Use identifiers in OperatingSystem.find.

lib/src/runner/plugin/platform_helpers.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.
 
 import 'dart:async';
 
 import 'package:stack_trace/stack_trace.dart';
 import 'package:stream_channel/stream_channel.dart';
 
 import '../../backend/group.dart';
@@ skipping 23 matching lines @@
     TestPlatform platform, Metadata metadata, Environment environment,
     StreamChannel channel, {StackTrace mapTrace(StackTrace trace)}) async {
   if (mapTrace == null) mapTrace = (trace) => trace;
 
   var disconnector = new Disconnector();
   var suiteChannel = new MultiChannel(channel.transform(disconnector));
 
   suiteChannel.sink.add({
     'platform': platform.identifier,
     'metadata': metadata.serialize(),
-    'os': platform == TestPlatform.vm ? currentOS.name : null
+    'os': platform == TestPlatform.vm ? currentOS.identifier : null
   });
 
   var completer = new Completer();
 
   handleError(error, stackTrace) {
     disconnector.disconnect();
 
     if (completer.isCompleted) {
       // If we've already provided a controller, send the error to the
       // LoadSuite. This will cause the virtual load test to fail, which will
@@ skipping 71 matching lines @@
   ///
   /// Returns `null` if [test] is `null`.
   Test _deserializeTest(Map test) {
     if (test == null) return null;
 
     var metadata = new Metadata.deserialize(test['metadata']);
     var testChannel = _channel.virtualChannel(test['channel']);
     return new RunnerTest(test['name'], metadata, testChannel, _mapTrace);
   }
 }