Compute effective connection type dynamically

net/nqe/network_quality_estimator.cc

Index: net/nqe/network_quality_estimator.cc
diff --git a/net/nqe/network_quality_estimator.cc b/net/nqe/network_quality_estimator.cc
index 96c0f3c92ccac8217bfc93906fa22031ccd95a22..8b55d568e406e9bc4fa1f0ff9a47b52be73b7a40 100644
--- a/net/nqe/network_quality_estimator.cc
+++ b/net/nqe/network_quality_estimator.cc
@@ -363,8 +363,6 @@ NetworkQualityEstimator::NetworkQualityEstimator(
                     .find(GetEffectiveConnectionTypeAlgorithm(variation_params))
                     ->second),
       tick_clock_(new base::DefaultTickClock()),
-      effective_connection_type_recomputation_interval_(
-          base::TimeDelta::FromSeconds(15)),
       last_connection_change_(tick_clock_->NowTicks()),
       current_network_id_(nqe::internal::NetworkID(
           NetworkChangeNotifier::ConnectionType::CONNECTION_UNKNOWN,
@@ -374,6 +372,10 @@ NetworkQualityEstimator::NetworkQualityEstimator(
       effective_connection_type_at_last_main_frame_(
           EFFECTIVE_CONNECTION_TYPE_UNKNOWN),
       external_estimate_provider_(std::move(external_estimates_provider)),
+      effective_connection_type_recomputation_interval_(
+          base::TimeDelta::FromSeconds(15)),
+      number_of_rtt_samples_at_last_ect_computation_(0),
+      number_of_bandwidth_samples_at_last_ect_computation_(0),
       effective_connection_type_(EFFECTIVE_CONNECTION_TYPE_UNKNOWN),
       min_signal_strength_since_connection_change_(INT32_MAX),
       max_signal_strength_since_connection_change_(INT32_MIN),
@@ -1650,7 +1652,18 @@ void NetworkQualityEstimator::MaybeRecomputeEffectiveConnectionType() {
   // has not updated.
   if (now - last_effective_connection_type_computation_ <
           effective_connection_type_recomputation_interval_ &&
-      last_connection_change_ < last_effective_connection_type_computation_) {
+      last_connection_change_ < last_effective_connection_type_computation_ &&
+      // Recompute the effective connection type if the previously computed
+      // effective connection type was unknown.
+      effective_connection_type_ != EFFECTIVE_CONNECTION_TYPE_UNKNOWN &&
+      // Recompute the effective connection type if the number of samples
+      // available now are more than twice in count than the number of
+      // samples that were available when the effective connection type was
+      // last computed.
+      number_of_rtt_samples_at_last_ect_computation_ * 2 >=
+          rtt_observations_.Size() &&
+      number_of_bandwidth_samples_at_last_ect_computation_ * 2 >=
+          downstream_throughput_kbps_observations_.Size()) {
     return;
   }
 
@@ -1660,6 +1673,10 @@ void NetworkQualityEstimator::MaybeRecomputeEffectiveConnectionType() {
 
   if (past_type != effective_connection_type_)
     NotifyObserversOfEffectiveConnectionTypeChanged();
+
+  number_of_rtt_samples_at_last_ect_computation_ = rtt_observations_.Size();
+  number_of_bandwidth_samples_at_last_ect_computation_ =
+      downstream_throughput_kbps_observations_.Size();
 }
 
 void NetworkQualityEstimator::