Bugfix amarok crash

[Ralf Engels]

On So, 2010-08-15 at 14:36 +0200, Ralf Engels wrote:
> ...
> >     * This patch is going to make "remove tracks" agonizingly slow in
> >       large playlists. O(N*M).
> > 
> 
> I haven't thought about this but O(N*M) only holds if you clear the
> whole playlist.
> For deleting a single file with O(N) that should be fine.
> 

Of cause I wrote something stupid here.

What I meant was that the evil case with O(N^2) only happens with a full
playlist clear.

Ralf