[devhelp] BookTree: improve doc of get_selected_book()

[Sébastien Wilmet <swilmet src gnome org>]

commit 8c15331339a78e52ec71a5413b636f561e0f5dba
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Tue May 15 15:44:15 2018 +0200

    BookTree: improve doc of get_selected_book()

 devhelp/dh-book-tree.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/devhelp/dh-book-tree.c b/devhelp/dh-book-tree.c
index 1d794b7..b204340 100644
--- a/devhelp/dh-book-tree.c
+++ b/devhelp/dh-book-tree.c
@@ -1024,9 +1024,9 @@ out:
  * dh_book_tree_get_selected_book:
  * @tree: a #DhBookTree.
  *
- * Returns: (nullable) (transfer full): the #DhLink of the selected book, or
- * %NULL if there is no selection. Unref with dh_link_unref() when no longer
- * needed.
+ * Returns: (nullable) (transfer full): the #DhLink of type %DH_LINK_TYPE_BOOK
+ * of the selected book, or %NULL if there is no selection. Unref with
+ * dh_link_unref() when no longer needed.
  */
 DhLink *
 dh_book_tree_get_selected_book (DhBookTree *tree)