relnote: Deprecate --quic_auto_tune_receive_window.

net/quic/quic_flow_controller.cc

 // 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.
 
 #include "net/quic/quic_flow_controller.h"
 
 #include "base/strings/stringprintf.h"
 #include "net/quic/quic_bug_tracker.h"
 #include "net/quic/quic_connection.h"
 #include "net/quic/quic_flags.h"
@@ skipping 91 matching lines @@
 
 void QuicFlowController::MaybeIncreaseMaxWindowSize() {
   // Core of receive window auto tuning.  This method should be called before a
   // WINDOW_UPDATE frame is sent.  Ideally, window updates should occur close to
   // once per RTT.  If a window update happens much faster than RTT, it implies
   // that the flow control window is imposing a bottleneck.  To prevent this,
   // this method will increase the receive window size (subject to a reasonable
   // upper bound).  For simplicity this algorithm is deliberately asymmetric, in
   // that it may increase window size but never decreases.
 
-  if (!FLAGS_quic_auto_tune_receive_window) {
-    return;
-  }
-
   // Keep track of timing between successive window updates.
   QuicTime now = connection_->clock()->ApproximateNow();
   QuicTime prev = prev_window_update_time_;
   prev_window_update_time_ = now;
   if (!prev.IsInitialized()) {
     DVLOG(1) << ENDPOINT << "first window update for stream " << id_;
     return;
   }
 
   if (!auto_tune_receive_window_) {
@@ skipping 123 matching lines @@
   if (receive_window_size_ != receive_window_offset_) {
     QUIC_BUG << "receive_window_size_:" << receive_window_size_
              << " != receive_window_offset:" << receive_window_offset_;
     return;
   }
   receive_window_size_ = size;
   receive_window_offset_ = size;
 }
 
 }  // namespace net