[devhelp] BookTree: add another FIXME comment about language management

[Sébastien Wilmet <swilmet src gnome org>]

commit 56f8389fe631dd46a3d23d9d8a3edb71089e0664
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Jul 7 16:43:00 2017 +0200

    BookTree: add another FIXME comment about language management

 src/dh-book-tree.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/src/dh-book-tree.c b/src/dh-book-tree.c
index 2231b15..70e93f7 100644
--- a/src/dh-book-tree.c
+++ b/src/dh-book-tree.c
@@ -117,6 +117,10 @@ book_tree_setup_selection (DhBookTree *tree)
  *  - An exact match of the language group
  *  - Or the language group which should be just after our given language group.
  *  - Or both.
+ *
+ * FIXME: not great code. Maybe add a new column in the GtkTreeModel storing a
+ * DhLanguage object. Instead of @language as a string, it would be a
+ * DhLanguage.
  */
 static void
 book_tree_find_language_group (DhBookTree  *tree,