[gtk] widget: Fix a memory leak

[Matthias Clasen <matthiasc src gnome org>]

commit 08d4bb47856c68d09239512eda1e5b82c75c33b0
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Dec 25 00:40:32 2019 -0500

    widget: Fix a memory leak
    
    The transform passed to gtk_widget_allocate is
    transfer full, so we must consume the reference
    before returning.

 gtk/gtkwidget.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/gtk/gtkwidget.c b/gtk/gtkwidget.c
index 1c03acb20f..c1bd09842e 100644
--- a/gtk/gtkwidget.c
+++ b/gtk/gtkwidget.c
@@ -4317,7 +4317,10 @@ gtk_widget_allocate (GtkWidget    *widget,
   gtk_widget_push_verify_invariants (widget);
 
   if (!priv->visible && !GTK_IS_ROOT (widget))
-    goto out;
+    {
+      gsk_transform_unref (transform);
+      goto out;
+    }
 
 #ifdef G_ENABLE_DEBUG
   if (GTK_DISPLAY_DEBUG_CHECK (_gtk_widget_get_display (widget), RESIZE))