Port remaining Sky tests to the new world

sky/tests/services/network.dart

-#!mojo mojo:sky_viewer
-<sky>
-<script>
 import 'dart:async';
 import 'dart:typed_data';
 import "dart:sky.internals" as internals;
 
 import 'package:mojo/bindings.dart';
 import 'package:mojo/core.dart';
 import 'package:mojom/mojo/network_service.mojom.dart';
 import 'package:mojom/mojo/url_request.mojom.dart';
 import 'package:mojom/mojo/url_loader.mojom.dart';
 
@@ skipping 24 matching lines @@
   print("read ${bodyData.lengthInBytes} bytes");
 
   return new String.fromCharCodes(new Uint8List.view(bodyData.buffer));
 }
 
 main() async {
   var url = "http://127.0.0.1:8000/sky/tests/services/resources/pass.txt";
   var result = await run(url);
   internals.notifyTestComplete(result);
 }
-</script>
-</sky>