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diff --git a/third_party/libwebrtc/rtc_base/numerics/moving_percentile_filter.h b/third_party/libwebrtc/rtc_base/numerics/moving_percentile_filter.h
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+++ b/third_party/libwebrtc/rtc_base/numerics/moving_percentile_filter.h
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+/*
+ *  Copyright (c) 2017 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 RTC_BASE_NUMERICS_MOVING_PERCENTILE_FILTER_H_
+#define RTC_BASE_NUMERICS_MOVING_PERCENTILE_FILTER_H_
+
+#include <stddef.h>
+
+#include <cstddef>
+#include <list>
+
+#include "rtc_base/checks.h"
+#include "rtc_base/numerics/percentile_filter.h"
+
+namespace webrtc {
+
+// Class to efficiently get moving percentile filter from a stream of samples.
+template <typename T>
+class MovingPercentileFilter {
+ public:
+  // Construct filter. `percentile` defines what percentile to track and
+  // `window_size` is how many latest samples are stored for finding the
+  // percentile. `percentile` must be between 0.0 and 1.0 (inclusive) and
+  // `window_size` must be greater than 0.
+  MovingPercentileFilter(float percentile, size_t window_size);
+
+  MovingPercentileFilter(const MovingPercentileFilter&) = delete;
+  MovingPercentileFilter& operator=(const MovingPercentileFilter&) = delete;
+
+  // Insert a new sample.
+  void Insert(const T& value);
+
+  // Removes all samples;
+  void Reset();
+
+  // Get percentile over the latest window.
+  T GetFilteredValue() const;
+
+  // The number of samples that are currently stored.
+  size_t GetNumberOfSamplesStored() const;
+
+ private:
+  PercentileFilter<T> percentile_filter_;
+  std::list<T> samples_;
+  size_t samples_stored_;
+  const size_t window_size_;
+};
+
+// Convenience type for the common median case.
+template <typename T>
+class MovingMedianFilter : public MovingPercentileFilter<T> {
+ public:
+  explicit MovingMedianFilter(size_t window_size)
+      : MovingPercentileFilter<T>(0.5f, window_size) {}
+};
+
+template <typename T>
+MovingPercentileFilter<T>::MovingPercentileFilter(float percentile,
+                                                  size_t window_size)
+    : percentile_filter_(percentile),
+      samples_stored_(0),
+      window_size_(window_size) {
+  RTC_CHECK_GT(window_size, 0);
+}
+
+template <typename T>
+void MovingPercentileFilter<T>::Insert(const T& value) {
+  percentile_filter_.Insert(value);
+  samples_.emplace_back(value);
+  ++samples_stored_;
+  if (samples_stored_ > window_size_) {
+    percentile_filter_.Erase(samples_.front());
+    samples_.pop_front();
+    --samples_stored_;
+  }
+}
+
+template <typename T>
+T MovingPercentileFilter<T>::GetFilteredValue() const {
+  return percentile_filter_.GetPercentileValue();
+}
+
+template <typename T>
+void MovingPercentileFilter<T>::Reset() {
+  percentile_filter_.Reset();
+  samples_.clear();
+  samples_stored_ = 0;
+}
+
+template <typename T>
+size_t MovingPercentileFilter<T>::GetNumberOfSamplesStored() const {
+  return samples_stored_;
+}
+
+}  // namespace webrtc
+#endif  // RTC_BASE_NUMERICS_MOVING_PERCENTILE_FILTER_H_