PaymentCurrencyAmount.currencySystem removed from spec
diff --git a/interfaces/payment-request.idl b/interfaces/payment-request.idl
index 50a5dea..f925db2 100644
--- a/interfaces/payment-request.idl
+++ b/interfaces/payment-request.idl
@@ -27,8 +27,6 @@
 dictionary PaymentCurrencyAmount {
   required DOMString currency;
   required DOMString value;
-  // Note: currencySystem is "at risk" of being removed!
-  DOMString currencySystem = "urn:iso:std:iso:4217";
 };
 
 dictionary PaymentDetailsBase {