bug#7206: 24.0.50; Bugs with minibuffer completion

[Tim Van Holder <tim.vanholder@gmail.com>]

Current bzr (r101947) has 2 issues with completion in the minibuffer:

Recipe:

$ emacs -Q
  C-x C-f

Issue #1:

  Enter anything that has a non-unique completion (or don't enter
  anything at all after ther default directory name prompt), and press
  [tab]. Instead of getting the "[Complete, but not unique]" prompt, you
  get an error instead:
    minibuffer-completion-help: Wrong type argument: listp, 0
  (the integer varies).
  This also happens with non-path completions (e.g. C-h f).

Issue #2:

  Put point inside the path prompt and delete the trailing part of a
  path component, taking care to still keep a unique prefix to avoid
  hitting issue #1. Pressing [tab] to re-complete the path component
  works fine, but point "jumps back" several positions. This does not
  happen for completions at the end of the path, nor does it seem to
  heppen for non-path completions (at least for [C-h f] the problem does
  not seem to exist).


In GNU Emacs 24.0.50.1 (i686-pc-linux-gnu, GTK+ Version 2.8.20)
 of 2010-10-13 on leeloo
Windowing system distributor `The Cygwin/X Project', version 11.0.10503000
configured using `configure  '--with-x''