Changed AmazonFlexPay call to fix method_not_found

app/controllers/preorder_controller.rb

@@ -24,15 +24,13 @@ def prefill
     # This is where all the magic happens. We create a multi-use token with Amazon, letting us charge the user's Amazon account
     # Then, if they confirm the payment, Amazon POSTs us their shipping details and phone number
     # From there, we save it, and voila, we got ourselves a preorder!
-    @pipeline = AmazonFlexPay.multi_use_pipeline(@order.uuid,
+    port = Rails.env.production? ? "" : ":3000"
+    callback_url = "#{request.scheme}://#{request.host}#{port}/preorder/postfill"
+    redirect_to AmazonFlexPay.multi_use_pipeline(@order.uuid, callback_url,
                                                  :transaction_amount => price,
                                                  :global_amount_limit => price + Settings.charge_limit,
                                                  :collect_shipping_address => "True",
                                                  :payment_reason => Settings.payment_description)
-
-
-    port = Rails.env.production? ? "" : ":3000"
-    redirect_to @pipeline.url("#{request.scheme}://#{request.host}#{port}/preorder/postfill")
   end
 
   def postfill