Increase the default test timeout for scheduled tests on Windows.

pkg/scheduled_test/test/scheduled_process_test.dart

Index: pkg/scheduled_test/test/scheduled_process_test.dart
diff --git a/pkg/scheduled_test/test/scheduled_process_test.dart b/pkg/scheduled_test/test/scheduled_process_test.dart
index 974294737f543ec419a885ae34df0d48acd584da..4b89da154bcfb0096aaa9b937ad6bcea15e47352 100644
--- a/pkg/scheduled_test/test/scheduled_process_test.dart
+++ b/pkg/scheduled_test/test/scheduled_process_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 process must have kill() or shouldExit() called", () {
     var errors;
     test('test 1', () {