Move kernel baseline tests to front_end.

pkg/front_end/testcases/rasta/unresolved_for_in.dart

 // 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.
 
 import 'dart:collection' as collection;
 
 typedef void VoidFunction();
 
 class Fisk {
   it1(x) {
@@ skipping 26 matching lines @@
   for (collection in arguments) {
     print(collection);
   }
   for (VoidFunction in arguments) {
     print(VoidFunction);
   }
   for (1 in arguments) {
     print(key);
   }
 }