[empathy] document when/how Folks is used in empathy-chat

[Guillaume Desmottes <gdesmott src gnome org>]

commit 61c27ce3a19ab2b74ca1e0ef9ca058c10457f98f
Author: Guillaume Desmottes <guillaume desmottes collabora co uk>
Date:   Thu Sep 27 11:57:20 2012 +0200

    document when/how Folks is used in empathy-chat

 src/empathy-chat.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)
---
diff --git a/src/empathy-chat.c b/src/empathy-chat.c
index 0f7173a..4da3f0a 100644
--- a/src/empathy-chat.c
+++ b/src/empathy-chat.c
@@ -142,7 +142,14 @@ main (int argc,
   theme_mgr = empathy_theme_manager_dup_singleton ();
 
   /* Keep the individual manager alive so we won't fetch everything from Folks
-   * each time we need to use it. */
+   * each time we need to use it. The individual manager (and so Folks) is
+   * needed to know to which FolksIndividual a TpContact belongs, including:
+   * - empathy_chat_get_contact_menu: to list all the personas of the contact
+   * - empathy_display_individual_info: to invoke gnome-contacts with the
+   *   FolksIndividual.id of the contact
+   * - chat-window:drag_data_received_individual_id: to find the individual
+   *   associated with the ID we received from the DnD in order to invite him.
+   */
   individual_mgr = empathy_individual_manager_dup_singleton ();
 
   if (g_getenv ("EMPATHY_PERSIST") != NULL)