Created attachment 154826 [details] [review]
Patch by Lars Kruse to fix drag-and-drop behavior

Original report: http://bugs.debian.org/562005 by Lars Kruse
Note that item 3 is bug#608221.

naming conventions for the following description:
- "item pane": right half of the window
- "menu pane": left part of the window

various GUI actions of alacarte don't work as expected:

1) drag and drop of an item from the item pane "into" a menu item of the item
pane

I expect the dragged item to be moved into the selected target menu, but the
item just gets moved to the position after the target.
The same operation works as expected, if the destination is on the "menu pane".


2) moving a separator item from the item pane "into" a menu item of the "menu
pane"

I expect, that this removes the dragged separator from the original menu and
creates a new separator in the destination. The GUI feedback also indicates
this: the separator disappears.
But the separator is not moved at all: clicking on the original menu (for
refresh) causes the separator to appear again. The destination menu does not
contain a new separator.


3) dragging an item from the item pane to another position in the item pane
(between two other items)

This works as expected, if the destination is _above_ the current position of
the dragged item. But if it is below, then the item gets moved one position
further down, than expected.