Add logging of host lookups made by TurnPort to the RtcEventLog.

webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h

Index: webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h
diff --git a/webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h b/webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h
index 04aa6bf7f9a856eae990e81034674a80e15a4a06..0b1eaca41f858dca9f276e151057f7c868964d35 100644
--- a/webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h
+++ b/webrtc/logging/rtc_event_log/rtc_event_log_unittest_helper.h
@@ -82,6 +82,9 @@ class RtcEventLogTestHelper {
                                        size_t index,
                                        uint32_t id,
                                        ProbeFailureReason failure_reason);
+
+  static void VerifyLogHostLookupEvent(const ParsedRtcEventLog& parsed_log,
+                                       size_t index);
 };
 
 }  // namespace webrtc