[gnome-builder/wip/gtk4-port] libide/gui: fix parent widget type in class definition

[Christian Hergert <chergert src gnome org>]

commit 863a46362e2604d13a3edee3dcb1834082aab1f4
Author: Christian Hergert <chergert redhat com>
Date:   Tue Mar 29 12:02:44 2022 -0700

    libide/gui: fix parent widget type in class definition

 src/libide/gui/ide-header-bar.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libide/gui/ide-header-bar.h b/src/libide/gui/ide-header-bar.h
index f111e8b15..68bce3bf4 100644
--- a/src/libide/gui/ide-header-bar.h
+++ b/src/libide/gui/ide-header-bar.h
@@ -46,7 +46,7 @@ G_DECLARE_DERIVABLE_TYPE (IdeHeaderBar, ide_header_bar, IDE, HEADER_BAR, GtkWidg
 
 struct _IdeHeaderBarClass
 {
-  GtkWidget parent_class;
+  GtkWidgetClass parent_class;
 };
 
 IDE_AVAILABLE_IN_ALL