[gnome-builder] clang-service: fix preconditions for start/stop

[Christian Hergert <chergert src gnome org>]

commit da74c0bb5b752871efe26f370a9e275d7a08c9d4
Author: Christian Hergert <chergert redhat com>
Date:   Sat Oct 29 21:44:08 2016 -0700

    clang-service: fix preconditions for start/stop

 plugins/clang/ide-clang-service.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/plugins/clang/ide-clang-service.c b/plugins/clang/ide-clang-service.c
index 17128e6..486a731 100644
--- a/plugins/clang/ide-clang-service.c
+++ b/plugins/clang/ide-clang-service.c
@@ -547,7 +547,7 @@ ide_clang_service_start (IdeService *service)
   IdeClangService *self = (IdeClangService *)service;
 
   g_return_if_fail (IDE_IS_CLANG_SERVICE (self));
-  g_return_if_fail (!self->index);
+  g_return_if_fail (self->index == NULL);
 
   self->cancellable = g_cancellable_new ();
 
@@ -575,7 +575,7 @@ ide_clang_service_stop (IdeService *service)
   IdeClangService *self = (IdeClangService *)service;
 
   g_return_if_fail (IDE_IS_CLANG_SERVICE (self));
-  g_return_if_fail (!self->index);
+  g_return_if_fail (self->index != NULL);
 
   g_cancellable_cancel (self->cancellable);
   g_clear_object (&self->units_cache);