[gnome-builder] gettext: check id before dereferencing

[Christian Hergert <chergert src gnome org>]

commit bae76d1139b59584a7564fa154cd0d95b3cc7e94
Author: Christian Hergert <chergert redhat com>
Date:   Mon Feb 15 12:29:26 2016 -0800

    gettext: check id before dereferencing

 plugins/gettext/ide-gettext-diagnostic-provider.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/plugins/gettext/ide-gettext-diagnostic-provider.c 
b/plugins/gettext/ide-gettext-diagnostic-provider.c
index 576ae20..b1354d3 100644
--- a/plugins/gettext/ide-gettext-diagnostic-provider.c
+++ b/plugins/gettext/ide-gettext-diagnostic-provider.c
@@ -364,9 +364,12 @@ id_to_xgettext_language (const gchar *id)
   };
   gsize i;
 
-  for (i = 0; i < G_N_ELEMENTS (id_to_lang); i++)
-    if (strcmp (id, id_to_lang[i].id) == 0)
-      return id_to_lang[i].lang;
+  if (id != NULL)
+    {
+      for (i = 0; i < G_N_ELEMENTS (id_to_lang); i++)
+        if (strcmp (id, id_to_lang[i].id) == 0)
+          return id_to_lang[i].lang;
+    }
 
   return NULL;
 }