Add remoting::UrlRequest interface with 2 implementations

remoting/base/url_request.h

+// 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.
+
+#ifndef REMOTING_BASE_URL_REQUEST_H_
+#define REMOTING_BASE_URL_REQUEST_H_
+
+#include <string>
+
+#include "base/callback_forward.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace remoting {
+
+// Abstract interface for URL requests.
+class UrlRequest {
+ public:
+  struct Result {
+    Result() = default;
+    Result(int status, std::string response_body)
+        : success(true), status(status), response_body(response_body) {}
+
+    static Result Failed() { return Result(); }
+
+    // Set to true when the URL has been fetched successfully.
+    bool success = false;
+
+    // HTTP status code received from the server. Valid only when |success| is
+    // set to true.
+    int status = 0;
+
+    // Body of the response received from the server. Valid only when |success|
+    // is set to true.
+    std::string response_body;
+  };
+
+  typedef base::Callback<void(const Result& result)> OnResultCallback;
+
+  virtual ~UrlRequest() {}
+
+  // Adds an HTTP header to the request. Has no effect if called after Start().
+  virtual void AddHeader(const std::string& value) = 0;
+
+  // Sends a request to the server. |on_response_callback| will be called to
+  // return result of the request.
+  virtual void Start(const OnResultCallback& on_result_callback) = 0;
+};
+
+// Factory for UrlRequest instances.
+class UrlRequestFactory {
+ public:
+  virtual ~UrlRequestFactory() {}
+  virtual scoped_ptr<UrlRequest> CreateUrlRequest(const std::string& url) = 0;
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_BASE_URL_REQUEST_H_