[glib] Improve documentation for g_error_matches()

[Benjamin Otte <otte src gnome org>]

commit 981d14e85ccf8d1dc721bd44e030728eff9b2501
Author: Benjamin Otte <otte gnome org>
Date:   Thu Aug 6 18:17:32 2009 +0200

    Improve documentation for g_error_matches()

 glib/gerror.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/glib/gerror.c b/glib/gerror.c
index ea454d5..4327f9a 100644
--- a/glib/gerror.c
+++ b/glib/gerror.c
@@ -166,12 +166,13 @@ g_error_copy (const GError *error)
 
 /**
  * g_error_matches:
- * @error: a #GError
+ * @error: a #GError or %NULL
  * @domain: an error domain
  * @code: an error code
  *
  * Returns %TRUE if @error matches @domain and @code, %FALSE
- * otherwise.
+ * otherwise. In particular, when @error is %NULL, %FALSE will
+ * be returned.
  *
  * Return value: whether @error has @domain and @code
  */