Structure of BBR's implementation,some main classes and functions which are going to be used

webrtc/modules/remote_bitrate_estimator/test/estimators/congestion_window.h

Index: webrtc/modules/remote_bitrate_estimator/test/estimators/congestion_window.h
diff --git a/webrtc/modules/remote_bitrate_estimator/test/estimators/congestion_window.h b/webrtc/modules/remote_bitrate_estimator/test/estimators/congestion_window.h
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index 0000000000000000000000000000000000000000..5a3a460d801a63ff71e87833e539f3a15b6561d6
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+++ b/webrtc/modules/remote_bitrate_estimator/test/estimators/congestion_window.h
@@ -0,0 +1,51 @@
+/*
+ *  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 WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_TEST_ESTIMATORS_CONGESTION_WINDOW_H_
+#define WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_TEST_ESTIMATORS_CONGESTION_WINDOW_H_
+
+#include <climits>
+#include <list>
+#include <map>
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "webrtc/logging/rtc_event_log/mock/mock_rtc_event_log.h"
+#include "webrtc/modules/remote_bitrate_estimator/include/send_time_history.h"
+#include "webrtc/modules/remote_bitrate_estimator/test/bwe.h"
+
+namespace webrtc {
+namespace testing {
+namespace bwe {
+class CongestionWindow {
+ public:
+  void set_gain(float gain);
+  size_t data_inflight();
+  int64_t GetCongestionWindow();
+
+  // Packet sent from sender, meaning it is inflight
+  // until we receive it and we should add packet's size to data_inflight.
+  void PacketSent();
+
+  // Ack was received by sender, meaning
+  // packet is no longer inflight.
+  void AckReceived();
+
+  // Returnes whether or not data inflight has been under
+  // fixed value for past x rounds and y ms.
+  bool DataInflightDecreased();
+};
+}  // namespace bwe
+}  // namespace testing
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_REMOTE_BITRATE_ESTIMATOR_TEST_ESTIMATORS_CONGESTION_WINDOW_H_