- We extract some code logic to methods to allow to override them.
This is needed for the subscription module where a payment token need
to be copied from a transaction to a subscription.
The subscriptions is created from a sale order and before the
payment.transaction holding the payment.token id is validated.
Since the payment.transaction is not validated, the subscription
module doesn't find the correct transaction.
By extracting this code logic, we can override exactly when it should
be.