Make browser tests all run from a server instead of the local filesystem.

sdk/lib/html/dart2js/html_dart2js.dart

 library html;
 
 import 'dart:async';
 import 'dart:collection';
 import 'dart:html_common';
 import 'dart:indexed_db';
 import 'dart:isolate';
 import 'dart:json' as json;
 import 'dart:math';
 import 'dart:svg' as svg;
@@ skipping 25640 matching lines @@
 };
 // Copyright (c) 2012, 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.
 
 
 class _HttpRequestUtils {
 
   // Helper for factory HttpRequest.get
   static HttpRequest get(String url,
-                            onSuccess(HttpRequest request),
+                            onComplete(HttpRequest request),
                             bool withCredentials) {
     final request = new HttpRequest();
     request.open('GET', url, true);
 
     request.withCredentials = withCredentials;
 
-    // Status 0 is for local XHR request.
     request.on.readyStateChange.add((e) {
-      if (request.readyState == HttpRequest.DONE &&
-          (request.status == 200 || request.status == 0)) {
-        onSuccess(request);
+      if (request.readyState == HttpRequest.DONE) {
+        onComplete(request);
       }
     });
 
     request.send();
 
     return request;
   }
 }
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
@@ skipping 1287 matching lines @@
       _position = nextPosition;
       return true;
     }
     _current = null;
     _position = _array.length;
     return false;
   }
 
   T get current => _current;
 }