Issue summary
Still need to augment the extrinsic to support conditional wrap/unwrap when there is a valid token. We will use the largest T::AssetId to indicate NO unwrapping, i.e.:
- If token is
T::AssetId::MAX() it means ONLY transact.
- If token is 0 it means native unwrapping.
- If token is non-zero it means non-native unwrapping.