Include optional.h in rtc_event_log_parser_new.cc

Bug: None
Change-Id: I5ef8227ca4763232717808aae2f6395ce66a4ed9
Reviewed-on: https://webrtc-review.googlesource.com/103160
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24927}
diff --git a/logging/BUILD.gn b/logging/BUILD.gn
index d06578d..3871193 100644
--- a/logging/BUILD.gn
+++ b/logging/BUILD.gn
@@ -288,6 +288,7 @@
       "../rtc_base:protobuf_utils",
       "../rtc_base:rtc_base_approved",
       "//third_party/abseil-cpp/absl/memory",
+      "//third_party/abseil-cpp/absl/types:optional",
     ]
   }