PaymentRequest: Implement PaymentDetailsModifier dictionary (in blink side).

third_party/WebKit/public/platform/modules/payments/payment_request.mojom

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 [JavaPackage="org.chromium.mojom.payments"]
 module blink.mojom;
 
 // The shipping address that the browser process provides to the renderer
 // process. Built either by the browser or a payment app.
 struct PaymentAddress {
@@ skipping 66 matching lines @@
   PaymentCurrencyAmount amount;
 };
 
 struct PaymentShippingOption {
   string id;
   string label;
   PaymentCurrencyAmount amount;
   bool selected;
 };
 
+struct PaymentDetailsModifier {
+  array<string> supported_methods;
+  PaymentItem total;
+  array<PaymentItem> additional_display_items;
+};
+
 struct PaymentDetails {
   PaymentItem total;
   array<PaymentItem> display_items;
   array<PaymentShippingOption> shipping_options;
+  array<PaymentDetailsModifier> modifiers;
 };
 
 struct PaymentOptions {
   bool request_payer_email;
   bool request_payer_phone;
   bool request_shipping;
 };
 
 struct PaymentMethodData {
   array<string> supported_methods;
@@ skipping 17 matching lines @@
 
 interface PaymentRequest {
   SetClient(PaymentRequestClient client);
   Show(array<PaymentMethodData> methodData,
        PaymentDetails details,
        PaymentOptions options);
   UpdateWith(PaymentDetails details);
   Abort();
   Complete(PaymentComplete result);
 };