[gtk] scale: Fix an uninitialized value

[Timm Bäder <baedert src gnome org>]

commit 05cdce2e8dbb7eb677995f3231802893be87d21f
Author: Timm Bäder <mail baedert org>
Date:   Fri Aug 9 10:33:43 2019 +0200

    scale: Fix an uninitialized value

 gtk/gtkscale.c | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/gtk/gtkscale.c b/gtk/gtkscale.c
index 887af19200..9627d278f5 100644
--- a/gtk/gtkscale.c
+++ b/gtk/gtkscale.c
@@ -597,6 +597,7 @@ gtk_scale_size_allocate (GtkWidget *widget,
           marks_rect.x = 0;
           marks_rect.y = 0;
           marks_rect.width = marks_width;
+          marks_rect.height = range_rect.height;
           gtk_widget_size_allocate (priv->top_marks_widget, &marks_rect, -1);
         }