[Chromoting] Use HostExperimentSessionPlugin in host

remoting/protocol/fake_session.h

Index: remoting/protocol/fake_session.h
diff --git a/remoting/protocol/fake_session.h b/remoting/protocol/fake_session.h
index 7d31c9c064fc61f63987cd9c47e010a512cf90b6..6100136ff7822b5eee4324f3e103b6c2f383e9d7 100644
--- a/remoting/protocol/fake_session.h
+++ b/remoting/protocol/fake_session.h
@@ -5,6 +5,7 @@
 #ifndef REMOTING_PROTOCOL_FAKE_SESSION_H_
 #define REMOTING_PROTOCOL_FAKE_SESSION_H_
 
+#include <deque>
 #include <map>
 #include <memory>
 #include <string>
@@ -14,6 +15,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "remoting/protocol/fake_stream_socket.h"
+#include "remoting/protocol/jingle_messages.h"
 #include "remoting/protocol/session.h"
 #include "remoting/protocol/transport.h"
 
@@ -40,6 +42,11 @@ class FakeSession : public Session {
     signaling_delay_ = signaling_delay;
   }
 
+  // Adds an |attachment| to |round|, which will be sent to plugins added by
+  // AddPlugin() function.
+  void SetAttachment(size_t round,
+                     std::unique_ptr<buzz::XmlElement> attachment);
+
   // Session interface.
   void SetEventHandler(EventHandler* event_handler) override;
   ErrorCode error() override;
@@ -70,6 +77,8 @@ class FakeSession : public Session {
   base::WeakPtr<FakeSession> peer_;
   base::TimeDelta signaling_delay_;
 
+  std::deque<JingleMessage> attachments_;
+
   base::WeakPtrFactory<FakeSession> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeSession);