KListView breakage in HEAD

[Chris Lee]

This seems to be due to a bug in qt-copy.

QListViewItem has a 'dragEnabled()' function which will return true or 
false on an item-by-item basis. The problem with this is that on a 
clickEvent, Qt will check the currently-selected list item to see if 
it's draggable, and if not, deselect the other selected list items.

KListView::setDragEnabled doesn't call QLVI::setDragEnabled() on all of 
its items when it's called, leading to the problem.

This breaks a few things. Notably, dragging of multiple files from Konq, 
dragging of songs in JuK (and Kiwi, too, but that's a different battle 
entirely), etc.

This bug was (apparently) introduced in Qt 3.1.2. I propose that we 
either fix it in KListView by having KLV::setDragEnabled call 
QLVI::setDragEnabled for its children, or having TrollTech fix 
QListView's clickEvent checks.

-clee