[libgda] proxy: Fix memory leak

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit a494d2e8dec464eb7c8717af8a3466fa0f6e203d
Author: Daniel Espinosa Ortiz <esodan gmail com>
Date:   Sun Mar 10 18:44:38 2019 -0600

    proxy: Fix memory leak

 libgda/gda-data-proxy.c | 2 ++
 1 file changed, 2 insertions(+)
---
diff --git a/libgda/gda-data-proxy.c b/libgda/gda-data-proxy.c
index a939f7eb2..4f66bc020 100644
--- a/libgda/gda-data-proxy.c
+++ b/libgda/gda-data-proxy.c
@@ -955,6 +955,8 @@ gda_data_proxy_set_property (GObject *object,
 
                                do_init (proxy);
                                already_set = TRUE;
+                               g_object_unref (priv->model);
+                               priv->model = NULL;
                        }
 
                        model = (GdaDataModel*) g_value_get_object (value);