'Same as GetNotificationsByPriority but for all shards.
Used by worker_test to cover all shards with a single worker.
Args:
queue: usually rdfvalue.RDFURN("aff4:/W")
Returns:
dict of notifications objects keyed by priority.'

def GetNotificationsByPriorityForAllShards(self, queue):

    output_dict = {}
    for queue_shard in self.GetAllNotificationShards(queue):
        self._GetUnsortedNotifications(queue_shard, notifications_by_session_id=output_dict)
    return self._SortByPriority(output_dict.values(), queue)
