@Override
    public void cloneFields(Cloner cloner, Object original) {
        AnimTrack[] newTracks = new AnimTrack[tracks.length];
        for (int i = 0; i < tracks.length; i++) {
            newTracks[i] = (cloner.clone(tracks[i]));
        }
        this.tracks = newTracks;
    }
Callback from {@link com.jme3.util.clone.Cloner} to convert this
shallow-cloned clip into a deep-cloned one, using the specified Cloner
and original to resolve copied fields.

@param cloner the Cloner that's cloning this clip (not null)
@param original the instance from which this clip was shallow-cloned (not
null, unaffected)
jme3-core/src/main/java/com/jme3/anim/AnimClip.java