Task.retry must also forward links (e.g. for chains). Closes celery/django-celery#157

celery/app/task.py

@@ -541,7 +541,9 @@ class Task(object):
         options.update({'retries': request.retries + 1,
                         'task_id': request.id,
                         'countdown': countdown,
-                        'eta': eta})
+                        'eta': eta,
+                        'link': request.callbacks,
+                        'link_error': request.errbacks})
 
         if max_retries is not None and options['retries'] > max_retries:
             if exc:

celery/worker/job.py

@@ -60,7 +60,6 @@ class Request(object):
     """A request for task execution."""
     __slots__ = ('app', 'name', 'id', 'args', 'kwargs',
                  'on_ack', 'delivery_info', 'hostname',
-                 'callbacks', 'errbacks',
                  'eventer', 'connection_errors',
                  'task', 'eta', 'expires',
                  'request_dict', 'acknowledged', 'success_msg',