NQE: Notify observer as soon as it is added

chrome/browser/net/nqe/ui_network_quality_estimator_service.h

 // Copyright 2016 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 CHROME_BROWSER_NET_NQE_UI_NETWORK_QUALITY_ESTIMATOR_SERVICE_H_
 #define CHROME_BROWSER_NET_NQE_UI_NETWORK_QUALITY_ESTIMATOR_SERVICE_H_
 
 #include <map>
 #include <memory>
 
@@ skipping 19 matching lines @@
     : public KeyedService,
       public net::NetworkQualityEstimator::NetworkQualityProvider {
  public:
   explicit UINetworkQualityEstimatorService(Profile* profile);
   ~UINetworkQualityEstimatorService() override;
 
   // NetworkQualityProvider implementation:
   // Must be called on the UI thread.
   net::EffectiveConnectionType GetEffectiveConnectionType() const override;
   // Must be called on the UI thread. |observer| will be notified on the UI
-  // thread.
+  // thread.  |observer| would be notified of the current effective connection
+  // type in the next message pump, if it is still registered as an observer.
   void AddEffectiveConnectionTypeObserver(
       net::NetworkQualityEstimator::EffectiveConnectionTypeObserver* observer)
       override;
   // Must be called on the UI thread.
   void RemoveEffectiveConnectionTypeObserver(
       net::NetworkQualityEstimator::EffectiveConnectionTypeObserver* observer)
       override;
 
   // Registers the profile-specific network quality estimator prefs.
   static void RegisterProfilePrefs(PrefRegistrySimple* registry);
 
   // Clear the network quality estimator prefs.
   void ClearPrefs();
 
   // Tests can manually set EffectiveConnectionType, but browser tests should
   // expect that the EffectiveConnectionType could change.
   void SetEffectiveConnectionTypeForTesting(net::EffectiveConnectionType type);
 
   // Reads the prefs from the disk, parses them into a map of NetworkIDs and
   // CachedNetworkQualities, and returns the map.
   std::map<net::nqe::internal::NetworkID,
            net::nqe::internal::CachedNetworkQuality>
   ForceReadPrefsForTesting() const;
 
  private:
   class IONetworkQualityObserver;
 
+  // Notifies |observer| of the current effective connection type if |observer|
+  // is still registered as an observer.
+  void NotifyEffectiveConnectionTypeObserverIfPresent(
+      net::NetworkQualityEstimator::EffectiveConnectionTypeObserver* observer)
+      const;
+
   // KeyedService implementation:
   void Shutdown() override;
 
   // Called when the EffectiveConnectionType has updated to |type|.
   // NetworkQualityEstimator::EffectiveConnectionType is an estimate of the
   // quality of the network that may differ from the actual network type
   // reported by NetworkchangeNotifier::GetConnectionType.
   void EffectiveConnectionTypeChanged(net::EffectiveConnectionType type);
 
   // The current EffectiveConnectionType.
@@ skipping 11 matching lines @@
   // Prefs manager that is owned by this service. Created on the UI thread, but
   // used and deleted on the IO thread.
   std::unique_ptr<net::NetworkQualitiesPrefsManager> prefs_manager_;
 
   base::WeakPtrFactory<UINetworkQualityEstimatorService> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UINetworkQualityEstimatorService);
 };
 
 #endif  // CHROME_BROWSER_NET_NQE_UI_NETWORK_QUALITY_ESTIMATOR_SERVICE_H_