Add interval estimator to remote bitrate estimator

webrtc/modules/congestion_controller/probing_interval_estimator.h

Index: webrtc/modules/congestion_controller/probing_interval_estimator.h
diff --git a/webrtc/modules/congestion_controller/probing_interval_estimator.h b/webrtc/modules/congestion_controller/probing_interval_estimator.h
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+/*
+ *  Copyright (c) 2016 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 WEBRTC_MODULES_CONGESTION_CONTROLLER_PROBING_INTERVAL_ESTIMATOR_H_
+#define WEBRTC_MODULES_CONGESTION_CONTROLLER_PROBING_INTERVAL_ESTIMATOR_H_
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/optional.h"
+#include "webrtc/modules/remote_bitrate_estimator/aimd_rate_control.h"
+
+namespace webrtc {
+
+class ProbingIntervalEstimator {
+ public:
+  explicit ProbingIntervalEstimator(const AimdRateControl* aimd_rate_control);
+
+  ProbingIntervalEstimator(int min_interval_ms,
+                           int max_interval_ms,
+                           const AimdRateControl* aimd_rate_control);
+  rtc::Optional<int> GetIntervalMs() const;
+
+ private:
+  const int min_interval_ms_;
+  const int max_interval_ms_;
+  const AimdRateControl* const aimd_rate_control_;
+  RTC_DISALLOW_COPY_AND_ASSIGN(ProbingIntervalEstimator);
+};
+
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_CONGESTION_CONTROLLER_PROBING_INTERVAL_ESTIMATOR_H_