[gtk/tintou/dropdown-annotations] dropdown: Annotate the get_selected_item method

[Corentin Noël <corentinnoel src gnome org>]

commit 721396b6d6e66b90a41fb6d6079ac84d144fa4b9
Author: Corentin Noël <corentin noel collabora com>
Date:   Fri Jun 26 09:59:12 2020 +0200

    dropdown: Annotate the get_selected_item method
    
    We need to specify the type as we already know that it is at least a GObject and in case of no selection, 
NULL is returned.

 gtk/gtkdropdown.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gtk/gtkdropdown.c b/gtk/gtkdropdown.c
index 8430c1450b..721493dd3f 100644
--- a/gtk/gtkdropdown.c
+++ b/gtk/gtkdropdown.c
@@ -821,7 +821,7 @@ gtk_drop_down_get_selected (GtkDropDown *self)
  *
  * Gets the selected item. If no item is selected, %NULL is returned.
  *
- * Returns: (transfer none): The selected item
+ * Returns: (transfer none) (type GObject) (nullable): The selected item
  */
 gpointer
 gtk_drop_down_get_selected_item (GtkDropDown *self)