Support needed to measure user and service traffic in Chrome.

components/data_use_measurement/content/data_use_user_data.h

+// Copyright (c) 2015 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_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_USER_DATA_H_

[sclittle, 2015/08/21 23:55:34]

This file and it's .cc file should be in "data_use_measurement/core/", not
content.

[amohammadkhan, 2015/08/26 22:28:40]

Done.

+#define COMPONENTS_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_USER_DATA_H_
+
+#include <string>
+
+#include "base/supports_user_data.h"
+
+namespace data_use_measurement {
+// Used to annotate URLRequests with the service name if the URLRequest is used
+// by a service.
+class DataUseUserData : public base::SupportsUserData::Data {
+ public:
+  explicit DataUseUserData(std::string service_name);
+  ~DataUseUserData() override;
+
+  std::string service_name() const { return service_name_; }
+
+  static const void* kUserDataKey;
+
+ private:
+  std::string service_name_;

[sclittle, 2015/08/21 23:55:34]

Instead of holding a string, could you create an enum in this file of all the
services, and just store the enum value in the DataUseUserData?

[amohammadkhan, 2015/08/24 23:18:47]

You are right. We had a problem about a good place for storing the enum in
previous architecture and using the hash of service name was used then, but now
it seems we do not have this problem anymore so we can use the enum.

+};
+base::SupportsUserData::Data* CreateDataUseUserData(std::string service_name);
+} // data_use_measurement namespace
+#endif  // COMPONENTS_DATA_USE_MEASUREMENT_CONTENT_DATA_USE_USER_DATA_H_