Fix warnings_checker.dart handling of multitests

tests/language/identical_const_test.dart

 // Copyright (c) 2014, 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';
 
 f() {}
 const g = 1;
 
 const identical_ff = identical(f, f);
 const identical_fg = identical(f, g);
 const identical_gf = identical(g, f);
 const identical_gg = identical(g, g);
 
 // Verify proper compile time computation of identical()
 const a = const {
-  identical_ff: 0, /// 01: static type warning
-  identical_gg: 0, /// 02: static type warning
+  identical_ff: 0, //# 01: static type warning
+  identical_gg: 0, //# 02: static type warning
   true: 0 };
 
 const b = const {
-  identical_fg: 0, /// 03: static type warning
-  identical_gf: 0, /// 04: static type warning
+  identical_fg: 0, //# 03: static type warning
+  identical_gf: 0, //# 04: static type warning
   false: 0 };
 
 use(x) => x;
 
 main() {
   use(a);
   use(b);
 
   // Verify proper run time computation of identical()
-  Expect.isTrue(identical_ff); /// 05: ok
-  Expect.isTrue(identical_gg); /// 06: ok
-  Expect.isFalse(identical_fg); /// 07: ok
-  Expect.isFalse(identical_gf); /// 08: ok
+  Expect.isTrue(identical_ff); //# 05: ok
+  Expect.isTrue(identical_gg); //# 06: ok
+  Expect.isFalse(identical_fg); //# 07: ok
+  Expect.isFalse(identical_gf); //# 08: ok
 }