Calls the get_object_sync method on the given backend.
| this |
An ECalBackendSync object. |
| cal |
An EDataCal object. |
| cancellable |
a Cancellable for the operation |
| uid |
UID of the object to get. |
| rid |
Recurrence ID of the specific instance to get, or null if getting the master object. |
| calobj |
Placeholder for returned object. |