Add ResetModem method and call it once non_cellular activation is done.

chromeos/network/cros_network_functions.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 CHROMEOS_NETWORK_CROS_NETWORK_FUNCTIONS_H_
 #define CHROMEOS_NETWORK_CROS_NETWORK_FUNCTIONS_H_
 
 // This header is introduced to make it easy to switch from chromeos_network.cc
 // to Chrome's own DBus code.  crosbug.com/16557
 //
@@ skipping 244 matching lines @@
 
 // Configures the network service specified by |properties|.
 CHROMEOS_EXPORT void CrosConfigureService(
     const base::DictionaryValue& properties);
 
 // Changes the active cellular carrier.
 CHROMEOS_EXPORT void CrosSetCarrier(const std::string& device_path,
                                     const std::string& carrier,
                                     const NetworkOperationCallback& callback);
 
+// Resets the device.
+CHROMEOS_EXPORT void CrosReset(const std::string& device_path);
+
 }  // namespace chromeos
 
 #endif  // CHROMEOS_NETWORK_CROS_NETWORK_FUNCTIONS_H_