Fix warnings_checker.dart handling of multitests

tests/language/static_top_level_test.dart

Index: tests/language/static_top_level_test.dart
diff --git a/tests/language/static_top_level_test.dart b/tests/language/static_top_level_test.dart
index d6e155818b97c1c8eb775e981ed4d9f3597d598c..6b0a791f275bfc26f1f1430abb6d226c719f1100 100644
--- a/tests/language/static_top_level_test.dart
+++ b/tests/language/static_top_level_test.dart
@@ -2,15 +2,15 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-static method() { } //                   /// 00: compile-time error
-static var field; //                     /// 01: compile-time error
-static const finalField = 42; //         /// 02: compile-time error
-static const constant = 123; //          /// 03: compile-time error
+static method() { } //                   //# 00: compile-time error
+static var field; //                     //# 01: compile-time error
+static const finalField = 42; //         //# 02: compile-time error
+static const constant = 123; //          //# 03: compile-time error
 
-static int typedMethod() => 87; //       /// 04: compile-time error
-static int typedField; //                /// 05: compile-time error
-static const int typedFinalField = 99; /// 06: compile-time error
-static const int typedConstant = 1; //   /// 07: compile-time error
+static int typedMethod() => 87; //       //# 04: compile-time error
+static int typedField; //                //# 05: compile-time error
+static const int typedFinalField = 99; //# 06: compile-time error
+static const int typedConstant = 1; //   //# 07: compile-time error
 
 void main() {
 }