[libgda] GdaVConnectionDataModel: fix context object get weak ref

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit fc43197461524741140a6ffaa130c828bd31a732
Author: Daniel Espinosa Ortiz <esodan gmail com>
Date:   Tue Feb 12 16:23:14 2019 -0600

    GdaVConnectionDataModel: fix context object get weak ref

 libgda/sqlite/virtual/gda-vconnection-data-model.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
---
diff --git a/libgda/sqlite/virtual/gda-vconnection-data-model.c 
b/libgda/sqlite/virtual/gda-vconnection-data-model.c
index 29ff07824..4be14dc66 100644
--- a/libgda/sqlite/virtual/gda-vconnection-data-model.c
+++ b/libgda/sqlite/virtual/gda-vconnection-data-model.c
@@ -608,8 +608,10 @@ static void
 vcontext_free (VContext *context)
 {
        GObject *obj = g_weak_ref_get (&(context->context_object));
-       g_hash_table_remove (context->vtable->context.hash, obj);
-       g_object_unref (obj);
+       if (obj) {
+               g_hash_table_remove (context->vtable->context.hash, obj);
+               g_object_unref (obj);
+       }
        if (context->context_data) {
                g_array_free (context->context_data, TRUE);
                context->context_data = NULL;