No need to clear IOStream.close_callback in MotorSocket.close()
No need to clear IOStream.close_callback in MotorSocket.close()

The check, above, for "child_gr.dead" makes it redundant (and slightly incorrect) to clear the close callback in MotorSocket.close()

asvetlov/motor,wujuguang/motor,wujuguang/motor,mongodb/motor,mongodb/motor