Update from https://crrev.com/306655

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 54 matching lines @@
       congestion_window_ = 10;
     }
     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);
     }
   }
 }
 
-void TcpCubicSender::ResumeConnectionState(
+bool TcpCubicSender::ResumeConnectionState(
     const CachedNetworkParameters& cached_network_params) {
   // 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;
+    return false;
   }
 
   QuicBandwidth bandwidth = QuicBandwidth::FromBytesPerSecond(
       cached_network_params.bandwidth_estimate_bytes_per_second());
   QuicTime::Delta rtt_ms =
       QuicTime::Delta::FromMilliseconds(cached_network_params.min_rtt_ms());
-  congestion_window_ = bandwidth.ToBytesPerPeriod(rtt_ms) / kMaxPacketSize;
+
+  // 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
   // start at time of estimate.
+  return true;
 }
 
 void TcpCubicSender::SetNumEmulatedConnections(int num_connections) {
   num_connections_ = max(1, num_connections);
   cubic_.SetNumConnections(num_connections_);
 }
 
 float TcpCubicSender::RenoBeta() const {
   // kNConnectionBeta is the backoff factor after loss for our N-connection
   // emulation, which emulates the effective backoff of an ensemble of N
@@ skipping 250 matching lines @@
   congestion_window_ = previous_congestion_window_;
   slowstart_threshold_ = previous_slowstart_threshold_;
   previous_congestion_window_ = 0;
 }
 
 CongestionControlType TcpCubicSender::GetCongestionControlType() const {
   return reno_ ? kReno : kCubic;
 }
 
 }  // namespace net