Fix position error when clocking in while buffer is narrowed

Fix position error when clocking in while buffer is narrowed

Bernt Hansen writes:

> If you narrow to subtree when there is a following task the narrowed
> buffer has a blank line at the end.  If you are on this line and
> clock-in it starts the clock for the _following_ task (outside the
> narrowed subtree) and not the task you are looking at.
>
> I stumbled across this today because the following task was already
> over the estimated limit when I clocked it in - which triggered my
> alarm sound.
>
> ,----[ test.org ]
> | #+STARTUP:
> | * TODO One
> | * TODO Two
> `----
>
> ,----[ minimal.emacs ]
> | (add-to-list 'load-path (expand-file-name "~/git/org-mode/lisp"))
> | (add-to-list 'auto-mode-alist
> |              '("\\.\\(org\\|org_archive\\|txt\\)$" . org-mode))
> | (require 'org-install)
> |
> | (global-set-key "\C-cl" 'org-store-link)
> | (global-set-key "\C-ca" 'org-agenda)
> | (global-set-key "\C-cb" 'org-iswitchb)
> `----
>
> Key sequence to reproduce:
>
> $ emacs -q -l minimal.emacs test.org
>
> | Key                           | Notes                         |
> |-------------------------------+-------------------------------|
> | C-n                           | Go to first task '* TODO One' |
> | M-x org-narrow-to-subtree RET | Narrow to subtree             |
> | C-n                           | Move to last blank line       |
> | C-c C-x C-i                   | Clock in (next) task          |
> |-------------------------------+-------------------------------|
>
> -Bernt
>
> Emacs  : GNU Emacs 22.2.1 (i486-pc-linux-gnu, GTK+ Version 2.12.11)
> of 2008-11-09 on raven, modified by Debian
> Package: Org-mode version 6.31trans (release_6.31.8.g7485)