Fixes QUIC's Cubic sender to use correct alpha when in Reno mode.

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 9faecc4432d09967894d8c831b4605cb1f6d41ad..88921bad87eb4eb00284d3a79dd5b25b531b12c2 100644
--- a/net/quic/congestion_control/tcp_cubic_sender_test.cc
+++ b/net/quic/congestion_control/tcp_cubic_sender_test.cc
@@ -498,7 +498,9 @@ TEST_F(TcpCubicSenderTest, TcpRenoMaxCongestionWindow) {
 
 TEST_F(TcpCubicSenderTest, TcpCubicMaxCongestionWindow) {
   const QuicTcpCongestionWindow kMaxCongestionWindowTCP = 50;
-  const int kNumberOfAcks = 1000;
+  // Set to 10000 to compensate for small cubic alpha.
+  const int kNumberOfAcks = 10000;
+
   sender_.reset(
       new TcpCubicSenderPeer(&clock_, false, kMaxCongestionWindowTCP));