VM: Fix bug in canonicalization of identical in the optimizing compiler.

tests/language/vm/optimized_identical_test.dart

Index: tests/language/vm/optimized_identical_test.dart
===================================================================
--- tests/language/vm/optimized_identical_test.dart	(revision 0)
+++ tests/language/vm/optimized_identical_test.dart	(revision 0)
@@ -0,0 +1,25 @@
+// Copyright (c) 2013, 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.
+// Test various optimizations and deoptimizations of optimizing compiler..
+// VMOptions=--optimization-counter-threshold=10 --no-constant-propagation
+
+import "package:expect/expect.dart";
+
+// Test canonicalization of identical with double input.
+// Constant propagation is disabled so that canonicalization is run
+// one time less than usual.
+
+test(a) {
+  var dbl = a + 1.0;
+  if (!identical(dbl, true)) {
+    return "ok"; 
+  }
+  throw "fail";
+}
+
+main() {
+  for (var i = 0; i < 20; i++) test(0);
+  Expect.equals("ok", test(0));
+}
+