Add instrumentation to track the IceEndpointType.

webrtc/p2p/base/stunport_unittest.cc

Index: webrtc/p2p/base/stunport_unittest.cc
diff --git a/webrtc/p2p/base/stunport_unittest.cc b/webrtc/p2p/base/stunport_unittest.cc
index 8b6e81b6d0d7ea2596c6854687358b63e912de82..8897dd4b9876a2e571450b70193527ce57983f15 100644
--- a/webrtc/p2p/base/stunport_unittest.cc
+++ b/webrtc/p2p/base/stunport_unittest.cc
@@ -250,6 +250,7 @@ TEST_F(StunPortTest, TestNoDuplicatedAddressWithTwoStunServers) {
   PrepareAddress();
   EXPECT_TRUE_WAIT(done(), kTimeoutMs);
   EXPECT_EQ(1U, port()->Candidates().size());
+  EXPECT_EQ(port()->Candidates()[0].relay_protocol(), "");
 }
 
 // Test that candidates can be allocated for multiple STUN servers, one of which
@@ -281,4 +282,6 @@ TEST_F(StunPortTest, TestTwoCandidatesWithTwoStunServersAcrossNat) {
   PrepareAddress();
   EXPECT_TRUE_WAIT(done(), kTimeoutMs);
   EXPECT_EQ(2U, port()->Candidates().size());
+  EXPECT_EQ(port()->Candidates()[0].relay_protocol(), "");
+  EXPECT_EQ(port()->Candidates()[1].relay_protocol(), "");
 }