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..f951bd4f7fa533b72dd88a7ec01243c31cf6d38f 100644
--- a/net/base/network_quality_estimator.h
+++ b/net/base/network_quality_estimator.h
@@ -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);
@@ -165,6 +168,10 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest,
                            TestLRUCacheMaximumSize);
   FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest, TestGetMedianRTTSince);
+  FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest,
+                           TestExternalEstimateProvider);
+  FRIEND_TEST_ALL_PREFIXES(NetworkQualityEstimatorTest,
+                           TestExternalEstimateProviderMergeEstimates);
 
   // NetworkQuality is used to cache the quality of a network connection.
   class NET_EXPORT_PRIVATE NetworkQuality {
@@ -352,12 +359,18 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   // Maximum number of observations that can be held in the ObservationBuffer.
   static const size_t kMaximumObservationsBufferSize = 300;
 
+  // Time duration (in milliseconds) after which the estimate provided by
+  // external estimate provider is considered stale.
+  static const int kExternalEstimateProviderFreshnessDurationMsec =
+      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;
+  // 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(
@@ -396,6 +409,22 @@ class NET_EXPORT_PRIVATE NetworkQualityEstimator
   // observations.
   bool RequestProvidesUsefulObservations(const URLRequest& request) 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_BOUNDARY
+  };
+
+  // Records the metrics related to external estimate provider.
+  void RecordExternalEstimateProviderMetrics(
+      NQEExternalEstimateProviderStatus status) const;
+
   // Determines if the requests to local host can be used in estimating the
   // network quality. Set to true only for tests.
   const bool allow_localhost_requests_;
@@ -439,7 +468,7 @@ 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_;
 
   base::ThreadChecker thread_checker_;