Merge kernel closure conversion into the Dart SDK

pkg/kernel/testcases/closures/closures.dart

Index: pkg/kernel/testcases/closures/closures.dart
diff --git a/pkg/kernel/testcases/closures/closures.dart b/pkg/kernel/testcases/closures/closures.dart
new file mode 100644
index 0000000000000000000000000000000000000000..545ad551e9dc493eff917144a43cb83c15e62a9f
--- /dev/null
+++ b/pkg/kernel/testcases/closures/closures.dart
@@ -0,0 +1,14 @@
+// Copyright (c) 2016, 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.md file.
+
+var f;
+
+foo() {
+  print(f(0));
+}
+
+main(arguments) {
+  f = (x) => arguments[x];
+  foo();
+}