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

webrtc/logging/rtc_event_log/rtc_event_log_parser.cc

Index: webrtc/logging/rtc_event_log/rtc_event_log_parser.cc
diff --git a/webrtc/logging/rtc_event_log/rtc_event_log_parser.cc b/webrtc/logging/rtc_event_log/rtc_event_log_parser.cc
index a7237ee8511507228ee026a08e7440f522138976..7b8af9a0671ad4d281196359fa7a28d2d74e0191 100644
--- a/webrtc/logging/rtc_event_log/rtc_event_log_parser.cc
+++ b/webrtc/logging/rtc_event_log/rtc_event_log_parser.cc
@@ -74,6 +74,8 @@ ParsedRtcEventLog::EventType GetRuntimeEventType(
       return ParsedRtcEventLog::EventType::BWE_PROBE_CLUSTER_CREATED_EVENT;
     case rtclog::Event::BWE_PROBE_RESULT_EVENT:
       return ParsedRtcEventLog::EventType::BWE_PROBE_RESULT_EVENT;
+    case rtclog::Event::HOST_LOOKUP_EVENT:
+      return ParsedRtcEventLog::EventType::HOST_LOOKUP_EVENT;
   }
   RTC_NOTREACHED();
   return ParsedRtcEventLog::EventType::UNKNOWN_EVENT;
@@ -654,4 +656,19 @@ ParsedRtcEventLog::MediaType ParsedRtcEventLog::GetMediaType(
   }
   return MediaType::ANY;
 }
+
+void ParsedRtcEventLog::GetHostLookup(
+    size_t index,
+    int* error, int64_t* host_lookup_time_ms) const {
+  RTC_CHECK_LT(index, GetNumberOfEvents());
+  const rtclog::Event& event = events_[index];
+  RTC_CHECK(event.has_type());
+  RTC_CHECK_EQ(event.type(), rtclog::Event::HOST_LOOKUP_EVENT);
+  RTC_CHECK(event.has_host_lookup_result());
+  const rtclog::HostLookupResult& lookup_event = event.host_lookup_result();
+  RTC_CHECK(lookup_event.has_error());
+  *error = lookup_event.error();

[terelius, 2017/08/21 09:38:14]

We have previously allowed passing in nullptr if we're not interested in
particular field. I suggest changing to
if (error)
  *error = lookup_event.error();

+  RTC_CHECK(lookup_event.has_host_lookup_time_ms());
+  *host_lookup_time_ms = lookup_event.host_lookup_time_ms();

[terelius, 2017/08/21 09:38:14]

Same here.

+}
 }  // namespace webrtc