[Payments] Return a basic card response

components/payments/core/payment_instrument.h

+// Copyright 2017 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.
+
+#ifndef COMPONENTS_PAYMENTS_CORE_PAYMENT_INSTRUMENT_H_
+#define COMPONENTS_PAYMENTS_CORE_PAYMENT_INSTRUMENT_H_
+
+#include <set>
+#include <string>
+
+#include "base/macros.h"
+
+namespace payments {
+
+// Base class which represents a form of payment in Payment Request.
+class PaymentInstrument {
+ public:
+  class Delegate {
+   public:

[please use gerrit instead, 2017/03/08 14:46:10]

Need an empty virtual destrutor.

[Mathieu, 2017/03/08 18:04:26]

Done.

+    // Should be called with method name (e.g. "visa"), and json-serialized

[please use gerrit instead, 2017/03/08 14:46:10]

Remove comma before "and". Add comma after "e.g.".

[Mathieu, 2017/03/08 18:04:26]

Done.

+    // stringified details.
+    virtual void OnInstrumentDetailsReady(
+        const std::string& method_name,
+        const std::string& stringified_details) = 0;
+
+    virtual void OnInstrumentDetailsError() = 0;
+  };
+
+  virtual ~PaymentInstrument() {}
+
+  // Will call into the |delegate| (can't be null) on success or error.
+  virtual void InvokePaymentApp(Delegate* delegate) = 0;
+
+  const std::string& method_name() { return method_name_; }
+
+ protected:
+  explicit PaymentInstrument(const std::string& method_name)
+      : method_name_(method_name) {}
+
+ private:
+  const std::string method_name_;
+
+  DISALLOW_COPY_AND_ASSIGN(PaymentInstrument);
+};
+
+}  // namespace payments
+
+#endif  // COMPONENTS_PAYMENTS_CORE_PAYMENT_INSTRUMENT_H_