face: replace EventEmitter usage with Signal

refs #2300

Change-Id: I17d0d65d2c474b17dd9f23f271a6144b0b4fbc07
diff --git a/daemon/face/face.hpp b/daemon/face/face.hpp
index 40a77a1..156a82d 100644
--- a/daemon/face/face.hpp
+++ b/daemon/face/face.hpp
@@ -78,19 +78,19 @@
   ~Face();
 
   /// fires when an Interest is received
-  EventEmitter<Interest> onReceiveInterest;
+  signal::Signal<Face, Interest> onReceiveInterest;
 
   /// fires when a Data is received
-  EventEmitter<Data> onReceiveData;
+  signal::Signal<Face, Data> onReceiveData;
 
   /// fires when an Interest is sent out
-  EventEmitter<Interest> onSendInterest;
+  signal::Signal<Face, Interest> onSendInterest;
 
   /// fires when a Data is sent out
-  EventEmitter<Data> onSendData;
+  signal::Signal<Face, Data> onSendData;
 
   /// fires when face disconnects or fails to perform properly
-  EventEmitter<std::string/*reason*/> onFail;
+  signal::Signal<Face, std::string/*reason*/> onFail;
 
   /// send an Interest
   virtual void
@@ -187,6 +187,11 @@
   void
   fail(const std::string& reason);
 
+  DECLARE_SIGNAL_EMIT(onReceiveInterest)
+  DECLARE_SIGNAL_EMIT(onReceiveData)
+  DECLARE_SIGNAL_EMIT(onSendInterest)
+  DECLARE_SIGNAL_EMIT(onSendData)
+
 private:
   void
   setId(FaceId faceId);