Fix all Performance and Bug-Prone patterns in quic/core. No functional change. Not flag protected.

net/quic/core/quic_sent_packet_manager.cc

Index: net/quic/core/quic_sent_packet_manager.cc
diff --git a/net/quic/core/quic_sent_packet_manager.cc b/net/quic/core/quic_sent_packet_manager.cc
index 8cb4117a99a335c12fd47f7259d3e36f68c629a7..c70da4477989100820201294e48351c0fd86682b 100644
--- a/net/quic/core/quic_sent_packet_manager.cc
+++ b/net/quic/core/quic_sent_packet_manager.cc
@@ -705,7 +705,7 @@ void QuicSentPacketManager::InvokeLossDetection(QuicTime time) {
   }
   loss_algorithm_->DetectLosses(unacked_packets_, time, rtt_stats_,
                                 largest_newly_acked_, &packets_lost_);
-  for (const pair<QuicPacketNumber, QuicByteCount>& pair : packets_lost_) {
+  for (const auto& pair : packets_lost_) {
     ++stats_->packets_lost;
     if (debug_delegate_ != nullptr) {
       debug_delegate_->OnPacketLoss(pair.first, LOSS_RETRANSMISSION, time);