: runtime error
+  a[2]; //                          //# 03: runtime error
+  a[2] = 4; //                      //# 04: runtime error
+  checkIndex(a, -1); //             //# 05: runtime error
+  checkIndexedAssignment(a, -1); // //# 06: runtime error
+  checkIndex(a, 2); //              //# 07: runtime error
+  checkIndexedAssignment(a, 2); //  //# 08: runtime error
   checkIndex(a, 0);
   checkIndexedAssignment(a, 0);
 }