Fix missing return value(2)

Bug: webrtc:11933
Change-Id: I6cceedbfa824b8e24f90219397735e767554915e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/234741
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35174}
diff --git a/logging/rtc_event_log/events/rtc_event_field_encoding.cc b/logging/rtc_event_log/events/rtc_event_field_encoding.cc
index db407ff..23aa308 100644
--- a/logging/rtc_event_log/events/rtc_event_field_encoding.cc
+++ b/logging/rtc_event_log/events/rtc_event_field_encoding.cc
@@ -79,6 +79,8 @@
       RTC_NOTREACHED();
       return std::string();
   }
+  RTC_NOTREACHED();
+  return std::string();
 }
 
 absl::optional<FieldType> ConvertFieldType(uint64_t value) {