[O] org-clock-save.el state unwanted Resume clock prompt

[Jeff Kowalczyk]

When opening any org mode files or using M-x org-mode on a
buffer, I get the following prompt:

: Resume clock (bsmith re: status update) (y or n)  n

Which refers to a specific heading in one specific org file, used
all day most days.

: ** DONE bsmith re: status update
:    CLOSED: [2013-08-06 Tue 13:12]
:    :LOGBOOK:
:    CLOCK: [2013-08-06 Tue 12:53]--[2013-08-06 Tue 13:12] =>  0:19
:    :END:

The cause of the prompt is easily found (org-clock-save.el,
source wrapped):

: ;; org-persist.el - myhost at <2013-08-06 Tue 13:42>
: (setq resume-clock '("/home/jtk/org/upwind.org" . 2049565))
: 
: (setq stored-clock-history 
: '(("/home/myuser/org/acme.org" . 2044203)
:   ("/home/myuser/org/acme.org" . 2044243)
:   ("/home/myuser/org/acme.org" . 2046954)
:   ("/home/myuser/org/acme.org" . 2049576)
:   ("/home/myuser/org/acme.org" . 2049494)))

The above headline corresponds to the last position character
mark, 2049494.

My questions are:

- What's different about that heading that it isn't closed?

- Is there another lisp source of clock insinuate data besides
  org-persist.el?

- What lisp data edit operation would safely clear the
  open clock status?

On a few occasions I've deleted org-clock-save.el to clear
the problem, and had a recurrence on a different heading some
weeks later. There could be some behavior related to running
clocks when emacs daemon stops abruptly on system or X
shutdown.

Thanks,
Jeff