Don't generate a certificate browse button or passphrase field if cert path contains SETTINGS:

chrome/browser/chromeos/login/network_screen.cc

 // Copyright (c) 2010 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.
 
 #include "chrome/browser/chromeos/login/network_screen.h"
 
 #include "app/l10n_util.h"
 #include "base/utf_string_conversions.h"
 #include "base/logging.h"
 #include "chrome/browser/chromeos/cros/cros_library.h"
@@ skipping 203 matching lines @@
   if (network &&
       !networks_.IsNetworkConnected(type, id)) {
     if (NetworkList::NETWORK_WIFI == network->network_type) {
       if (network->wifi_network.encrypted()) {
         OpenPasswordDialog(network->wifi_network);
         return;
       } else {
         WaitForConnection(network);
         chromeos::CrosLibrary::Get()->GetNetworkLibrary()->
             ConnectToWifiNetwork(network->wifi_network,
-                                 string16(), string16(), string16());
+                                 std::string(), std::string(), std::string());
       }
     } else if (NetworkList::NETWORK_CELLULAR == network->network_type) {
       WaitForConnection(network);
       chromeos::CrosLibrary::Get()->GetNetworkLibrary()->
           ConnectToCellularNetwork(network->cellular_network);
     }
   }
 }
 
 void NetworkScreen::EnableWiFi() {
@@ skipping 84 matching lines @@
   if (connection_timer_.IsRunning())
     connection_timer_.Stop();
   connection_timer_.Start(base::TimeDelta::FromSeconds(kConnectionTimeoutSec),
                           this,
                           &NetworkScreen::OnConnectionTimeout);
   if (continue_pressed_)
     ShowConnectingStatus();
 }
 
 }  // namespace chromeos