Add EffectiveConnectionType enum to the system profile proto

components/metrics/net/network_metrics_provider.h

Index: components/metrics/net/network_metrics_provider.h
diff --git a/components/metrics/net/network_metrics_provider.h b/components/metrics/net/network_metrics_provider.h
index da47689d2746187f5e7ba4e874a07c867327139b..c147b2d834212f9c7c2e2b9fb264e36eef6e0e14 100644
--- a/components/metrics/net/network_metrics_provider.h
+++ b/components/metrics/net/network_metrics_provider.h
@@ -10,11 +10,17 @@
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/histogram_base.h"
+#include "base/threading/thread_checker.h"
 #include "components/metrics/metrics_provider.h"
 #include "components/metrics/net/wifi_access_point_info_provider.h"
 #include "components/metrics/proto/system_profile.pb.h"
 #include "net/base/network_change_notifier.h"
 #include "net/base/network_interfaces.h"
+#include "net/nqe/effective_connection_type.h"
+
+namespace net {
+class NetworkQualityEstimator;
+}
 
 namespace metrics {
 
@@ -27,9 +33,20 @@ class NetworkMetricsProvider
   // Creates a NetworkMetricsProvider, where |io_task_runner| is used to post
   // network info collection tasks.
   explicit NetworkMetricsProvider(base::TaskRunner* io_task_runner);
+
+  // Sets the network quality estimator which lives on |task_runner|.

[RyanSturm, 2016/12/28 21:53:11]

nit: s/lives on/can be accessed via/
or "which lives on the thread that task_runner is associated with"?

[tbansal1, 2017/01/03 17:25:13]

Done.

+  void ProvideNetworkQualityEstimator(
+      net::NetworkQualityEstimator* network_quality_estimator,
+      const scoped_refptr<base::SequencedTaskRunner>& task_runner);
+
   ~NetworkMetricsProvider() override;
 
  private:
+  FRIEND_TEST_ALL_PREFIXES(NetworkMetricsProviderTest, EffectiveConnectionType);
+
+  // Listens to the changes in the effective conection type.
+  class EffectiveConnectionTypeObserver;
+
   // MetricsProvider:
   void ProvideGeneralMetrics(ChromeUserMetricsExtension* uma_proto) override;
   void ProvideSystemProfileMetrics(SystemProfileProto* system_profile) override;
@@ -41,6 +58,8 @@ class NetworkMetricsProvider
   SystemProfileProto::Network::ConnectionType GetConnectionType() const;
   SystemProfileProto::Network::WifiPHYLayerProtocol GetWifiPHYLayerProtocol()
       const;
+  SystemProfileProto::Network::EffectiveConnectionType
+  GetEffectiveConnectionType() const;
 
   // Posts a call to net::GetWifiPHYLayerProtocol on the blocking pool.
   void ProbeWifiPHYLayerProtocol();
@@ -57,6 +76,10 @@ class NetworkMetricsProvider
   // Logs metrics that are functions of other metrics being uploaded.
   void LogAggregatedMetrics();
 
+  // Notifies |this| that the effective connection type of the current network
+  // has changed to |type|.
+  void OnEffectiveConnectionTypeChanged(net::EffectiveConnectionType type);
+
   // Task runner used for blocking file I/O.
   base::TaskRunner* io_task_runner_;
 
@@ -79,6 +102,24 @@ class NetworkMetricsProvider
   base::HistogramBase::Count total_aborts_;
   base::HistogramBase::Count total_codes_;
 
+  // Listens to the changes in the effective connection type. Initialized and
+  // destroyed on |network_quality_task_runner_|.

[RyanSturm, 2016/12/28 21:53:11]

same nit here. I'm not sure that taskrunner should be talked about as if it were
just a thread. 

[tbansal1, 2017/01/03 17:25:13]

Done.

+  std::unique_ptr<EffectiveConnectionTypeObserver>
+      effective_connection_type_observer_;
+
+  // Task runner on which |effective_connection_type_observer_| is initialized

[RyanSturm, 2016/12/28 21:53:11]

same nit: s/Task runner/Corresponds to the thread/

[tbansal1, 2017/01/03 17:25:13]

Done.

+  // and destroyed.
+  scoped_refptr<base::SequencedTaskRunner> network_quality_task_runner_;
+
+  // Last known effective connection type.
+  net::EffectiveConnectionType effective_connection_type_;
+
+  // True if |effective_connection_type_| changed during the lifetime of the
+  // log.
+  bool effective_connection_type_is_ambiguous_;
+
+  base::ThreadChecker thread_checker_;
+
   base::WeakPtrFactory<NetworkMetricsProvider> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkMetricsProvider);