Add canMakeActivePayment() method to web payments.

components/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.payments.mojom"]
 module payments.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 59 matching lines @@
   string? payer_email;
   string? payer_phone;
 };
 
 enum PaymentErrorReason {
   UNKNOWN,
   USER_CANCEL,
   NOT_SUPPORTED
 };
 
+enum ActivePaymentQueryResult {
+  CAN_MAKE_ACTIVE_PAYMENT,
+  CANNOT_MAKE_ACTIVE_PAYMENT,
+  QUERY_QUOTA_EXCEEDED
+};
+
 interface PaymentRequestClient {
   OnShippingAddressChange(PaymentAddress address);
   OnShippingOptionChange(string shipping_option_id);
   OnPaymentResponse(PaymentResponse response);
   OnError(PaymentErrorReason error);
   OnComplete();
   OnAbort(bool aborted_successfully);
+  OnCanMakeActivePayment(ActivePaymentQueryResult result);
 };
 
 struct PaymentItem {
   string label;
   PaymentCurrencyAmount amount;
   bool pending;
 };
 
 struct PaymentShippingOption {
   string id;
@@ skipping 52 matching lines @@
 
 interface PaymentRequest {
   Init(PaymentRequestClient client,
        array<PaymentMethodData> methodData,
        PaymentDetails details,
        PaymentOptions options);
   Show();
   UpdateWith(PaymentDetails details);
   Abort();
   Complete(PaymentComplete result);
+  CanMakeActivePayment();

[Marijn Kruisselbrink, 2016/11/11 00:00:05]

Would it make sense to make this CanMakeActivePayment() =>
(ActivePaymentQueryResult result), rather than sending the result through a
separate method in PaymentRequestClient? Although I guess the separate method
thing also makes sense since it's the same pattern the existing code uses.

[please use gerrit instead, 2016/11/11 21:11:50]

I'd prefer to stick to the pre-existing pattern in this file.

 };