Move kernel baseline tests to front_end.

pkg/front_end/testcases/super_rasta_copy.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.
 
 // TODO(ahe): This is a copy of [rasta/super.dart] without the `n`
 // property. Remove this once fasta can handle all of the original file.
 
 class A {
   var a;
   var b;
@@ skipping 227 matching lines @@
 }
 
 main() {
   try {
     new C().test();
   } on NoSuchMethodError {
     return; // Test passed.
   }
   throw "Test failed";
 }