face: implement close-on-idle and persistency change for Ethernet unicast

Change-Id: I255024990a72b8cea5a44fa89f515ad91aadba66
Refs: #4011
diff --git a/daemon/face/websocket-transport.cpp b/daemon/face/websocket-transport.cpp
index 68fd08a..d4bbbac 100644
--- a/daemon/face/websocket-transport.cpp
+++ b/daemon/face/websocket-transport.cpp
@@ -117,13 +117,13 @@
 {
   NFD_LOG_FACE_TRACE(__func__);
 
-  ++this->nOutPings;
-
   websocketpp::lib::error_code error;
   m_server.ping(m_handle, "NFD-WebSocket", error);
   if (error)
     return processErrorCode(error);
 
+  ++this->nOutPings;
+
   this->schedulePing();
 }
 
@@ -138,7 +138,7 @@
 void
 WebSocketTransport::handlePongTimeout()
 {
-  NFD_LOG_FACE_WARN(__func__);
+  NFD_LOG_FACE_ERROR("Pong timeout");
   this->setState(TransportState::FAILED);
   doClose();
 }
@@ -154,8 +154,7 @@
     // transport is shutting down, ignore any errors
     return;
 
-  NFD_LOG_FACE_WARN("Send or ping operation failed: " << error.message());
-
+  NFD_LOG_FACE_ERROR("Send or ping operation failed: " << error.message());
   this->setState(TransportState::FAILED);
   doClose();
 }