Add PositionOptions type to registry.

lib/dom/dom.dart

Index: lib/dom/dom.dart
diff --git a/lib/dom/dom.dart b/lib/dom/dom.dart
index 04509dfd576851c9ace0d43bc997809ba5f0ef2d..2e21adea76ef468e4a80a0d81e417857bb04b8ed 100644
--- a/lib/dom/dom.dart
+++ b/lib/dom/dom.dart
@@ -3142,9 +3142,9 @@ interface Geolocation {
 
   void clearWatch(int watchId);
 
-  void getCurrentPosition(PositionCallback successCallback, [PositionErrorCallback errorCallback]);
+  void getCurrentPosition(PositionCallback successCallback, [PositionErrorCallback errorCallback, Object options]);
 
-  int watchPosition(PositionCallback successCallback, [PositionErrorCallback errorCallback]);
+  int watchPosition(PositionCallback successCallback, [PositionErrorCallback errorCallback, Object options]);
 }
 // 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