Added implementation of four functions in the BBR congestion controller.

webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc

+/*
+ *  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.
+ *
+ */
+
+#include "webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.h"
+
+namespace webrtc {
+namespace testing {
+namespace bwe {
+MaxBandwidthFilter::MaxBandwidthFilter() {}
+
+MaxBandwidthFilter::~MaxBandwidthFilter() {}
+
+bool MaxBandwidthFilter::FullBandwidthReached(float growth_target,
+                                              int max_rounds_without_growth) {
+  // Minimal bandwidth necessary to assume that better bandwidth can still be
+  // found and full bandwidth is not reached.
+  int64_t minimal_bandwidth = bandwidth_last_round_ * growth_target;
+  if (max_bandwidth_estimate_ >= minimal_bandwidth) {
+    bandwidth_last_round_ = max_bandwidth_estimate_;
+    rounds_without_growth_ = 0;
+    return false;
+  }
+  rounds_without_growth_++;
+  if (rounds_without_growth_ >= max_rounds_without_growth)
+    return true;
+  return false;
+}
+}  // namespace bwe
+}  // namespace testing
+}  // namespace webrtc