[json-glib/wip/ordered-iter] Document the iteration order for foreach_member()

[Emmanuele Bassi <ebassi src gnome org>]

commit b262e4e711af1b1cb06489b9b5f61a9641e0e8db
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Mon Aug 24 12:42:21 2020 +0100

    Document the iteration order for foreach_member()
    
    The iteration order is the insertion order, and has been for a long
    time.

 json-glib/json-object.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/json-glib/json-object.c b/json-glib/json-object.c
index c67b687..a17fd6d 100644
--- a/json-glib/json-object.c
+++ b/json-glib/json-object.c
@@ -957,6 +957,9 @@ json_object_remove_member (JsonObject  *object,
  * from within the iterator @func, but it is not safe to add or
  * remove members from the @object.
  *
+ * The order in which the @object members are iterated is the
+ * insertion order.
+ *
  * Since: 0.8
  */
 void