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diff --git a/chromium/media/capture/content/smooth_event_sampler.h b/chromium/media/capture/content/smooth_event_sampler.h
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+++ b/chromium/media/capture/content/smooth_event_sampler.h
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+// Copyright (c) 2015 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.
+
+#ifndef MEDIA_CAPTURE_SMOOTH_EVENT_SAMPLER_H_
+#define MEDIA_CAPTURE_SMOOTH_EVENT_SAMPLER_H_
+
+#include "base/time/time.h"
+#include "media/base/media_export.h"
+
+namespace media {
+
+// Filters a sequence of events to achieve a target frequency.
+class MEDIA_EXPORT SmoothEventSampler {
+ public:
+  SmoothEventSampler(base::TimeDelta min_capture_period,
+                     int redundant_capture_goal);
+
+  // Get/Set minimum capture period. When setting a new value, the state of the
+  // sampler is retained so that sampling will continue smoothly.
+  base::TimeDelta min_capture_period() const { return min_capture_period_; }
+  void SetMinCapturePeriod(base::TimeDelta p);
+
+  // Add a new event to the event history, and consider whether it ought to be
+  // sampled. The event is not recorded as a sample until RecordSample() is
+  // called.
+  void ConsiderPresentationEvent(base::TimeTicks event_time);
+
+  // Returns true if the last event considered should be sampled.
+  bool ShouldSample() const;
+
+  // Operates on the last event added by ConsiderPresentationEvent(), marking
+  // it as sampled. After this point we are current in the stream of events, as
+  // we have sampled the most recent event.
+  void RecordSample();
+
+  // Returns true if, at time |event_time|, sampling should occur because too
+  // much time will have passed relative to the last event and/or sample.
+  bool IsOverdueForSamplingAt(base::TimeTicks event_time) const;
+
+  // Returns true if ConsiderPresentationEvent() has been called since the last
+  // call to RecordSample().
+  bool HasUnrecordedEvent() const;
+
+ private:
+  base::TimeDelta min_capture_period_;
+  const int redundant_capture_goal_;
+  base::TimeDelta token_bucket_capacity_;
+
+  base::TimeTicks current_event_;
+  base::TimeTicks last_sample_;
+  int overdue_sample_count_;
+  base::TimeDelta token_bucket_;
+
+  DISALLOW_COPY_AND_ASSIGN(SmoothEventSampler);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_CAPTURE_SMOOTH_EVENT_SAMPLER_H_