[tracker-miners/wip/carlosg/fix-gstreamer-toc] tracker-extract: Relate contained audio tracks and container file both ways

[Carlos Garnacho <carlosg src gnome org>]

commit d93cbdaad019faa9e3ccdd1fdbf6da904cff1ce1
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sun Mar 31 15:41:11 2019 +0200

    tracker-extract: Relate contained audio tracks and container file both ways
    
    The migration to TrackerResource broke the handling of flac/cue, as
    tracker_resource_print_*() do expect all related resources to be directly
    referenced from the root resource, but the gstreamer extractor just added
    backreferences from the nmm:MusicPieces to the parent nfo:FileDataObject.
    
    Add a relation both ways through nie:hasLogicalPart/nie:isLogicalPartOf
    so the graph is complete, and the tracks referenced from the root element.
    
    Closes: https://gitlab.gnome.org/GNOME/tracker-miners/issues/60

 src/tracker-extract/tracker-extract-gstreamer.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/tracker-extract/tracker-extract-gstreamer.c b/src/tracker-extract/tracker-extract-gstreamer.c
index 3546069a6..0a1563f7c 100644
--- a/src/tracker-extract/tracker-extract-gstreamer.c
+++ b/src/tracker-extract/tracker-extract-gstreamer.c
@@ -892,7 +892,8 @@ extract_metadata (MetadataExtractor      *extractor,
 
                                        track = extract_track (extractor, node->data, file_url, album_disc);
                                        tracker_resource_set_relation (track, "nie:isStoredAs", resource);
-                                       g_object_unref (track);
+                                       tracker_resource_set_relation (track, "nie:isLogicalPartOf", 
resource);
+                                       tracker_resource_add_take_relation (resource, "nie:hasLogicalPart", 
track);
                                }
 
                                tracker_resource_set_string (resource, "nie:url", file_url);