Move kernel baseline tests to front_end.

pkg/front_end/test/fasta/cascade.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 file.
-
-main() {
-  var list = [1]
-      ..add(2)
-      ..add(3)
-      ..addAll([4, 5]);
-  print(list);
-
-  list
-      ..add(2)
-      ..length
-      ..length = 0;
-  print(list);
-
-  list
-      ..add(2)
-      ..[0]
-      ..[0] = 87;
-
-  print(list);
-
-  list = [[1]]
-      ..first.last.toString()
-      ..first[0].toString()
-      ..[0].last.toString();
-
-  print(list);
-}