[NTP::Push] Add the classes for sending a breaking news subscription request

components/ntp_snippets/breaking_news/subscription_request_params.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_NTP_SNIPPETS_BREAKING_NEWS_SUBSCRIPTION_REQUEST_PARAMS_H_
+#define COMPONENTS_NTP_SNIPPETS_BREAKING_NEWS_SUBSCRIPTION_REQUEST_PARAMS_H_
+
+#include <memory>
+#include <set>
+#include <string>
+
+#include "base/callback.h"
+#include "base/optional.h"
+#include "base/values.h"
+#include "components/ntp_snippets/category.h"
+
+namespace ntp_snippets {
+
+// Contains all parameters for subscribing for breaking news push messages.
+struct SubscriptionRequestParams {

[fhorschig, 2017/05/31 14:51:14]

that is a very, very, very simple class.
are you sure we need it at all?
It seems like we could inline the parameters as builder setters.
(The original class used more difficult param construction and had to
handle the outcome based on the result .... which we don't even parse here.)

[mamir, 2017/05/31 18:46:04]

Done.

+  SubscriptionRequestParams();
+  SubscriptionRequestParams(const SubscriptionRequestParams&);
+  ~SubscriptionRequestParams();
+
+  // GCM subscribtion token obtain from GCM driver (instanceID::getToken())
+  std::string token;
+
+  // TODO(mamir): Additional fields to be added: country, language.

[fhorschig, 2017/05/31 14:51:14]

All these fields look easy enough to add as a Set{Country,Language,...}
into the builder.

[mamir, 2017/05/31 18:46:04]

Acknowledged.

+};
+
+// Callbacks for JSON parsing to allow injecting platform-dependent code.

[fhorschig, 2017/05/31 14:51:14]

None of which are actually used.

[mamir, 2017/05/31 18:46:04]

Acknowledged.

+using SuccessCallback =
+    base::Callback<void(std::unique_ptr<base::Value> result)>;
+using ErrorCallback = base::Callback<void(const std::string& error)>;
+using ParseJSONCallback =
+    base::Callback<void(const std::string& raw_json_string,
+                        const SuccessCallback& success_callback,
+                        const ErrorCallback& error_callback)>;
+
+}  // namespace ntp_snippets
+
+#endif  // COMPONENTS_NTP_SNIPPETS_BREAKING_NEWS_SUBSCRIPTION_REQUEST_PARAMS_H_