[gnome-builder] clang: be defensive

[Christian Hergert <chergert src gnome org>]

commit 3620475d9de8715952afd290971e9c1b6ab16f4d
Author: Christian Hergert <christian hergert me>
Date:   Sun Sep 27 18:19:29 2015 -0700

    clang: be defensive
    
    Shouldn't happen, but annoying when we change things and forget it later.

 plugins/clang/ide-clang-completion-item.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/plugins/clang/ide-clang-completion-item.c b/plugins/clang/ide-clang-completion-item.c
index 322b16a..7d49993 100644
--- a/plugins/clang/ide-clang-completion-item.c
+++ b/plugins/clang/ide-clang-completion-item.c
@@ -336,6 +336,7 @@ ide_clang_completion_item_set_property (GObject      *object,
       break;
 
     case PROP_RESULTS:
+      g_clear_pointer (&self->results, ide_ref_ptr_unref);
       self->results = g_value_dup_boxed (value);
       break;