Add a testOn parameter to test() and group().

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.
 
 library unittest.runner.loader;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
 
@@ skipping 85 matching lines @@
       throw new LoadException(path, error);
     }
 
     return Future.wait(_platforms.map((platform) {
       return new Future.sync(() {
         if (!metadata.testOn.evaluate(platform, os: currentOS)) return null;
 
         if (platform == TestPlatform.chrome) return _loadBrowserFile(path);
         assert(platform == TestPlatform.vm);
         return _loadVmFile(path);
-      }).then((suite) =>
-          suite == null ? null : suite.change(metadata: metadata));
+      }).then((suite) {
+        if (suite == null) return null;
+        return suite.change(metadata: metadata).filter(platform, os: currentOS);
+      });
     })).then((suites) => suites.where((suite) => suite != null).toList());
   }
 
   /// Load the test suite at [path] in a browser.
   Future<Suite> _loadBrowserFile(String path) =>
       _browserServer.then((browserServer) => browserServer.loadSuite(path));
 
   /// Load the test suite at [path] in VM isolate.
   Future<Suite> _loadVmFile(String path) {
     var packageRoot = packageRootFor(path, _packageRoot);
@@ skipping 20 matching lines @@
       if (response["type"] == "loadException") {
         return new Future.error(new LoadException(path, response["message"]));
       } else if (response["type"] == "error") {
         var asyncError = RemoteException.deserialize(response["error"]);
         return new Future.error(
             new LoadException(path, asyncError.error),
             asyncError.stackTrace);
       }
 
       return new Suite(response["tests"].map((test) {
-        return new IsolateTest(test['name'], test['sendPort']);
+        var metadata = new Metadata.deserialize(test['metadata']);
+        return new IsolateTest(test['name'], metadata, test['sendPort']);
       }), path: path, platform: "VM");
     });
   }
 
   /// Closes the loader and releases all resources allocated by it.
   Future close() {
     for (var isolate in _isolates) {
       isolate.kill();
     }
     _isolates.clear();
 
     if (_browserServerCompleter == null) return new Future.value();
     return _browserServer.then((browserServer) => browserServer.close());
   }
 }