replay: only keep one init_data in merged events (#26863)

don't merge init_data
old-commit-hash: b5a2dfa93e

tools/replay/replay.cc

@@ -269,9 +269,13 @@ void Replay::mergeSegments(const SegmentMap::iterator &begin, const SegmentMap::
     new_events_->reserve(new_events_size);
     for (int n : segments_need_merge) {
       const auto &e = segments_[n]->log->events;
-      auto middle = new_events_->insert(new_events_->end(), e.begin(), e.end());
+      if (e.size() > 0) {
+        auto insert_from = e.begin();
+        if (new_events_->size() > 0 && (*insert_from)->which == cereal::Event::Which::INIT_DATA) ++insert_from;
+        auto middle = new_events_->insert(new_events_->end(), insert_from, e.end());
         std::inplace_merge(new_events_->begin(), middle, new_events_->end(), Event::lessThan());
       }
+    }
 
     updateEvents([&]() {
       events_.swap(new_events_);