Move the logic from SendAlgorithmInterface::RetransmissionDelay() into QuicSentPacketManager, becau…

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 89a1dc5ffa23bff721d4264aed7cb9ed18a9b8b5..c38db4c754877cab3dfe28698576ab3faa1016e1 100644
--- a/net/quic/core/quic_sent_packet_manager.cc
+++ b/net/quic/core/quic_sent_packet_manager.cc
@@ -859,14 +859,18 @@ const QuicTime::Delta QuicSentPacketManager::GetTailLossProbeDelay() const {
 }
 
 const QuicTime::Delta QuicSentPacketManager::GetRetransmissionDelay() const {
-  QuicTime::Delta retransmission_delay = send_algorithm_->RetransmissionDelay();
-  if (retransmission_delay.IsZero()) {
+  QuicTime::Delta retransmission_delay = QuicTime::Delta::Zero();
+  if (rtt_stats_.smoothed_rtt().IsZero()) {
     // We are in the initial state, use default timeout values.
     retransmission_delay =
         QuicTime::Delta::FromMilliseconds(kDefaultRetransmissionTimeMs);
-  } else if (retransmission_delay.ToMilliseconds() < kMinRetransmissionTimeMs) {
+  } else {
     retransmission_delay =
-        QuicTime::Delta::FromMilliseconds(kMinRetransmissionTimeMs);
+        rtt_stats_.smoothed_rtt() + 4 * rtt_stats_.mean_deviation();
+    if (retransmission_delay.ToMilliseconds() < kMinRetransmissionTimeMs) {
+      retransmission_delay =
+          QuicTime::Delta::FromMilliseconds(kMinRetransmissionTimeMs);
+    }
   }
 
   // Calculate exponential back off.
@@ -958,7 +962,6 @@ void QuicSentPacketManager::OnConnectionMigration(QuicPathId,
   send_algorithm_->OnConnectionMigration();
 }
 
-
 void QuicSentPacketManager::SetDebugDelegate(DebugDelegate* debug_delegate) {
   debug_delegate_ = debug_delegate;
 }