Fix build by adding include

build failed with a GTK_IS_VIEWPORT link error

diff --git a/gtk/gtkscrolledwindow.c b/gtk/gtkscrolledwindow.c
index 3bd5f3b295052fa4be294572c2dbe8bdf4d688bd..12fa27d0d3868a41252c444dffb5a39c96d66491 100644 (file)
--- a/gtk/gtkscrolledwindow.c
+++ b/gtk/gtkscrolledwindow.c
@@ -34,6 +34,7 @@
 #include "gtkscrollbar.h"
 #include "gtkscrolledwindow.h"
 #include "gtkwindow.h"
+#include "gtkviewport.h"
 #include "gtkprivate.h"
 #include "gtktypebuiltins.h"
 #include "gtkintl.h"