[Chromoting] Implement HostExperimentSessionPlugin

remoting/protocol/host_experiment_session_plugin.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_PROTOCOL_HOST_EXPERIMENT_SESSION_PLUGIN_H_
+#define REMOTING_PROTOCOL_HOST_EXPERIMENT_SESSION_PLUGIN_H_
+
+#include <memory>
+#include <string>
+
+#include "remoting/protocol/jingle_messages.h"
+#include "remoting/protocol/session.h"
+#include "remoting/protocol/session_plugin.h"
+#include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
+
+namespace remoting {
+namespace protocol {
+
+// A SessionPlugin implementation to send host attributes to client, and
+// receives experiment settings. This plugin is for host only.
+class HostExperimentSessionPlugin : public SessionPlugin {
+ public:
+  using SessionPlugin::SessionPlugin;
+
+  void OnSending(Session::State state,
+                 JingleMessage::ActionType action,
+                 std::unique_ptr<buzz::XmlElement>* attachments) override;
+
+  void OnReceiving(
+      Session::State state,
+      JingleMessage::ActionType action,
+      const std::unique_ptr<buzz::XmlElement>& attachments) override;
+
+  // The configuration sent from client, may be empty.
+  const std::string& configuration() const;
+
+ private:
+  std::string configuration_;
+};
+
+}  // namespace protocol
+}  // namespace remoting
+
+#endif  // REMOTING_PROTOCOL_HOST_EXPERIMENT_SESSION_PLUGIN_H_