[gnome-builder] gui: check for non-NULL VCS before short-circuit

[Christian Hergert <chergert src gnome org>]

commit 513fb5bc97ee81baee28cc1a2aa2e357e622195a
Author: Christian Hergert <chergert redhat com>
Date:   Fri Jun 14 11:31:08 2019 -0700

    gui: check for non-NULL VCS before short-circuit

 src/libide/gui/ide-workbench.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/libide/gui/ide-workbench.c b/src/libide/gui/ide-workbench.c
index f1a1d31ce..19c71b91e 100644
--- a/src/libide/gui/ide-workbench.c
+++ b/src/libide/gui/ide-workbench.c
@@ -2268,7 +2268,7 @@ ide_workbench_set_vcs (IdeWorkbench *self,
   g_return_if_fail (IDE_IS_WORKBENCH (self));
   g_return_if_fail (!vcs || IDE_IS_VCS (vcs));
 
-  if (vcs == self->vcs)
+  if (self->vcs != NULL && vcs == self->vcs)
     return;
 
   if (vcs == NULL)