bug#4131: Description how to reproduce the bug

[Carsten Dominik <dominik@uva.nl>]

Hi, somehow my description how to reproduce the bug seems to have not  
made it with the report.

Here it is:

Emacs can be repeatedly crashed by using a combination of `outline-mode'
and line-prefix text properties.  The crash happens when a call to
`(hide-sublevels 1)' makes everything currently visible in an Emacs  
window
invisible, while the text in the window has line-prefix text properties.

Here is a way to reproduce this bug:

Put the following text into a file and open the file in Emacs:


----------------------8x------------8x----------------8x
    -*- mode: outline -*-

* my test
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(add-text-properties (point-min) (point-max) '(line-prefix "  "))
(hide-sublevels 1)
----------------------8x------------8x----------------8x


The number of lines must be large enough so that scrolling to the end of
the buffer will move the outline headline "my test" out of view.

Move to the end of the file and evaluate the two lisp forms, first  
adding the text properties and then hiding everything except top level.



- Carsten