gtkdnd: Set the icon helper from the drag site onto the context
If the icon happened to come from the drag site icon helper (ie. set through gtk_drag_source_set_icon*), it would be referenced on the GtkDragInfo, but not hooked into its context. This results on non visible drag windows, until set_icon_helper() happened to be called on some path.
Showing with 5 additions and 1 deletion