Add instrumentation to track the IceEndpointType.

webrtc/p2p/base/turnport.cc

Index: webrtc/p2p/base/turnport.cc
diff --git a/webrtc/p2p/base/turnport.cc b/webrtc/p2p/base/turnport.cc
index 27f88dc7b8fb61e6380c4ca6465c0773f2a1a336..c1c1ca3b503cd6b7783e820f8c99e97de394398e 100644
--- a/webrtc/p2p/base/turnport.cc
+++ b/webrtc/p2p/base/turnport.cc
@@ -649,11 +649,11 @@ void TurnPort::OnAllocateSuccess(const rtc::SocketAddress& address,
              address,          // Base address.
              related_address,  // Related address.
              UDP_PROTOCOL_NAME,
+             ProtoToString(server_address_.proto),  // The first hop protocol.
              "",  // TCP canddiate type, empty for turn candidates.
              RELAY_PORT_TYPE,
              GetRelayPreference(server_address_.proto, server_address_.secure),
-             server_priority_,
-             true);
+             server_priority_, true);
 }
 
 void TurnPort::OnAllocateError() {