Add a hack to globally register a platform plugin.

lib/src/runner/loader.dart

 // Copyright (c) 2015, 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:async';
 import 'dart:io';
 
 import 'package:analyzer/analyzer.dart' hide Configuration;
 import 'package:async/async.dart';
 import 'package:path/path.dart' as p;
 
 import '../backend/group.dart';
 import '../backend/metadata.dart';
 import '../backend/test_platform.dart';
 import '../util/io.dart';
 import '../utils.dart';
 import 'browser/platform.dart';
 import 'configuration.dart';
 import 'load_exception.dart';
 import 'load_suite.dart';
 import 'parse_metadata.dart';
 import 'plugin/environment.dart';
+import 'plugin/hack_register_platform.dart';
 import 'plugin/platform.dart';
 import 'runner_suite.dart';
 import 'vm/platform.dart';
 
 /// A class for finding test files and loading them into a runnable form.
 class Loader {
   /// The test runner configuration.
   final Configuration _config;
 
   /// The root directory that will be served for browser tests.
@@ skipping 19 matching lines @@
     registerPlatformPlugin([TestPlatform.vm], () => new VMPlatform(_config));
     registerPlatformPlugin([
       TestPlatform.dartium,
       TestPlatform.contentShell,
       TestPlatform.chrome,
       TestPlatform.phantomJS,
       TestPlatform.firefox,
       TestPlatform.safari,
       TestPlatform.internetExplorer
     ], () => BrowserPlatform.start(_config, root: root));
+
+    platformCallbacks.forEach((platform, plugin) {
+      registerPlatformPlugin([platform], plugin);
+    });
   }
 
   /// Registers a [PlatformPlugin] for [platforms].
   ///
   /// When the runner first requests that a suite be loaded for one of the given
   /// platforms, this will call [getPlugin] to load the platform plugin. It may
   /// return either a [PlatformPlugin] or a [Future<PlatformPlugin>]. That
   /// plugin is then preserved and used to load all suites for all matching
   /// platforms.
   ///
@@ skipping 104 matching lines @@
       })),
       Future.wait(_suites.map((suite) => suite.close()))
     ]);
 
     _platformPlugins.clear();
     _platformCallbacks.clear();
     _suites.clear();
   });
   final _closeMemo = new AsyncMemoizer();
 }