NQE: Add Transport RTT based GetECT algorithm

net/nqe/network_quality_estimator.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NET_NQE_NETWORK_QUALITY_ESTIMATOR_H_
 #define NET_NQE_NETWORK_QUALITY_ESTIMATOR_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 354 matching lines @@
   // This does not use a unordered_map or hash_map for code simplicity (key just
   // implements operator<, rather than hash and equality) and because the map is
   // tiny.
   typedef std::map<NetworkID, nqe::internal::CachedNetworkQuality>
       CachedNetworkQualities;
 
   // Algorithms supported by network quality estimator for computing effective
   // connection type.
   enum class EffectiveConnectionTypeAlgorithm {
     HTTP_RTT_AND_DOWNSTREAM_THROUGHOUT = 0,
+    TRANSPORT_RTT_OR_DOWNSTREAM_THROUGHOUT,
     EFFECTIVE_CONNECTION_TYPE_ALGORITHM_LAST
   };
 
   // Map from algorithm names to EffectiveConnectionTypeAlgorithm.
   const std::map<std::string, EffectiveConnectionTypeAlgorithm>
       algorithm_name_to_enum_;
 
   // The default algorithm to be used if the algorithm value is not available
   // through field trial parameters.
   static const EffectiveConnectionTypeAlgorithm
@@ skipping 93 matching lines @@
   void RecordAccuracyAfterMainFrame(base::TimeDelta measuring_duration) const;
 
   // Returns the effective type of the current connection based on only the
   // samples observed after |start_time|. Uses HTTP RTT and downstream
   // throughput to compute the effective connection type, and requires both of
   // them to have a valid value.
   EffectiveConnectionType
   GetRecentEffectiveConnectionTypeHttpRTTAndDownstreamThroughput(
       const base::TimeTicks& start_time) const;
 
+  // Returns the effective type of the current connection based on only the
+  // samples observed after |start_time|. Uses transport RTT and downstream
+  // throughput to compute the effective connection type, and requires at least
+  // one of them to have a valid value.
+  EffectiveConnectionType
+  GetRecentEffectiveConnectionTypeTransportRTTOrDownstreamThroughput(
+      const base::TimeTicks& start_time) const;
+
   // Values of external estimate provider status. This enum must remain
   // synchronized with the enum of the same name in
   // metrics/histograms/histograms.xml.
   enum NQEExternalEstimateProviderStatus {
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_NOT_AVAILABLE,
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_AVAILABLE,
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_QUERIED,
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_QUERY_SUCCESSFUL,
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_CALLBACK,
     EXTERNAL_ESTIMATE_PROVIDER_STATUS_RTT_AVAILABLE,
@@ skipping 111 matching lines @@
   base::ThreadChecker thread_checker_;
 
   base::WeakPtrFactory<NetworkQualityEstimator> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkQualityEstimator);
 };
 
 }  // namespace net
 
 #endif  // NET_NQE_NETWORK_QUALITY_ESTIMATOR_H_