Start using the loss timeout in QuicSentPacketManager and add a mock

net/quic/test_tools/quic_test_utils.h

Index: net/quic/test_tools/quic_test_utils.h
diff --git a/net/quic/test_tools/quic_test_utils.h b/net/quic/test_tools/quic_test_utils.h
index ffe3b13ac37f58f451401bcf0b706b8d5dfc8c95..eec32075b7bee2fe0d18c7fedb10a1ebb9f53a0b 100644
--- a/net/quic/test_tools/quic_test_utils.h
+++ b/net/quic/test_tools/quic_test_utils.h
@@ -11,6 +11,7 @@
 #include <vector>
 
 #include "base/strings/string_piece.h"
+#include "net/quic/congestion_control/loss_detection_interface.h"
 #include "net/quic/congestion_control/send_algorithm_interface.h"
 #include "net/quic/quic_ack_notifier.h"
 #include "net/quic/quic_connection.h"
@@ -437,6 +438,19 @@ class MockSendAlgorithm : public SendAlgorithmInterface {
   DISALLOW_COPY_AND_ASSIGN(MockSendAlgorithm);
 };
 
+class MockLossAlgorithm : public LossDetectionInterface {
+ public:
+  MockLossAlgorithm();
+  virtual ~MockLossAlgorithm();
+
+  MOCK_METHOD4(DetectLostPackets,
+               SequenceNumberSet(const QuicUnackedPacketMap& unacked_packets,
+                                 const QuicTime& time,
+                                 QuicPacketSequenceNumber largest_observed,
+                                 QuicTime::Delta srtt));
+  MOCK_CONST_METHOD0(GetLossTimeout, QuicTime());
+};
+
 class TestEntropyCalculator :
       public QuicReceivedEntropyHashCalculatorInterface {
  public: