@Override
    public <T> void registerAssetClone(AssetKey<T> key, T clone) {
        ArrayList<AssetKey> loadStack = assetLoadStack.get();
        ((CloneableSmartAsset) clone).setKey(loadStack.remove(loadStack.size() - 1));
    }
Stores the original key and original asset.
The asset info contains a cloneable asset (e.g. the original, from
which all clones are made) and also a weak reference to the
original key, which is used when the clones are produced.
jme3-core/src/main/java/com/jme3/asset/cache/WeakRefCloneAssetCache.java