[gtk+/portal] Don't leak a GError

[Matthias Clasen <matthiasc src gnome org>]

commit 86c2dcc1c829c077ad6fc5e8c50e0bb463b51db9
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Jul 6 20:22:55 2016 -0400

    Don't leak a GError
    
    Spotted by Cosimo.

 gtk/gtkfilechoosernativeportal.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkfilechoosernativeportal.c b/gtk/gtkfilechoosernativeportal.c
index b1d4f7c..12377d7 100644
--- a/gtk/gtkfilechoosernativeportal.c
+++ b/gtk/gtkfilechoosernativeportal.c
@@ -184,7 +184,8 @@ open_file_msg_cb (GObject *source_object,
     {
       if (!data->hidden)
         _gtk_native_dialog_emit_response (GTK_NATIVE_DIALOG (self), GTK_RESPONSE_DELETE_EVENT);
-      g_warning ("Can't open portal file chooser: %s\n", error->message);
+      g_warning ("Can't open portal file chooser: %s", error->message);
+      g_error_free (error);
       filechooser_portal_data_free (data);
       return;
     }