[Freeciv-Dev] Wrong mouse cursor after window resize (PR#1041)

[sigra@xxxxxxx]

Name: Erik Sigra
Version: CVS
Client: GTK

1. Open a city dialog (or use the main client window (or any other window)).
2. Increase the size of the window so that it can be decreased (the size
   should be larger than the minimum size).
3. Resize again to make the window smaller by dragging a border inwards. But
   don't stop the mouse to release the button, keep it moving towards the
   center of the dialog. If you are fast, the resize mouse cursor will remain.
   So in the dialog you get a <-> mouse cursor.