[glom] Add a TODO comment.

[Murray Cumming <murrayc src gnome org>]

commit e5037270f40890e023a666fd2fbf0d4c6557e5ee
Author: Murray Cumming <murrayc murrayc com>
Date:   Thu Mar 10 10:06:57 2016 +0100

    Add a TODO comment.

 glom/mode_data/box_data_list_related.cc |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/glom/mode_data/box_data_list_related.cc b/glom/mode_data/box_data_list_related.cc
index 13b5f06..2f9f70c 100644
--- a/glom/mode_data/box_data_list_related.cc
+++ b/glom/mode_data/box_data_list_related.cc
@@ -442,7 +442,7 @@ void Box_Data_List_Related::create_layout()
     for(const auto& child_item : child_items)
     {
       //TODO: Set the whole thing as read-only instead:
-      if(m_read_only)
+      if(m_read_only) //TODO: Valgrind says "Conditional jump or move depends on uninitialised value(s)"
         child_item->set_editable(false);
 
       auto child_field = std::dynamic_pointer_cast<const LayoutItem_Field>(child_item);