bug#5846: 23.1.95.1 problems with mercurial commands in *VC Annotate* buffer on Windows

[Chong Yidong]

> In GNU Emacs 23.1.95.1 (i386-mingw-nt5.1.2600)
>
> Using Mercurial from TortoiseHg 0.9, which contains Mercurial-1.4,
> Python-2.5.4, PyGTK-2.12.1, GTK-2.16.1
>
> Start emacs with "c:\emacs\23.1.95\bin\emacs -Q"
> Open a file from a mercurial repository
> Type "C-x v g" to annotate the file
>
> In the *VC Annotate* buffer:
> 1) Type "l" (vc-annotate-show-log-revision-at-line)
>    The Hg command runs, but the *vc-change-log* buffer is empty
>
> 2) Type "f" (vc-annotate-find-revision-at-line)
>    Emacs displays a message "Cannot open load file: vc-nil"

It looks like this is the same bug as the one just fixed in

  http://debbugs.gnu.org/cgi/bugreport.cgi?bug=5960

You can find the patch there, and it will be included in the next
pretest.

Thanks for the bug report.