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

tests/kernel/unsorted/as_is_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.
-
-// Tests of class literals, is, and as expressions.
-
-import 'expect.dart';
-
-class C {}
-
-class D extends C {}
-
-test0() => C;
-test1() => D;
-
-main() {
-  var c = new C();
-  var d = new D();
-  Expect.isTrue(test0() == C);
-  Expect.isTrue(test1() == D);
-  Expect.isTrue(c is C);
-  Expect.isTrue(c is! D);
-  Expect.isTrue(d is C);
-  Expect.isTrue(d is D);
-  Expect.isTrue(c as C == c);
-  Expect.isTrue(d as C == d);
-  Expect.isTrue(d as D == d);
-}