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diff --git a/third_party/libwebrtc/api/units/data_rate.h b/third_party/libwebrtc/api/units/data_rate.h
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+++ b/third_party/libwebrtc/api/units/data_rate.h
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+/*
+ *  Copyright (c) 2018 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef API_UNITS_DATA_RATE_H_
+#define API_UNITS_DATA_RATE_H_
+
+#ifdef WEBRTC_UNIT_TEST
+#include <ostream>  // no-presubmit-check TODO(webrtc:8982)
+#endif              // WEBRTC_UNIT_TEST
+
+#include <limits>
+#include <string>
+#include <type_traits>
+
+#include "api/units/data_size.h"
+#include "api/units/frequency.h"
+#include "api/units/time_delta.h"
+#include "rtc_base/checks.h"
+#include "rtc_base/units/unit_base.h"  // IWYU pragma: export
+
+namespace webrtc {
+// DataRate is a class that represents a given data rate. This can be used to
+// represent bandwidth, encoding bitrate, etc. The internal storage is bits per
+// second (bps).
+class DataRate final : public rtc_units_impl::RelativeUnit<DataRate> {
+ public:
+  template <typename T>
+  static constexpr DataRate BitsPerSec(T value) {
+    static_assert(std::is_arithmetic<T>::value, "");
+    return FromValue(value);
+  }
+  template <typename T>
+  static constexpr DataRate BytesPerSec(T value) {
+    static_assert(std::is_arithmetic<T>::value, "");
+    return FromFraction(8, value);
+  }
+  template <typename T>
+  static constexpr DataRate KilobitsPerSec(T value) {
+    static_assert(std::is_arithmetic<T>::value, "");
+    return FromFraction(1000, value);
+  }
+  static constexpr DataRate Infinity() { return PlusInfinity(); }
+
+  DataRate() = delete;
+
+  template <typename T = int64_t>
+  constexpr T bps() const {
+    return ToValue<T>();
+  }
+  template <typename T = int64_t>
+  constexpr T bytes_per_sec() const {
+    return ToFraction<8, T>();
+  }
+  template <typename T = int64_t>
+  constexpr T kbps() const {
+    return ToFraction<1000, T>();
+  }
+  constexpr int64_t bps_or(int64_t fallback_value) const {
+    return ToValueOr(fallback_value);
+  }
+  constexpr int64_t kbps_or(int64_t fallback_value) const {
+    return ToFractionOr<1000>(fallback_value);
+  }
+
+ private:
+  // Bits per second used internally to simplify debugging by making the value
+  // more recognizable.
+  friend class rtc_units_impl::UnitBase<DataRate>;
+  using RelativeUnit::RelativeUnit;
+  static constexpr bool one_sided = true;
+};
+
+namespace data_rate_impl {
+inline constexpr int64_t Microbits(const DataSize& size) {
+  constexpr int64_t kMaxBeforeConversion =
+      std::numeric_limits<int64_t>::max() / 8000000;
+  RTC_DCHECK_LE(size.bytes(), kMaxBeforeConversion)
+      << "size is too large to be expressed in microbits";
+  return size.bytes() * 8000000;
+}
+
+inline constexpr int64_t MillibytePerSec(const DataRate& size) {
+  constexpr int64_t kMaxBeforeConversion =
+      std::numeric_limits<int64_t>::max() / (1000 / 8);
+  RTC_DCHECK_LE(size.bps(), kMaxBeforeConversion)
+      << "rate is too large to be expressed in microbytes per second";
+  return size.bps() * (1000 / 8);
+}
+}  // namespace data_rate_impl
+
+inline constexpr DataRate operator/(const DataSize size,
+                                    const TimeDelta duration) {
+  return DataRate::BitsPerSec(data_rate_impl::Microbits(size) / duration.us());
+}
+inline constexpr TimeDelta operator/(const DataSize size, const DataRate rate) {
+  return TimeDelta::Micros(data_rate_impl::Microbits(size) / rate.bps());
+}
+inline constexpr DataSize operator*(const DataRate rate,
+                                    const TimeDelta duration) {
+  int64_t microbits = rate.bps() * duration.us();
+  return DataSize::Bytes((microbits + 4000000) / 8000000);
+}
+inline constexpr DataSize operator*(const TimeDelta duration,
+                                    const DataRate rate) {
+  return rate * duration;
+}
+
+inline constexpr DataSize operator/(const DataRate rate,
+                                    const Frequency frequency) {
+  int64_t millihertz = frequency.millihertz<int64_t>();
+  // Note that the value is truncated here reather than rounded, potentially
+  // introducing an error of .5 bytes if rounding were expected.
+  return DataSize::Bytes(data_rate_impl::MillibytePerSec(rate) / millihertz);
+}
+inline constexpr Frequency operator/(const DataRate rate, const DataSize size) {
+  return Frequency::MilliHertz(data_rate_impl::MillibytePerSec(rate) /
+                               size.bytes());
+}
+inline constexpr DataRate operator*(const DataSize size,
+                                    const Frequency frequency) {
+  RTC_DCHECK(frequency.IsZero() ||
+             size.bytes() <= std::numeric_limits<int64_t>::max() / 8 /
+                                 frequency.millihertz<int64_t>());
+  int64_t millibits_per_second =
+      size.bytes() * 8 * frequency.millihertz<int64_t>();
+  return DataRate::BitsPerSec((millibits_per_second + 500) / 1000);
+}
+inline constexpr DataRate operator*(const Frequency frequency,
+                                    const DataSize size) {
+  return size * frequency;
+}
+
+std::string ToString(DataRate value);
+inline std::string ToLogString(DataRate value) {
+  return ToString(value);
+}
+
+#ifdef WEBRTC_UNIT_TEST
+inline std::ostream& operator<<(  // no-presubmit-check TODO(webrtc:8982)
+    std::ostream& stream,         // no-presubmit-check TODO(webrtc:8982)
+    DataRate value) {
+  return stream << ToString(value);
+}
+#endif  // WEBRTC_UNIT_TEST
+
+}  // namespace webrtc
+
+#endif  // API_UNITS_DATA_RATE_H_