Move kernel baseline tests to front_end.

pkg/kernel/testcases/input/external.dart

Index: pkg/kernel/testcases/input/external.dart
diff --git a/pkg/kernel/testcases/input/external.dart b/pkg/kernel/testcases/input/external.dart
deleted file mode 100644
index 54ce8a74005d829d64550a631d99c3bb95f1eb19..0000000000000000000000000000000000000000
--- a/pkg/kernel/testcases/input/external.dart
+++ /dev/null
@@ -1,18 +0,0 @@
-// 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 'dart:isolate';
-
-var subscription;
-
-void onData(x) {
-  print(x);
-  subscription.cancel();
-}
-
-main() {
-  var string = new String.fromCharCode(65); // External string factory.
-  var port = new ReceivePort(); // External factory.
-  subscription = port.listen(onData); // Dynamic call on external instance.
-  port.sendPort.send(string);
-}