Add a QUIC connection option(BWMX) to resume to the max bandwidth

net/quic/congestion_control/tcp_cubic_sender.cc

 // Copyright (c) 2012 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.
 
 #include "net/quic/congestion_control/tcp_cubic_sender.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram.h"
 #include "net/quic/congestion_control/prr_sender.h"
@@ skipping 60 matching lines @@
     }
     if (using_pacing) {
       // Disable the ack train mode in hystart when pacing is enabled, since it
       // may be falsely triggered.
       hybrid_slow_start_.set_ack_train_detection(false);
     }
   }
 }
 
 bool TcpCubicSender::ResumeConnectionState(
-    const CachedNetworkParameters& cached_network_params) {
+    const CachedNetworkParameters& cached_network_params,
+    bool max_bandwidth_resumption) {
   // If the previous bandwidth estimate is less than an hour old, store in
   // preparation for doing bandwidth resumption.
   int64 seconds_since_estimate =
       clock_->WallNow().ToUNIXSeconds() - cached_network_params.timestamp();
   if (seconds_since_estimate > kNumSecondsPerHour) {
     return false;
   }
 
   QuicBandwidth bandwidth = QuicBandwidth::FromBytesPerSecond(
-      cached_network_params.bandwidth_estimate_bytes_per_second());
+      max_bandwidth_resumption
+          ? cached_network_params.max_bandwidth_estimate_bytes_per_second()
+          : cached_network_params.bandwidth_estimate_bytes_per_second());
   QuicTime::Delta rtt_ms =
       QuicTime::Delta::FromMilliseconds(cached_network_params.min_rtt_ms());
 
   // Make sure CWND is in appropriate range (in case of bad data).
   QuicPacketCount new_congestion_window =
       bandwidth.ToBytesPerPeriod(rtt_ms) / kMaxPacketSize;
   congestion_window_ = max(min(new_congestion_window, kMaxTcpCongestionWindow),
                            kMinCongestionWindowForBandwidthResumption);
 
   // TODO(rjshade): Set appropriate CWND when previous connection was in slow
@@ skipping 255 matching lines @@
   hybrid_slow_start_.Restart();
   slowstart_threshold_ = congestion_window_ / 2;
   congestion_window_ = min_congestion_window_;
 }
 
 CongestionControlType TcpCubicSender::GetCongestionControlType() const {
   return reno_ ? kReno : kCubic;
 }
 
 }  // namespace net