[gedit] statusbar: fix error in last patch

[Paolo Borelli <pborelli src gnome org>]

commit 5f5887263d089dac1635693caa67a11e52d46e20
Author: Paolo Borelli <pborelli gnome org>
Date:   Mon Apr 20 22:47:13 2015 +0200

    statusbar: fix error in last patch

 gedit/gedit-statusbar.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gedit/gedit-statusbar.c b/gedit/gedit-statusbar.c
index de2b8ed..44cba43 100644
--- a/gedit/gedit-statusbar.c
+++ b/gedit/gedit-statusbar.c
@@ -33,6 +33,8 @@
 
 struct _GeditStatusbar
 {
+       GtkStatusbar  parent_instance;
+
        GtkWidget     *error_frame;
        GtkWidget     *error_image;
        GtkWidget     *state_frame;