Do not evaluate inlined field initializations twice in a redirecting constructor.

tests/language/evaluation_redirecting_constructor_test.dart

Index: tests/language/evaluation_redirecting_constructor_test.dart
===================================================================
--- tests/language/evaluation_redirecting_constructor_test.dart	(revision 0)
+++ tests/language/evaluation_redirecting_constructor_test.dart	(revision 0)
@@ -0,0 +1,24 @@
+// 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.
+
+import "package:expect/expect.dart";
+
+int counter = 0;
+
+class Bar {
+  Bar() {
+    counter++;
+  }
+}
+
+class A {
+  var _bar = new Bar();
+  A() : this._();
+  A._() {() => 42;}
+}
+
+main() {
+  new A();
+  Expect.equals(1, counter);
+}