[gnome-session] main: Remove GNOME_DESKTOP_SESSION_ID envvar

[Ray Strode <halfline src gnome org>]

commit 00e0e6226371d53f651cc881e74c0543192c94a8
Author: Bastien Nocera <hadess hadess net>
Date:   Wed Nov 15 16:44:13 2017 +0100

    main: Remove GNOME_DESKTOP_SESSION_ID envvar
    
    It was re-added "for compatibility reasons" nearly 10 years ago in
    commit b7c806503. There's really no need to keep this compatibility any
    longer.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=790387

 gnome-session/main.c |    5 -----
 1 files changed, 0 insertions(+), 5 deletions(-)
---
diff --git a/gnome-session/main.c b/gnome-session/main.c
index b1ac385..9a7f554 100644
--- a/gnome-session/main.c
+++ b/gnome-session/main.c
@@ -408,11 +408,6 @@ main (int argc, char **argv)
                 g_free (ibus_path);
         }
 
-        /* Some third-party programs rely on GNOME_DESKTOP_SESSION_ID to
-         * detect if GNOME is running. We keep this for compatibility reasons.
-         */
-        gsm_util_setenv ("GNOME_DESKTOP_SESSION_ID", "this-is-deprecated");
-
         /* We want to use the GNOME menus which has the designed categories.
          */
         gsm_util_setenv ("XDG_MENU_PREFIX", "gnome-");