[Chromoting] Add SessionPlugin in JingleSession

remoting/protocol/jingle_session.h

Index: remoting/protocol/jingle_session.h
diff --git a/remoting/protocol/jingle_session.h b/remoting/protocol/jingle_session.h
index 9efd42e21e5ec1527effb570c451df4f9c59b8a5..e8798acbfa3aa6363d1638ba398e08d5e327463c 100644
--- a/remoting/protocol/jingle_session.h
+++ b/remoting/protocol/jingle_session.h
@@ -43,6 +43,7 @@ class JingleSession : public Session {
   const SessionConfig& config() override;
   void SetTransport(Transport* transport) override;
   void Close(protocol::ErrorCode error) override;
+  void Attach(std::unique_ptr<SessionPlugin> plugin) override;
 
  private:
   friend class JingleSessionManager;
@@ -119,6 +120,12 @@ class JingleSession : public Session {
   // Returns true if the state of the session is not CLOSED or FAILED
   bool is_session_active();
 
+  // Executes all plugins against incoming JingleMessage.
+  void ExecutePluginsOnIncomingMessage(const JingleMessage& message);
+
+  // Executes all plugins against outgoing JingleMessage.
+  void ExecutePluginsOnOutgoingMessage(JingleMessage* message);
+
   // Returns the value of the ID attribute of the next outgoing set IQ with the
   // sequence ID encoded.
   std::string GetNextOutgoingId();
@@ -169,6 +176,9 @@ class JingleSession : public Session {
   // authenticated.
   std::vector<PendingMessage> pending_transport_info_;
 
+  // The SessionPlugins attached to this session.
+  std::vector<std::unique_ptr<SessionPlugin>> plugins_;
+
   base::WeakPtrFactory<JingleSession> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(JingleSession);