def _AbandonQueuedTasks(self):
    """Marks queued tasks abandoned.

    This method does not lock the manager and should be called by a method
    holding the manager lock.
    """
    # Abandon all tasks after they're identified so as not to modify the
    # dict while iterating over it.
    tasks_to_abandon = []
    for task_identifier, task in iter(self._tasks_queued.items()):
      logger.debug('Abandoned queued task: {0:s}.'.format(task_identifier))
      tasks_to_abandon.append((task_identifier, task))

    for task_identifier, task in tasks_to_abandon:
      self._tasks_abandoned[task_identifier] = task
      del self._tasks_queued[task_identifier]
Marks queued tasks abandoned.

    This method does not lock the manager and should be called by a method
    holding the manager lock.