[nautilus] nautilus-file: Fix segfault on batch rename for file gone

[Alexandru-Ionut Pandelea <alexpandelea src gnome org>]

commit edf815992e2b30d688fa7e728f1fdb24f04f0ac5
Author: Alexandru Pandelea <alexandru pandelea gmail com>
Date:   Wed Sep 7 22:15:56 2016 +0300

    nautilus-file: Fix segfault on batch rename for file gone
    
    If one or more files are deleted during a batch rename and click rename,
    Nautilus would seg fault.
    
    The problem is that in the function nautilus_file_rename_handle_file_gone
    there was called a callback that was NULL. For batch renaming, there is no
    need for a callback here.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=770968

 src/nautilus-file.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/nautilus-file.c b/src/nautilus-file.c
index 57e5377..5412758 100644
--- a/src/nautilus-file.c
+++ b/src/nautilus-file.c
@@ -2374,7 +2374,8 @@ nautilus_file_rename_handle_file_gone (NautilusFile                  *file,
         nautilus_file_changed (file);
         error = g_error_new (G_IO_ERROR, G_IO_ERROR_NOT_FOUND,
                              _("File not found"));
-        (*callback)(file, NULL, error, callback_data);
+        if (callback)
+            (*callback)(file, NULL, error, callback_data);
         g_error_free (error);
         return TRUE;
     }