[sound-juicer/gnome-3-18] Fix duration detection in EggPlayPreview

[Phillip Wood <pwood src gnome org>]

commit 7867c868fa7b6282ff71932e4cd1f10a414b68b7
Author: Phillip Wood <phillip wood dunelm org uk>
Date:   Sun Feb 22 10:45:28 2015 +0000

    Fix duration detection in EggPlayPreview
    
    To get the track duration EggPlayPreview was checking for messages of
    type GST_MESSAGE_DURATION and then calling
    gst_message_parse_duration() which always returns a duration of
    -1. This meant that the track duration was always zero which broke
    seeking. It should check for messages of type
    GST_MESSAGE_DURATION_CHANGED and query playbin for the new duration
    instead.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=744941

 src/egg-play-preview.c |   13 ++++++-------
 1 files changed, 6 insertions(+), 7 deletions(-)
---
diff --git a/src/egg-play-preview.c b/src/egg-play-preview.c
index 3dafb51..9c30251 100644
--- a/src/egg-play-preview.c
+++ b/src/egg-play-preview.c
@@ -582,7 +582,6 @@ static gboolean
 _process_bus_messages (GstBus *bus, GstMessage *msg, EggPlayPreview *play_preview)
 {
        EggPlayPreviewPrivate *priv;
-       GstFormat format = GST_FORMAT_TIME;
        GstTagList *tag_list;
        gint64 duration;
        GstState state;
@@ -591,16 +590,16 @@ _process_bus_messages (GstBus *bus, GstMessage *msg, EggPlayPreview *play_previe
        priv = GET_PRIVATE (play_preview);
 
        switch (GST_MESSAGE_TYPE (msg)) {
-       case GST_MESSAGE_DURATION:
-               gst_message_parse_duration (msg, &format, (gint64*) &duration);
-
-               if (format != GST_FORMAT_TIME)
+       case GST_MESSAGE_DURATION_CHANGED:
+               if (!gst_element_query_duration (priv->playbin, GST_FORMAT_TIME, &duration))
                        break;
 
-               priv->duration = duration / GST_SECOND;
+               duration /= GST_SECOND;
+               if (priv->duration == duration)
+                       break;
 
+               priv->duration = duration;
                g_object_notify (G_OBJECT (play_preview), "duration");
-
                _ui_update_duration (play_preview);
                break;