Update from https://crrev.com/304418

net/quic/congestion_control/leaky_bucket.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/leaky_bucket.h"
-
-#include "base/time/time.h"
-
-namespace net {
-
-LeakyBucket::LeakyBucket(QuicBandwidth draining_rate)
-    : bytes_(0),
-      time_last_updated_(QuicTime::Zero()),
-      draining_rate_(draining_rate) {
-}
-
-void LeakyBucket::SetDrainingRate(QuicTime now, QuicBandwidth draining_rate) {
-  Update(now);
-  draining_rate_ = draining_rate;
-}
-
-void LeakyBucket::Add(QuicTime now, QuicByteCount bytes) {
-  Update(now);
-  bytes_ += bytes;
-}
-
-QuicTime::Delta LeakyBucket::TimeRemaining(QuicTime now) const {
-  QuicTime::Delta time_since_last_update = now.Subtract(time_last_updated_);
-  QuicTime::Delta send_delay = QuicTime::Delta::FromMicroseconds(
-      (bytes_ * base::Time::kMicrosecondsPerSecond) /
-      draining_rate_.ToBytesPerSecond());
-  if (send_delay < time_since_last_update) {
-    return QuicTime::Delta::Zero();
-  }
-  return send_delay.Subtract(time_since_last_update);
-}
-
-QuicByteCount LeakyBucket::BytesPending(QuicTime now) {
-  Update(now);
-  return bytes_;
-}
-
-void LeakyBucket::Update(QuicTime now) {
-  QuicTime::Delta elapsed_time = now.Subtract(time_last_updated_);
-  QuicByteCount bytes_cleared = draining_rate_.ToBytesPerPeriod(elapsed_time);
-  if (bytes_cleared >= bytes_) {
-    bytes_ = 0;
-  } else {
-    bytes_ -= bytes_cleared;
-  }
-  time_last_updated_ = now;
-}
-
-}  // namespace net