Generated front_end/testcases/inference test files from Analyzer tests.

pkg/front_end/testcases/inference/downwards_inference_for_each.dart

+// Copyright (c) 2017, 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.
+
+/*@testedFeatures=inference*/
+library test;
+
+import 'dart:async';
+
+abstract class MyStream<T> extends Stream<T> {
+  factory MyStream() => null;
+}
+
+Future main() async {
+  for (int /*@promotedType=none*/ x in /*@typeArgs=int*/ [1, 2, 3]) {}
+  await for (int /*@promotedType=none*/ x
+      in /*@typeArgs=int*/ new MyStream()) {}
+}