[Payments] Support canMakePayment on Desktop

components/payments/content/payment_request_state.cc

Index: components/payments/content/payment_request_state.cc
diff --git a/components/payments/content/payment_request_state.cc b/components/payments/content/payment_request_state.cc
index 26e8bf3d5f951169ceec6af0171c6db8a08d4eee..15f22e03a452df3c0edb053db874bf288a401f94 100644
--- a/components/payments/content/payment_request_state.cc
+++ b/components/payments/content/payment_request_state.cc
@@ -34,6 +34,17 @@ PaymentRequestState::PaymentRequestState(
   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);