Add DatagramClientSocket::BindToDefaultNetwork(),GetBoundNetwork()

net/base/network_change_notifier.h

Index: net/base/network_change_notifier.h
diff --git a/net/base/network_change_notifier.h b/net/base/network_change_notifier.h
index 4290331cddf259652a26253a3aa797a2fa69f011..217eda3fa66e5bf70df5adef7938b371d9a5faa5 100644
--- a/net/base/network_change_notifier.h
+++ b/net/base/network_change_notifier.h
@@ -303,14 +303,14 @@ class NET_EXPORT NetworkChangeNotifier {
   // CONNECTION_UNKNOWN when unimplemented.
   static ConnectionType GetNetworkConnectionType(NetworkHandle network);
 
-  // Returns the device's current default network connection. This is the
+  // Determines the device's current default network connection. This is the
   // network used for newly created socket communication for sockets that are
   // not explicitly bound to a particular network (e.g. via
-  // DatagramClientSocket.BindToNetwork). Returns |kInvalidNetworkHandle| if
-  // there is no default connected network.
-  // Only implemented for Android (Lollipop and newer), returns
-  // |kInvalidNetworkHandle| when unimplemented.
-  static NetworkHandle GetDefaultNetwork();
+  // DatagramClientSocket.BindToNetwork). Sets |*network| to the default network
+  // or |kInvalidNetworkHandle| if there is no default connected network.
+  // Only implemented for Android (Lollipop and newer).
+  // Returns a net error code.
+  static int GetDefaultNetwork(NetworkHandle* network);
 
   // Retrieve the last read DnsConfig. This could be expensive if the system has
   // a large HOSTS file.
@@ -484,7 +484,7 @@ class NET_EXPORT NetworkChangeNotifier {
   virtual void GetCurrentConnectedNetworks(NetworkList* network_list) const;
   virtual ConnectionType GetCurrentNetworkConnectionType(
       NetworkHandle network) const;
-  virtual NetworkHandle GetCurrentDefaultNetwork() const;
+  virtual int GetCurrentDefaultNetwork(NetworkHandle* network) const;
 
   // Broadcasts a notification to all registered observers.  Note that this
   // happens asynchronously, even for observers on the current thread, even in