[banshee] Metadata: Do not fetch covers for unknown albums/artists (bgo#619609)

[Gabriel Burt <gburt src gnome org>]

commit cf39de3e4db32fa65ae5810a783d1236128255b5
Author: Benjamín Valero Espinosa <benjavalero gmail com>
Date:   Sat Jul 10 17:17:05 2010 +0200

    Metadata: Do not fetch covers for unknown albums/artists (bgo#619609)
    
    Signed-off-by: Gabriel Burt <gabriel burt gmail com>

 .../Banshee.Metadata/MetadataService.cs            |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/src/Core/Banshee.Services/Banshee.Metadata/MetadataService.cs b/src/Core/Banshee.Services/Banshee.Metadata/MetadataService.cs
index f90f9bf..23e4721 100644
--- a/src/Core/Banshee.Services/Banshee.Metadata/MetadataService.cs
+++ b/src/Core/Banshee.Services/Banshee.Metadata/MetadataService.cs
@@ -84,6 +84,12 @@ namespace Banshee.Metadata
                 return;
             }
 
+            if (String.IsNullOrEmpty (track.AlbumTitle) || track.AlbumTitle == AlbumInfo.UnknownAlbumTitle ||
+                String.IsNullOrEmpty (track.ArtistName) || track.ArtistName == ArtistInfo.UnknownArtistName) {
+                // Do not try to fetch album art for these
+                return;
+            }
+
             lock (((ICollection)queries).SyncRoot) {
                 if (!queries.ContainsKey (track)) {
                     IMetadataLookupJob job = CreateJob (track);