[glib] Binding: bind_property’s @notify func is nullable

[Daniel Boles <dboles src gnome org>]

commit 54b04f74bdccc6581b47fd34983394fa7569424d
Author: Daniel Boles <dboles src gnome org>
Date:   Mon Jan 1 16:12:15 2018 +0000

    Binding: bind_property’s @notify func is nullable
    
    This is for destroying resources needed by transformations. But the user
    may not need any such resources. Make it obvious that, instead of having
    to point to a no-op function, @notify is checked and not called if NULL.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=792098

 gobject/gbinding.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gobject/gbinding.c b/gobject/gbinding.c
index f92fad8..899dc84 100644
--- a/gobject/gbinding.c
+++ b/gobject/gbinding.c
@@ -781,8 +781,8 @@ g_binding_unbind (GBinding *binding)
  *     from the @target to the @source, or %NULL to use the default
  * @user_data: custom data to be passed to the transformation functions,
  *     or %NULL
- * @notify: function to be called when disposing the binding, to free the
- *     resources used by the transformation functions
+ * @notify: (nullable): a function to call when disposing the binding, to free
+ *     resources used by the transformation functions, or %NULL if not required
  *
  * Complete version of g_object_bind_property().
  *