[libhandy] window-mixin: Correctly destroy the children

[Adrien Plazas <aplazas src gnome org>]

commit 029787e4f60b60d662a90ef8a6308e5b23977e68
Author: Alexander Mikhaylenko <alexm gnome org>
Date:   Wed Sep 2 00:40:56 2020 +0500

    window-mixin: Correctly destroy the children
    
    Fix a memory leak.
    
    Signed-off-by: Alexander Mikhaylenko <alexm gnome org>

 src/hdy-window-mixin.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)
---
diff --git a/src/hdy-window-mixin.c b/src/hdy-window-mixin.c
index d240202a..871a54c2 100644
--- a/src/hdy-window-mixin.c
+++ b/src/hdy-window-mixin.c
@@ -470,13 +470,9 @@ hdy_window_mixin_draw (HdyWindowMixin *self,
 void
 hdy_window_mixin_destroy (HdyWindowMixin *self)
 {
-  if (self->titlebar) {
-    hdy_window_mixin_remove (self, self->titlebar);
-    self->titlebar = NULL;
-  }
-
   if (self->content) {
     hdy_window_mixin_remove (self, self->content);
+    gtk_widget_destroy (self->content);
     self->content = NULL;
     self->child = NULL;
   }