[Cast] Fix log_deserializer BasePacketEvent merge bug.

media/cast/logging/log_deserializer.cc

Index: media/cast/logging/log_deserializer.cc
diff --git a/media/cast/logging/log_deserializer.cc b/media/cast/logging/log_deserializer.cc
index a4c79b3de950bef74568ab7c220525c0509989d5..1c6dd572240d61df1d70351227236856ec753fbe 100644
--- a/media/cast/logging/log_deserializer.cc
+++ b/media/cast/logging/log_deserializer.cc
@@ -35,7 +35,12 @@ void MergePacketEvent(const AggregatedPacketEvent& from,
     for (int j = 0; j < to->base_packet_event_size(); j++) {
       BasePacketEvent* to_base_event = to->mutable_base_packet_event(j);
       if (from_base_event.packet_id() == to_base_event->packet_id()) {
+        int packet_size = std::max(
+            from_base_event.size(), to_base_event->size());
+        // Need special merge logic here because we need to prevent a valid
+        // packet size (> 0) from being overwritten with an invalid one (= 0).
         to_base_event->MergeFrom(from_base_event);
+        to_base_event->set_size(packet_size);
         merged = true;
         break;
       }