Shopify/active_merchant — pull request #1301 by JDutil (2014-07-11 21:04:16+00:00)
Title: Braintree always charges default card if you pass customer_id.  Change t...

...o payment_method_token in order to allow charging any card. https://developers.braintreepayments.com/ios+ruby/sdk/server/transaction-processing/create-from-vault#customer-id