NQE: Use cached estimates

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 471 matching lines @@
       const base::TimeTicks& start_time,
       int percentile) const;
   int32_t GetDownlinkThroughputKbpsEstimateInternal(
       const base::TimeTicks& start_time,
       int percentile) const;
 
   // Returns the current network ID checking by calling the platform APIs.
   // Virtualized for testing.
   virtual nqe::internal::NetworkID GetCurrentNetworkID() const;
 
+  // Notifies RTT observers of |observation|. May also trigger recomputation
+  // of effective connection type.
   void NotifyObserversOfRTT(const RttObservation& observation);
 
+  // Notifies throughput observers of |observation|. May also trigger
+  // recomputation of effective connection type.
   void NotifyObserversOfThroughput(const ThroughputObservation& observation);
 
   // Returns true only if the |request| can be used for RTT estimation.
   bool RequestProvidesRTTObservation(const URLRequest& request) const;
 
   // Recomputes effective connection type, if it was computed more than the
   // specified duration ago, or if there has been a connection change recently.
   void MaybeComputeEffectiveConnectionType();
 
   // Notifies observers of a change in effective connection type.
@@ skipping 68 matching lines @@
   void RecordCorrelationMetric(const URLRequest& request, int net_error) const;
 
   // Returns true if transport RTT should be used for computing the effective
   // connection type.
   bool UseTransportRTT() const;
 
   // Forces computation of effective connection type, and notifies observers
   // if there is a change in its value.
   void ComputeEffectiveConnectionType();
 
+  // May update the network quality of the current network if |network_id|
+  // matches the ID of the current network. |cached_network_quality| is the
+  // cached network quality of the network with id |network_id|.
+  void MaybeUpdateNetworkQualityFromCache(
+      const nqe::internal::NetworkID& network_id,
+      const nqe::internal::CachedNetworkQuality cached_network_quality);
+
   // Determines if the requests to local host can be used in estimating the
   // network quality. Set to true only for tests.
   bool use_localhost_requests_;
 
   // Determines if the responses smaller than |kMinTransferSizeInBytes|
   // or shorter than |kMinTransferSizeInBytes| can be used in estimating the
   // network quality. Set to true only for tests.
   bool use_small_responses_;
 
   // If true, default values provided by the platform are used for estimation.
@@ skipping 134 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_