* gtk/gtkhandlebox.c: Grab on widget->window,
not on handlebox->bin_window. This means we don't
have to worry about ungrabbing while reparenting.
Don't make a GTK+ grab - that wasn't necessary.
* gtk/gtkhandlebox.c: Only compute the root -> desk
offset once, when starting the drag, instead
of continuously. This should solve the *Bad Window*
errors that were occurring because of race conditions
with the WM.
* gtk/gtkhandlebox.c: Completely reworked the
the logic of reattachment. We introduce the
concept of the "snap edge", which is an edge
that needs to be aligned for reattachmed.
We set a reasonable default from
handlebox->handle_position, but an application
might want to change this in some circumstances.