Initial support for managing partial results from plugins

pkg/analysis_server/test/src/plugin/test_all.dart

-// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2017, 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 test.src;
-
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
-import 'utilities/test_all.dart' as utilities_all;
+import 'result_collector_test.dart' as result_collector_test;
 
-/**
- * Utility for manually running all tests.
- */
 main() {
   defineReflectiveSuite(() {
-    utilities_all.main();
-  }, name: 'analysis_server');
+    result_collector_test.main();
+  });
 }