Fix warnings_checker.dart handling of multitests

tests/language_strong/getters_setters2_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // 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.
 
 import "package:expect/expect.dart";
 
 // Tests classes with getters and setters that do not have the same type.
 
 class A {
   int a() { return 37;}
@@ skipping 11 matching lines @@
   // OK, B is assignable to A
   void set field(B arg) { getterField = arg; }
 }
 
 class T2 {
   A getterField; 
   C setterField; 
   A get field { return getterField; }
 
   // Type C is not assignable to A
-  void set field(C arg) { setterField = arg; } /// 01: static type warning
+  void set field(C arg) { setterField = arg; } //# 01: static type warning
 }
 
 class T3 {
   B getterField; 
   B get field { return getterField; }
   // OK, A is assignable to B
   void set field(A arg) { getterField = arg; }
 }
 
 
 main() {
   T1 instance1 = new T1();
-  T2 instance2 = new T2(); /// 01: continued
+  T2 instance2 = new T2(); //# 01: continued
   T3 instance3 = new T3();
 
   instance1.field = new B();
   A resultA = instance1.field;
-  instance1.field = new A(); /// 03: dynamic type error
+  instance1.field = new A(); //# 03: dynamic type error
   B resultB = instance1.field;
 
   int result;
   result = instance1.field.a(); 
   Expect.equals(37, result);
 
   // Type 'A' has no method named 'b'
-  instance1.field.b(); /// 02: static type warning
+  instance1.field.b(); //# 02: static type warning
 
   instance3.field = new B();
   result = instance3.field.a();
   Expect.equals(37, result);
   result = instance3.field.b();
   Expect.equals(38, result);
 }