Fixed default version in PackTrack when nothing happens

Event/EventPacker/src/component/PackTrack.cpp

@@ -48,12 +48,12 @@ namespace LHCb {
 DECLARE_COMPONENT_WITH_ID( LHCb::PackTrack, "PackTrack" )
 
 LHCb::PackedTracks LHCb::PackTrack::operator()() const {
-  if ( !m_tracks.exist() ) return {};
-  auto const* tracks = m_tracks.get();
-
   PackedTracks out;
   out.setVersion( 5 );
 
+  if ( !m_tracks.exist() ) return out;
+  auto const* tracks = m_tracks.get();
+
   // Pack the tracks
   const TrackPacker packer( this );
   packer.pack( *tracks, out );