[gtk+] Fix transfer annotation for tree_model parameter of gtk_tree_get_row_drag_data() and add nullable, o

[Matthias Clasen <matthiasc src gnome org>]

commit f4dee9b682b5ef0b00d882f0327f0cbdd317afaf
Author: Christoph Reiter <reiter christoph gmail com>
Date:   Mon Jan 19 18:06:03 2015 +0100

    Fix transfer annotation for tree_model parameter of gtk_tree_get_row_drag_data() and add nullable, 
optional
    
    The GtkSelectionData does not own the model set with
    gtk_tree_set_row_drag_data so change the out param to "transfer none".
    This fixes a crash after multiple DnD actions due to the bindings
    stealing a reference each time this function is called.
    
    This also adds nullable and optional annotations for tree_model and path while at it.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=743193

 gtk/gtktreednd.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtktreednd.c b/gtk/gtktreednd.c
index 57b6240..1e230fa 100644
--- a/gtk/gtktreednd.c
+++ b/gtk/gtktreednd.c
@@ -305,8 +305,8 @@ gtk_tree_set_row_drag_data (GtkSelectionData *selection_data,
 /**
  * gtk_tree_get_row_drag_data:
  * @selection_data: a #GtkSelectionData
- * @tree_model: (out): a #GtkTreeModel
- * @path: (out): row in @tree_model
+ * @tree_model: (nullable) (optional) (transfer none) (out): a #GtkTreeModel
+ * @path: (nullable) (optional) (out): row in @tree_model
  * 
  * Obtains a @tree_model and @path from selection data of target type
  * %GTK_TREE_MODEL_ROW. Normally called from a drag_data_received handler.