a #GtkWidget which should be a drag destination for @palette
the flags that specify what actions GTK+ should take for drops on that widget
the #GtkToolPaletteDragTargets which the widget should support
the #GdkDragActions which the widget should suppport
2.20
Sets @palette as drag source (see gtk_tool_palette_set_drag_source()) and sets @widget as a drag destination for drags from @palette. See gtk_drag_dest_set().