Merge kernel closure conversion into the Dart SDK

pkg/kernel/testcases/closures/non_void_context.dart

Index: pkg/kernel/testcases/closures/non_void_context.dart
diff --git a/pkg/kernel/testcases/closures/non_void_context.dart b/pkg/kernel/testcases/closures/non_void_context.dart
new file mode 100644
index 0000000000000000000000000000000000000000..0987ab5f218c571581e600be24832d6fba629ce8
--- /dev/null
+++ b/pkg/kernel/testcases/closures/non_void_context.dart
@@ -0,0 +1,28 @@
+// 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 v;
+
+main(arguments) {
+  var w;
+  ((x) => v = w = x)(87);
+  if (v != 87) {
+    throw "Unexpected value in v: $v";
+  }
+  if (w != 87) {
+    throw "Unexpected value in w: $w";
+  }
+  v = true;
+  (() {
+    for (; w = v;) {
+      v = false;
+    }
+  })();
+  if (v != false) {
+    throw "Unexpected value in v: $v";
+  }
+  if (w != false) {
+    throw "Unexpected value in w: $w";
+  }
+}