docs: private void failTask(final ExecutionAttemptID executionAttemptID, final Throwable cause) {
  		final Task task = taskSlotTable.getTask(executionAttemptID);
  
  		if (task != null) {
  			try {
  				task.failExternally(cause);
  			} catch (Throwable t) {
  				log.error("Could not fail task {}.", executionAttemptID, t);
  			}
  		} else {
  			log.debug("Cannot find task to fail for execution {}.", executionAttemptID);
  		}
  	}