Fix a bug where we would emit:

tests/language/for_inlining_test.dart

+// 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.
+
+// Regression test for dart2js that used to emit an invalid JS
+// variable declaration initializer in a for initializer.
+
+import "package:expect/expect.dart";
+
+var global;
+
+inlineMe() {
+  global = 42;
+  return 54;
+}
+
+main() {
+  for (var t = inlineMe(); t < 42; t++) {}
+  Expect.equals(42, global);
+}