Populate EEP estimate in NQE

net/base/network_quality_estimator.h

Index: net/base/network_quality_estimator.h
diff --git a/net/base/network_quality_estimator.h b/net/base/network_quality_estimator.h
index aba0313b6ec924c68376ced83ecd7eeb5391c207..65cab569a43c87367dac88779470689e78dd854b 100644
--- a/net/base/network_quality_estimator.h
+++ b/net/base/network_quality_estimator.h
@@ -51,12 +51,12 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
 
   // Returns true if RTT is available and sets |rtt| to estimated RTT.
   // Virtualized for testing. |rtt| should not be null.
-  virtual bool GetRTTEstimate(base::TimeDelta* rtt) const;
+  virtual bool GetRTTEstimate(base::TimeDelta* rtt);
 
   // Returns true if downlink throughput is available and sets |kbps| to
   // estimated downlink throughput (in Kilobits per second).
   // Virtualized for testing. |kbps| should not be null.
-  virtual bool GetDownlinkThroughputKbpsEstimate(int32_t* kbps) const;
+  virtual bool GetDownlinkThroughputKbpsEstimate(int32_t* kbps);
 
   // Notifies NetworkQualityEstimator that the response header of |request| has
   // been received.
@@ -70,14 +70,14 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   // RTT observations since |begin_timestamp|.
   // Virtualized for testing. |rtt| should not be null.
   virtual bool GetRecentMedianRTT(const base::TimeTicks& begin_timestamp,
-                                  base::TimeDelta* rtt) const;
+                                  base::TimeDelta* rtt);
 
   // Returns true if median downstream throughput is available and sets |kbps|
   // to the median of downstream Kbps observations since |begin_timestamp|.
   // Virtualized for testing. |kbps| should not be null.
   virtual bool GetRecentMedianDownlinkThroughputKbps(
       const base::TimeTicks& begin_timestamp,
-      int32_t* kbps) const;
+      int32_t* kbps);
 
   // SocketPerformanceWatcherFactory implementation:
   scoped_ptr<SocketPerformanceWatcher> CreateTCPSocketPerformanceWatcher()
@@ -149,6 +149,9 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   void OnConnectionTypeChanged(
       NetworkChangeNotifier::ConnectionType type) override;
 
+  // ExternalEstimateProvider::UpdatedEstimateObserver implementation.
+  void OnUpdatedEstimateAvailable() override;
+
  private:
   FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest, StoreObservations);
   FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest, TestKbpsRTTUpdates);
@@ -352,12 +355,22 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   // Maximum number of observations that can be held in the ObservationBuffer.
   static const size_t kMaximumObservationsBufferSize = 300;
 
+  // Minimum time duration (in milliseconds) between consecutive queries to
+  // external estimate provider.
+  static const int kExternalEstimateProviderQueryIntervalMsec = 5 * 60 * 1000;
+
   // Returns the RTT value to be used when the valid RTT is unavailable. Readers
   // should discard RTT if it is set to the value returned by |InvalidRTT()|.
   static const base::TimeDelta InvalidRTT();
 
-  // ExternalEstimateProvider::UpdatedEstimateObserver implementation:
-  void OnUpdatedEstimateAvailable() override;
+  // May call |QueryExternalEstimateProvider| if the most recent call to
+  // external estimate provider was more than
+  // |kExternalEstimateProviderQueryIntervalMsec| back.
+  void MaybeQueryExternalEstimateProvider();
+
+  // Queries the external estimate provider for the latest network quality
+  // estimates, and adds those estimates to the current observation buffer.
+  void QueryExternalEstimateProvider();
 
   // Obtains operating parameters from the field trial parameters.
   void ObtainOperatingParams(
@@ -439,7 +452,22 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
 
   // ExternalEstimateProvider that provides network quality using operating
   // system APIs. May be NULL.
-  const scoped_ptr<ExternalEstimateProvider> external_estimates_provider_;
+  const scoped_ptr<ExternalEstimateProvider> external_estimate_provider_;
+
+  // Time when the external estimate provider was last queried.
+  base::TimeTicks external_estimate_request_time_;
+
+  // 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_BOUNDARY
+  };
 
   base::ThreadChecker thread_checker_;