Fix warnings_checker.dart handling of multitests

tests/language/type_variable_bounds2_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";
 
 // Test of parameterized types with invalid bounds.
 
 abstract class J<T> { }
 
 abstract class K<T> { }
 
 abstract class I<T
-  extends num /// 00: continued
-  extends num /// 01: continued
-  extends num /// 02: continued
-  extends num /// 03: continued
-  extends num /// 04: continued
-  extends num /// 05: continued
-  extends num /// 06: continued
+  extends num //# 00: continued
+  extends num //# 01: continued
+  extends num //# 02: continued
+  extends num //# 03: continued
+  extends num //# 04: continued
+  extends num //# 05: continued
+  extends num //# 06: continued
 > { }
 
 class A<T> implements I<T>, J<T> {
 }
 
 main() {
   var a = new A<String>();
 
   {
-    I i = a; // /// 00: dynamic type error, static type warning
-    J j = a; // /// 01: static type warning
-    K k = a; // /// 02: dynamic type error, static type warning
+    I i = a; // //# 00: dynamic type error, static type warning
+    J j = a; // //# 01: static type warning
+    K k = a; // //# 02: dynamic type error, static type warning
 
     // In production mode, A<String> is subtype of I, error in checked mode.
-    var x = a is I; // /// 03: dynamic type error, static type warning
+    var x = a is I; // //# 03: dynamic type error, static type warning
 
     // In both production and checked modes, A<String> is a subtype of J.
-    Expect.isTrue(a is J); // /// 04: static type warning
+    Expect.isTrue(a is J); // //# 04: static type warning
 
     // In both production and checked modes, A<String> is not a subtype of K.
     // However, while unsuccessfully trying to prove that A<String> is a K,
     // a malformed type is encountered in checked mode, resulting in a dynamic
     // type error.
-    Expect.isTrue(a is !K); // /// 05: dynamic type error, static type warning
+    Expect.isTrue(a is !K); // //# 05: dynamic type error, static type warning
   }
 
   a = new A<int>();
 
   {
     I i = a;
     J j = a;
-    K k = a; // /// 06: dynamic type error, static type warning
+    K k = a; // //# 06: dynamic type error, static type warning
 
     // In both production and checked modes, A<int> is a subtype of I.
     Expect.isTrue(a is I);
 
     // In both production and checked modes, A<int> is a subtype of J.
     Expect.isTrue(a is J);
 
     // In both production and checked modes, A<int> is not a subtype of K.
     Expect.isTrue(a is !K);
   }
 }