Allow WindowedFilter to use arbitrary time type instead of QuicTime. No functional change.

net/quic/congestion_control/rtt_stats.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // A convenience class to store rtt samples and calculate smoothed rtt.
 
 #ifndef NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_
 #define NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_
 
 #include <stdint.h>
@@ skipping 81 matching lines @@
   QuicTime::Delta mean_deviation_;
   int64_t initial_rtt_us_;
 
   // Variables used to force a new windowed_min_rtt measurement within
   // num_samples_for_forced_min_.
   QuicTime::Delta forced_windowed_min_rtt_;
   QuicTime forced_windowed_min_rtt_time_;
   uint32_t num_samples_for_forced_min_;
 
   // Windowed min_rtt.
-  WindowedFilter<QuicTime::Delta, MinFilter<QuicTime::Delta>> windowed_min_rtt_;
+  WindowedFilter<QuicTime::Delta,
+                 MinFilter<QuicTime::Delta>,
+                 QuicTime,
+                 QuicTime::Delta>
+      windowed_min_rtt_;
 
   DISALLOW_COPY_AND_ASSIGN(RttStats);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_