Pass actual TestPlatform and OperatingSystem values to Suite.

lib/src/runner/browser/server.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 test.runner.browser.server;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
@@ skipping 279 matching lines @@
       suiteUrl = url.resolveUri(p.toUri(
           p.withoutExtension(p.relative(path, from: _root)) + ".html"));
     }
 
     if (_closed) return null;
 
     // TODO(nweiz): Don't start the browser until all the suites are compiled.
     var browserManager = await _browserManagerFor(browser);
     if (_closed) return null;
 
-    var suite;
     if (browserManager != null) {
-      suite = await browserManager.loadSuite(path, suiteUrl, metadata,
+      var suite = await browserManager.loadSuite(path, suiteUrl, metadata,
           mapper: browser.isJS ? _mappers[path] : null);
       if (_closed) return null;
+      if (suite != null) return suite;
     }
 
-    if (suite != null) return suite.change(platform: browser.name);
-
     // If the browser manager fails to load a suite and the server isn't
     // closed, it's probably because the browser failed. We emit the failure
     // here to ensure that it gets surfaced.
     return _browsers[browser].onExit;
   }
 
   /// Loads a test suite at [path] from the `pub serve` URL [jsUrl].
   ///
   /// This ensures that only one suite is loaded at a time, and that any errors
   /// are exposed as [LoadException]s.
@@ skipping 162 matching lines @@
       await Future.wait(futures);
 
       if (_pubServeUrl == null) {
         new Directory(_compiledDir).deleteSync(recursive: true);
       } else {
         _http.close();
       }
     });
   }
 }