Fix invalid SSA graph generated by dart2js by using the savedLocals in a do/while (the ones before …

tests/language/do_while4_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 crash in the presence of
+// do/while, break and a local variable declared after the break.
+
+import "package:expect/expect.dart";
+
+var a = false;
+main() {
+  do {
+    if (!a) break;
+    var c = main();
+    a = true;
+  } while (true);
+  Expect.isFalse(a);
+}