[Payments] Refactor into PaymentRequestState and Spec

components/payments/content/payment_request_spec.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_CONTENT_PAYMENT_REQUEST_SPEC_H_
+#define COMPONENTS_PAYMENTS_CONTENT_PAYMENT_REQUEST_SPEC_H_
+
+#include <string>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "components/payments/content/payment_request.mojom.h"
+
+namespace payments {
+
+class PaymentRequestSpec {

[please use gerrit instead, 2017/03/14 16:35:21]

Please add a comment for the purpose of this class.

[Mathieu, 2017/03/14 18:05:39]

Done.

+ public:
+  class Observer {
+   public:
+    // Called when the provided spec (details, options, method_data) is invalid.
+    virtual void OnInvalidSpecProvided() = 0;
+
+   protected:
+    virtual ~Observer() {}
+  };
+
+  PaymentRequestSpec(
+      mojom::PaymentOptionsPtr options,
+      mojom::PaymentDetailsPtr details,
+      const std::vector<mojom::PaymentMethodDataPtr>& method_data,
+      PaymentRequestSpec::Observer* observer);
+  ~PaymentRequestSpec();
+
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  bool request_shipping() const { return options_->request_shipping; }
+  bool request_payer_name() const { return options_->request_payer_name; }
+  bool request_payer_phone() const { return options_->request_payer_phone; }
+  bool request_payer_email() const { return options_->request_payer_email; }
+
+  const std::vector<std::string>& supported_card_networks() {
+    return supported_card_networks_;
+  }
+
+  mojom::PaymentDetails* details() { return details_.get(); }

[please use gerrit instead, 2017/03/14 16:35:21]

From what I understand, details() and options() should be read-only, so let's
try to use const-ref for return parameter and make the method const as well.

[Mathieu, 2017/03/14 18:05:39]

Done.

+  mojom::PaymentOptions* options() { return options_.get(); }
+
+ private:
+  // Validates the |method_data| and fills |supported_card_networks_|.
+  void PopulateValidatedMethodData(
+      const std::vector<mojom::PaymentMethodDataPtr>& method_data);
+
+  // Will notify all observers that the spec is invalid.
+  void NotifyOnInvalidSpecProvided();
+
+  mojom::PaymentOptionsPtr options_;
+  mojom::PaymentDetailsPtr details_;
+
+  // A list of supported basic card networks, in order that they were specified
+  // by the merchant.
+  std::vector<std::string> supported_card_networks_;
+
+  base::ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(PaymentRequestSpec);
+};
+
+}  // namespace payments
+
+#endif  // COMPONENTS_PAYMENTS_CONTENT_PAYMENT_REQUEST_SPEC_H_