tasks_list_sync
Description:
public bool tasks_list_sync (string tasklist_id, GDataQuery? query, GDataObjectCallback? cb, Cancellable? cancellable = null) throws Error
  
  Lists all tasks in the task list tasklist_id, calling the cb for each of them.
Parameters:
| this | 
           an GDataSession  | 
      
| tasklist_id | 
           id of a task list  | 
      
| query | 
           an GDataQuery to limit returned tasks, or   | 
      
| cb | 
           an GDataObjectCallback to call for each found task  | 
      
| cancellable | 
           optional Cancellable object, or   | 
      
| user_data | 
           user data passed to the   | 
      
Returns:
| 
           whether succeeded  |