Revert "Reland "Merge more Kernel infrastructure from kernel_sdk SDK fork.""

tests/kernel/unsorted/super_mixin_test.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.
-
-import 'expect.dart';
-
-class Base {
-  var field;
-
-  method(x) {
-    print(x);
-    return x;
-  }
-
-  set setter(x) {
-    print(x);
-    field = x;
-  }
-}
-
-class Mixin {
-  method(x) {
-    return super.method(x + 'Mixin');
-  }
-
-  set setter(x) {
-    super.setter = x + 'Mixin';
-  }
-}
-
-class Sub extends Base with Mixin {
-}
-
-main() {
-  var object = new Sub();
-  Expect.isTrue(object.method('x') == 'xMixin');
-  object.setter = 'y';
-  Expect.isTrue(object.field == 'yMixin');
-}