Move long-running test to its own test-file.

tests/compiler/dart2js/serialization/compilation0_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.
 
 library dart2js.serialization.compilation1_test;
 
 import 'compilation_test_helper.dart' as test;
 import 'test_data.dart';
 
 main() {
-  test.main(['0', '${TESTS.length ~/ 4}']);
+  test.main(['0', '0']);
 }