Various QUIC cleanups to sync with internal code.

net/quic/congestion_control/send_algorithm_interface.cc

Index: net/quic/congestion_control/send_algorithm_interface.cc
diff --git a/net/quic/congestion_control/send_algorithm_interface.cc b/net/quic/congestion_control/send_algorithm_interface.cc
index 493d84e88ef3bf0a24f58b022eebb1787033ac0d..e3452c476597e018cf1bb848ca6474e20c14506b 100644
--- a/net/quic/congestion_control/send_algorithm_interface.cc
+++ b/net/quic/congestion_control/send_algorithm_interface.cc
@@ -5,6 +5,7 @@
 #include "net/quic/congestion_control/send_algorithm_interface.h"
 
 #include "net/quic/congestion_control/fix_rate_sender.h"
+#include "net/quic/congestion_control/inter_arrival_sender.h"
 #include "net/quic/congestion_control/tcp_cubic_sender.h"
 #include "net/quic/quic_protocol.h"
 
@@ -20,7 +21,7 @@ SendAlgorithmInterface* SendAlgorithmInterface::Create(
     case kTCP:
       return new TcpCubicSender(clock, kUseReno, kMaxTcpCongestionWindow);
     case kInterArrival:
-      break;  // TODO(pwestin) Implement.
+      return new InterArrivalSender(clock);
     case kFixRate:
       return new FixRateSender(clock);
   }