[gtk] types: Move GTK_INVALID_LIST_POSITION here

[Benjamin Otte <otte src gnome org>]

commit 552db7cb0837c8c6e77dd9bbd0ccb0e4eb3ace64
Author: Benjamin Otte <otte redhat com>
Date:   Thu Dec 12 18:20:29 2019 +0100

    types: Move GTK_INVALID_LIST_POSITION here
    
    I have no idea where it should go really - maybe glib?
    
    It certainly shouldn't require everybody including selectionmodel code
    just to get at this value.

 gtk/gtksingleselection.h | 12 ------------
 gtk/gtktypes.h           | 12 ++++++++++++
 2 files changed, 12 insertions(+), 12 deletions(-)
---
diff --git a/gtk/gtksingleselection.h b/gtk/gtksingleselection.h
index 74107fcc06..f9bbcae9e9 100644
--- a/gtk/gtksingleselection.h
+++ b/gtk/gtksingleselection.h
@@ -26,18 +26,6 @@ G_BEGIN_DECLS
 
 #define GTK_TYPE_SINGLE_SELECTION (gtk_single_selection_get_type ())
 
-/**
- * GTK_INVALID_LIST_POSITION:
- *
- * The value used to refer to a guaranteed invalid position in a #GListModel. This
- * value may be returned from some functions, others may accept it as input.
- * Its interpretion may differ for different functions.
- *
- * Refer to each function's documentation for if this value is allowed and what it
- * does.
- */
-#define GTK_INVALID_LIST_POSITION (G_MAXUINT)
-
 GDK_AVAILABLE_IN_ALL
 G_DECLARE_FINAL_TYPE (GtkSingleSelection, gtk_single_selection, GTK, SINGLE_SELECTION, GObject)
 
diff --git a/gtk/gtktypes.h b/gtk/gtktypes.h
index 83a462448d..d8ad82be0f 100644
--- a/gtk/gtktypes.h
+++ b/gtk/gtktypes.h
@@ -58,6 +58,18 @@ typedef GClosure*       (* GtkBuilderClosureFunc)               (GtkBuilder
                                                                  gpointer                user_data,
                                                                  GError                **error);
 
+/**
+ * GTK_INVALID_LIST_POSITION:
+ *
+ * The value used to refer to a guaranteed invalid position in a #GListModel. This
+ * value may be returned from some functions, others may accept it as input.
+ * Its interpretion may differ for different functions.
+ *
+ * Refer to each function's documentation for if this value is allowed and what it
+ * does.
+ */
+#define GTK_INVALID_LIST_POSITION (G_MAXUINT)
+
 G_END_DECLS
 
 #endif /* __GTK_TYPES_H__ */