[rhythmbox] metadata: don't crash if we can't create a discoverer

[Jonathan Matthew <jmatthew src gnome org>]

commit f78c13e39f1f546ad6bd0f3f3d67c3613b2eb629
Author: Jonathan Matthew <jonathan d14n org>
Date:   Tue Feb 5 23:13:59 2013 +1000

    metadata: don't crash if we can't create a discoverer
    
    https://bugzilla.redhat.com/show_bug.cgi?id=755888

 metadata/rb-metadata-gst.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)
---
diff --git a/metadata/rb-metadata-gst.c b/metadata/rb-metadata-gst.c
index 2ec620c..19ab56c 100644
--- a/metadata/rb-metadata-gst.c
+++ b/metadata/rb-metadata-gst.c
@@ -168,7 +168,10 @@ rb_metadata_load (RBMetaData *md, const char *uri, GError **error)
 
 	rb_metadata_reset (md);
 
-	discoverer = gst_discoverer_new (30 * GST_SECOND, NULL);
+	discoverer = gst_discoverer_new (30 * GST_SECOND, error);
+	if (*error != NULL)
+		return;
+
 	md->priv->info = gst_discoverer_discover_uri (discoverer, g_strdup (uri), error);
 	g_object_unref (discoverer);
 
@@ -817,6 +820,9 @@ rb_metadata_get (RBMetaData *md, RBMetaDataField field, GValue *ret)
 	GValue gstvalue = {0, };
 	GstClockTime duration;
 
+	if (md->priv->info == NULL)
+		return FALSE;
+
 	/* special cases: mostly duration */
 	switch (field) {
 	case RB_METADATA_FIELD_DURATION: