[Payments] Support canMakePayment on Desktop

components/payments/content/payment_request_state.cc

 // 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.
 
 #include "components/payments/content/payment_request_state.h"
 
 #include <set>
 
 #include "components/autofill/core/browser/autofill_data_util.h"
 #include "components/autofill/core/browser/autofill_profile.h"
@@ skipping 16 matching lines @@
       personal_data_manager_(personal_data_manager),
       selected_shipping_profile_(nullptr),
       selected_contact_profile_(nullptr),
       selected_instrument_(nullptr),
       selected_shipping_option_(nullptr) {
   PopulateProfileCache();
   UpdateSelectedShippingOption();
   SetDefaultProfileSelections();
 }
 
+bool PaymentRequestState::CanMakePayment() {
+  // TODO(crbug.com/704675): Handle incognito mode when replying to this method.
+  for (const std::unique_ptr<PaymentInstrument>& instrument :
+       available_instruments_) {

[please use gerrit instead, 2017/03/24 14:47:25]

Need to filter by valid instruments (instrument->IsValid()).

[Mathieu, 2017/03/24 15:38:40]

Whoops, thanks.

+    if (spec_->supported_card_networks_set().count(
+            instrument.get()->method_name()))
+      return true;
+  }
+  return false;
+}
+
 void PaymentRequestState::AddObserver(Observer* observer) {
   CHECK(observer);
   observers_.AddObserver(observer);
 }
 PaymentRequestState::~PaymentRequestState() {}
 
 void PaymentRequestState::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
 
@@ skipping 173 matching lines @@
       spec_->details().shipping_options.rend(),
       [](const payments::mojom::PaymentShippingOptionPtr& element) {
         return element->selected;
       });
   if (selected_shipping_option_it != spec_->details().shipping_options.rend()) {
     selected_shipping_option_ = selected_shipping_option_it->get();
   }
 }
 
 }  // namespace payments