Simplify RTO interaction between the QUIC sent packet manager and the

net/quic/congestion_control/tcp_cubic_sender_test.cc

Index: net/quic/congestion_control/tcp_cubic_sender_test.cc
diff --git a/net/quic/congestion_control/tcp_cubic_sender_test.cc b/net/quic/congestion_control/tcp_cubic_sender_test.cc
index 20dd6a6d31659d83283cc5b28e1b89d191c9e2af..40eb28d64b6dc0503d9310faec11715e5ae4247b 100644
--- a/net/quic/congestion_control/tcp_cubic_sender_test.cc
+++ b/net/quic/congestion_control/tcp_cubic_sender_test.cc
@@ -240,10 +240,19 @@ TEST_F(TcpCubicSenderTest, RTOCongestionWindow) {
   EXPECT_EQ(kDefaultWindowTCP, sender_->SendWindow());
 
   // Expect the window to decrease to the minimum once the RTO fires.
-  sender_->OnRetransmissionTimeout();
+  sender_->OnRetransmissionTimeout(true);
   EXPECT_EQ(2 * kDefaultTCPMSS, sender_->SendWindow());
 }
 
+TEST_F(TcpCubicSenderTest, RTOCongestionWindowNoRetransmission) {
+  EXPECT_EQ(kDefaultWindowTCP, sender_->SendWindow());
+
+  // Expect the window to remain unchanged if the RTO fires but no
+  // packets are retransmitted.
+  sender_->OnRetransmissionTimeout(false);
+  EXPECT_EQ(kDefaultWindowTCP, sender_->SendWindow());
+}
+
 TEST_F(TcpCubicSenderTest, RetransmissionDelay) {
   const int64 kRttMs = 10;
   const int64 kDeviationMs = 3;