dart2js cps: Bugfix in operator specialization.

tests/language/string_no_operator_test.dart

+// Copyright (c) 2015, 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';
+
+main() {
+        var x = "x";

[karlklose, 2015/07/07 12:48:00]

That's a lot of spaces.

+        var y = "y";
+        Expect.throws(() => x < y);
+        Expect.throws(() => x <= y);
+        Expect.throws(() => x > y);
+        Expect.throws(() => x >= y);
+        Expect.throws(() => x - y);
+        Expect.throws(() => x * y);
+        Expect.throws(() => x / y);
+        Expect.throws(() => x ~/ y);
+        Expect.throws(() => x % y);
+        Expect.throws(() => x >> y);
+        Expect.throws(() => x << y);
+        Expect.throws(() => x & y);
+        Expect.throws(() => x | y);
+        Expect.throws(() => x ^ y);
+        Expect.throws(() => -x);
+        Expect.throws(() => ~x);
+}