Merge branch 'ebassi/a11y-leak' into 'master'

a11y: Plug a leak in the AT-SPI context

Closes #3450

See merge request GNOME/gtk!2926

gtk/a11y/gtkatspicontext.c

@@ -1519,6 +1519,7 @@ gtk_at_spi_context_unrealize (GtkATContext *context)
   gtk_atspi_disconnect_selection_signals (accessible);
   gtk_at_spi_context_unregister_object (self);
 
+  g_clear_pointer (&self->context_path, g_free);
   g_clear_object (&self->root);
 }