[chromeos] Fix chrome://cryptohome crash

chrome/browser/ui/webui/about_ui.cc

 // 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.
 
 #include "chrome/browser/ui/webui/about_ui.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 517 matching lines @@
   output.append("<h3>CryptohomeLibrary:</h3>");
   output.append("<table>");
   output.append(AddBoolRow("IsMounted", cryptohome->IsMounted()));
   output.append(AddBoolRow("TpmIsReady", cryptohome->TpmIsReady()));
   output.append(AddBoolRow("TpmIsEnabled", cryptohome->TpmIsEnabled()));
   output.append(AddBoolRow("TpmIsOwned", cryptohome->TpmIsOwned()));
   output.append(AddBoolRow("TpmIsBeingOwned", cryptohome->TpmIsBeingOwned()));
   output.append(AddBoolRow("Pkcs11IsTpmTokenReady", is_tpm_token_ready));
   output.append("</table>");
 
-  std::string token_name, user_pin;
-  crypto::GetTPMTokenInfo(&token_name, &user_pin);
   output.append("<h3>crypto:</h3>");
   output.append("<table>");
   output.append(AddBoolRow("IsTPMTokenReady", crypto::IsTPMTokenReady()));
+  std::string token_name, user_pin;
+  if (crypto::IsTPMTokenReady())
+    crypto::GetTPMTokenInfo(&token_name, &user_pin);
   output.append(AddStringRow("token_name", token_name));
   output.append(AddStringRow("user_pin", std::string(user_pin.length(), '*')));
   output.append("</table>");
   AppendFooter(&output);
 
   source->FinishDataRequest(output, request_id);
 }
 
 void FinishCryptohomeDataRequest(scoped_refptr<AboutUIHTMLSource> source,
                                  const std::string& query,
@@ skipping 848 matching lines @@
 }
 
 AboutUI::AboutUI(content::WebUI* web_ui, const std::string& name)
     : WebUIController(web_ui) {
   Profile* profile = Profile::FromWebUI(web_ui);
   ChromeURLDataManager::DataSource* source =
       new AboutUIHTMLSource(name, profile);
   if (source)
     profile->GetChromeURLDataManager()->AddDataSource(source);
 }