[gtk/wip/exalm/test: 30/37] tests: Fix teststack "add icon" button

[Alexander Mikhaylenko <alexm src gnome org>]

commit 1d2af907fcdd642ab27cafc864684e042f8b6a6d
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Mon May 11 19:27:41 2020 +0500

    tests: Fix teststack "add icon" button

 tests/teststack.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tests/teststack.c b/tests/teststack.c
index 00b21226a4..dbbb219467 100644
--- a/tests/teststack.c
+++ b/tests/teststack.c
@@ -37,7 +37,7 @@ toggle_icon_name (GtkWidget *button, gpointer data)
   gboolean active = gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (button));
   GtkStackPage *page;
 
-  page = gtk_stack_get_page (GTK_STACK (gtk_widget_get_parent (button)), button);
+  page = gtk_stack_get_page (GTK_STACK (stack), w1);
   g_object_set (page, "icon-name", active ? "edit-find-symbolic" : NULL, NULL);
 }