Replace inconsistent log_segments() function in RTC event log parser

Bug: webrtc:11566
Change-Id: I739bbc29ae5423f3fedcc08e991e27fa0af840c5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/176081
Commit-Queue: Björn Terelius <terelius@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#31371}
diff --git a/rtc_tools/rtc_event_log_visualizer/alerts.cc b/rtc_tools/rtc_event_log_visualizer/alerts.cc
index f2d9564..86372de 100644
--- a/rtc_tools/rtc_event_log_visualizer/alerts.cc
+++ b/rtc_tools/rtc_event_log_visualizer/alerts.cc
@@ -62,10 +62,7 @@
       direction == kIncomingPacket ? TriageAlertType::kIncomingCaptureTimeJump
                                    : TriageAlertType::kOutgoingCaptureTimeJump;
 
-  const int64_t segment_end_us =
-      parsed_log.log_segments().empty()
-          ? std::numeric_limits<int64_t>::max()
-          : parsed_log.log_segments().front().stop_time_us();
+  const int64_t segment_end_us = parsed_log.first_log_segment().stop_time_us();
 
   // Check for gaps in sequence numbers and capture timestamps.
   for (const auto& stream : parsed_log.rtp_packets_by_ssrc(direction)) {
@@ -133,10 +130,7 @@
                                    ? TriageAlertType::kIncomingRtcpGap
                                    : TriageAlertType::kOutgoingRtcpGap;
 
-  const int64_t segment_end_us =
-      parsed_log.log_segments().empty()
-          ? std::numeric_limits<int64_t>::max()
-          : parsed_log.log_segments().front().stop_time_us();
+  const int64_t segment_end_us = parsed_log.first_log_segment().stop_time_us();
 
   // TODO(terelius): The parser could provide a list of all packets, ordered
   // by time, for each direction.
@@ -202,10 +196,7 @@
   AnalyzeTransmissionGaps(parsed_log, kIncomingPacket);
   AnalyzeTransmissionGaps(parsed_log, kOutgoingPacket);
 
-  const int64_t segment_end_us =
-      parsed_log.log_segments().empty()
-          ? std::numeric_limits<int64_t>::max()
-          : parsed_log.log_segments().front().stop_time_us();
+  const int64_t segment_end_us = parsed_log.first_log_segment().stop_time_us();
 
   int64_t first_occurrence = parsed_log.last_timestamp();
   constexpr double kMaxLossFraction = 0.05;