[libgdata] gd: Fix documentation comment

[Philip Withnall <pwithnall src gnome org>]

commit 5af3a0722daf2711f05665a63508b8fd34b70df8
Author: Philip Withnall <philip tecnocode co uk>
Date:   Tue Aug 27 23:42:35 2013 -0600

    gd: Fix documentation comment

 gdata/gd/gdata-gd-when.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gdata/gd/gdata-gd-when.c b/gdata/gd/gdata-gd-when.c
index 656d878..9d347cb 100644
--- a/gdata/gd/gdata-gd-when.c
+++ b/gdata/gd/gdata-gd-when.c
@@ -451,6 +451,9 @@ gdata_gd_when_set_start_time (GDataGDWhen *self, gint64 start_time)
  *
  * If the end time is unset, <code class="literal">-1</code> will be returned.
  *
+ * Return value: the UNIX timestamp for the end time of the event, or
+ * <code class="literal">-1</code>
+ *
  * Since: 0.4.0
  **/
 gint64