Added implementation of three classes in BBR,with unit-tests.

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

Index: webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc
diff --git a/webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc b/webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc
index 91e99346bfec2790ef81f031f84751aa78adb9f1..f6c883bbfb1f60fd3cb5f651a927d61d95e3e4dd 100644
--- a/webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc
+++ b/webrtc/modules/remote_bitrate_estimator/test/estimators/max_bandwidth_filter.cc
@@ -14,10 +14,26 @@
 namespace webrtc {
 namespace testing {
 namespace bwe {
-MaxBandwidthFilter::MaxBandwidthFilter() {}
+MaxBandwidthFilter::MaxBandwidthFilter()
+    : bandwidth_last_round_(0),
+      round_bandwidth_updated_(0),
+      max_bandwidth_estimate_(0),
+      rounds_without_growth_(0) {}
 
 MaxBandwidthFilter::~MaxBandwidthFilter() {}
 
+// Rounds are units for packets rtt_time, after packet has been acknowledged,
+// one round has passed from its send time.
+void MaxBandwidthFilter::AddBandwidthSample(int64_t sample_bytes_per_ms,
+                                            int64_t round,
+                                            size_t filter_size_round) {
+  if (round - round_bandwidth_updated_ >= filter_size_round ||
+      sample_bytes_per_ms >= max_bandwidth_estimate_) {
+    max_bandwidth_estimate_ = sample_bytes_per_ms;
+    round_bandwidth_updated_ = round;
+  }
+}
+
 bool MaxBandwidthFilter::FullBandwidthReached(float growth_target,
                                               int max_rounds_without_growth) {
   // Minimal bandwidth necessary to assume that better bandwidth can still be
@@ -29,9 +45,7 @@ bool MaxBandwidthFilter::FullBandwidthReached(float growth_target,
     return false;
   }
   rounds_without_growth_++;
-  if (rounds_without_growth_ >= max_rounds_without_growth)
-    return true;
-  return false;
+  return rounds_without_growth_ >= max_rounds_without_growth;
 }
 }  // namespace bwe
 }  // namespace testing