Delete stray comment in tests.

tests/language/vm/string_polymorphic_test.dart

Index: tests/language/vm/string_polymorphic_test.dart
diff --git a/tests/language/vm/string_polymorphic_test.dart b/tests/language/vm/string_polymorphic_test.dart
index 72eac28b3a5939c6cfe617f76dd8fa95e6922f91..8e0dc220ddb962f6bb8010af4fa053c5d8a87a69 100644
--- a/tests/language/vm/string_polymorphic_test.dart
+++ b/tests/language/vm/string_polymorphic_test.dart
@@ -1,7 +1,6 @@
 // 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.
-// Tests that the VM does not crash on weird corner cases of class Math.
 // VMOptions=--optimization_counter_threshold=10 --no-background_compilation
 
 import 'package:expect/expect.dart';