Increase the default test timeout for scheduled tests on Windows.

pkg/scheduled_test/test/scheduled_server_test.dart

Index: pkg/scheduled_test/test/scheduled_server_test.dart
diff --git a/pkg/scheduled_test/test/scheduled_server_test.dart b/pkg/scheduled_test/test/scheduled_server_test.dart
index 19135e0c834b88c2f4a3086cc2656c5b41a3fedb..b34765c6f22e3754b787db3802e7d552bcf767d8 100644
--- a/pkg/scheduled_test/test/scheduled_server_test.dart
+++ b/pkg/scheduled_test/test/scheduled_server_test.dart
@@ -16,6 +16,12 @@ import 'metatest.dart';
 import 'utils.dart';
 
 void main() {
+  metaSetUp(() {
+    // The windows bots are very slow, so we increase the default timeout.
+    if (Platform.operatingSystem != "windows") return;
+    currentSchedule.timeout = new Duration(seconds: 10);
+  });
+
   expectTestsPass("a server with no handlers does nothing", () {
     test('test', () => new ScheduledServer());
   });