Adding platform support check for NetworkObserver

net/android/network_change_notifier_android.h

 // Copyright (c) 2012 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_ANDROID_NETWORK_CHANGE_NOTIFIER_ANDROID_H_
 #define NET_ANDROID_NETWORK_CHANGE_NOTIFIER_ANDROID_H_
 
 #include "base/android/jni_android.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
@@ skipping 34 matching lines @@
  public:
   ~NetworkChangeNotifierAndroid() override;
 
   // NetworkChangeNotifier:
   ConnectionType GetCurrentConnectionType() const override;
   // Requires ACCESS_WIFI_STATE permission in order to provide precise WiFi link
   // speed.
   void GetCurrentMaxBandwidthAndConnectionType(
       double* max_bandwidth_mbps,
       ConnectionType* connection_type) const override;
+  bool AreNetworkHandlesCurrentlySupported() const override;
   void GetCurrentConnectedNetworks(NetworkList* network_list) const override;
   ConnectionType GetCurrentNetworkConnectionType(
       NetworkHandle network) const override;
   NetworkHandle GetCurrentDefaultNetwork() const override;
 
   // NetworkChangeNotifierDelegateAndroid::Observer:
   void OnConnectionTypeChanged() override;
   void OnMaxBandwidthChanged(double max_bandwidth_mbps,
                              ConnectionType type) override;
   void OnNetworkConnected(NetworkHandle network) override;
   void OnNetworkSoonToDisconnect(NetworkHandle network) override;
   void OnNetworkDisconnected(NetworkHandle network) override;
   void OnNetworkMadeDefault(NetworkHandle network) override;
 
   static bool Register(JNIEnv* env);
 
   // Promote GetMaxBandwidthForConnectionSubtype to public for the Android
   // delegate class.
   using NetworkChangeNotifier::GetMaxBandwidthForConnectionSubtype;
 
  private:
   friend class NetworkChangeNotifierAndroidTest;
   friend class NetworkChangeNotifierFactoryAndroid;
 
   class DnsConfigServiceThread;
 
+  // Enable NetworkHandles support for tests.
+  void ForceNetworkHandlesSupportedForTesting();
+
   NetworkChangeNotifierAndroid(NetworkChangeNotifierDelegateAndroid* delegate,
                                const DnsConfig* dns_config_for_testing);
 
   static NetworkChangeCalculatorParams NetworkChangeCalculatorParamsAndroid();
 
   NetworkChangeNotifierDelegateAndroid* const delegate_;
   scoped_ptr<DnsConfigServiceThread> dns_config_service_thread_;
+  bool force_network_handles_supported_for_testing_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkChangeNotifierAndroid);
 };
 
 }  // namespace net
 
 #endif  // NET_ANDROID_NETWORK_CHANGE_NOTIFIER_ANDROID_H_