[beast] BSE: use ProjectImpl.create_song() instead of an old purged procedure

[Tim Janik <timj src gnome org>]

commit 64d24fda9b056a5880f9838e5c95f7c456d22118
Author: Tim Janik <timj gnu org>
Date:   Sun Dec 4 14:47:22 2016 +0100

    BSE: use ProjectImpl.create_song() instead of an old purged procedure
    
    Signed-off-by: Tim Janik <timj gnu org>

 bse/bseproject.cc |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)
---
diff --git a/bse/bseproject.cc b/bse/bseproject.cc
index ef9d37f..52c1b43 100644
--- a/bse/bseproject.cc
+++ b/bse/bseproject.cc
@@ -1138,9 +1138,8 @@ ProjectImpl::import_midi_file (const String &file_name)
       BseSong *song = bse_project_get_song (self);
       if (!song)
        {
-         gchar *basename = g_path_get_basename (file_name.c_str());
-         bse_item_exec (self, "create-song", basename, &song);
-         g_free (basename);
+          SongIfaceP song_iface = create_song (Path::basename (file_name));
+          song = song_iface->as<BseSong*>();
        }
       bse_midi_file_setup_song (smf, song);
       bse_item_undo_close (ustack);