[mutter] xwayland: Fix mime type atom list leak on DnD with more than 3 types

[Carlos Garnacho <carlosg src gnome org>]

commit 509e9ca5a0009268faaa7373c984e2df710a48e2
Author: Sebastian Keller <skeller gnome org>
Date:   Tue Mar 10 23:27:35 2020 +0100

    xwayland: Fix mime type atom list leak on DnD with more than 3 types
    
    Found using the clang static analyzer
    
    https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1117

 src/wayland/meta-xwayland-dnd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/wayland/meta-xwayland-dnd.c b/src/wayland/meta-xwayland-dnd.c
index 9821f2dc3..6b75362ba 100644
--- a/src/wayland/meta-xwayland-dnd.c
+++ b/src/wayland/meta-xwayland-dnd.c
@@ -171,7 +171,7 @@ xdnd_send_enter (MetaXWaylandDnd *dnd,
       /* We have more than 3 mimetypes, we must set up
        * the mimetype list as a XdndTypeList property.
        */
-      Atom *atomlist;
+      g_autofree Atom *atomlist = NULL;
       gint i = 0;
 
       xev.xclient.data.l[1] |= 1;