diff --git a/headers/private/servers/app/Decorator.h b/headers/private/servers/app/Decorator.h
index 7d7dd10469..bd044ad487 100644
--- a/headers/private/servers/app/Decorator.h
+++ b/headers/private/servers/app/Decorator.h
@@ -115,10 +115,13 @@ class Decorator {
 
 	virtual	void				MoveBy(float x, float y);
 	virtual	void				MoveBy(BPoint pt);
-	virtual	BRect				SlideTab(float dx, float dy = 0);
 	virtual	void				ResizeBy(float x, float y);
 	virtual	void				ResizeBy(BPoint pt);
 
+	virtual	void				SetTabLocation(float location) {}
+	virtual	float				TabLocation() const
+									{ return 0.0; }
+
 	virtual	void				Draw(BRect r);
 	virtual	void				Draw();
 	virtual	void				DrawClose();