[glib] gbytes: Clarify nullability for g_bytes_unref() in docs

[Philip Withnall <pwithnall src gnome org>]

commit ed3d2d9c67da11c7a25faeac7b5c4b3c4d4af873
Author: Umang Jain <mailumangjain gmail com>
Date:   Thu Dec 7 01:18:47 2017 +0530

    gbytes: Clarify nullability for g_bytes_unref() in docs
    
    https://bugzilla.gnome.org/show_bug.cgi?id=791318

 glib/gbytes.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/glib/gbytes.c b/glib/gbytes.c
index 747c41b..81dc9db 100644
--- a/glib/gbytes.c
+++ b/glib/gbytes.c
@@ -294,7 +294,7 @@ g_bytes_ref (GBytes *bytes)
  * @bytes: (nullable): a #GBytes
  *
  * Releases a reference on @bytes.  This may result in the bytes being
- * freed.
+ * freed. If @bytes is %NULL, it will return immediately.
  *
  * Since: 2.32
  */