bug#5998: 23.1.96; Breadcrumbs defeat C-u 1 C-v in Info

[Drew Adams]

>  emacs -Q
>  C-u C-h i /path/to/emacs/info/emacs RET
>  g Narrowing RET
>  C-u 1 C-v
> 
> Note that the display does not scroll by one line.

And it is a regression: the problem does not exist in
GNU Emacs 23.1.95.1 (i386-mingw-nt5.1.2600)
 of 2010-04-03 on G41R2F1