Use stub impl when libcros fails to load

chrome/browser/chromeos/cros/cryptohome_library.h

 // Copyright (c) 2011 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 CHROME_BROWSER_CHROMEOS_CROS_CRYPTOHOME_LIBRARY_H_
 #define CHROME_BROWSER_CHROMEOS_CROS_CRYPTOHOME_LIBRARY_H_
 #pragma once
 
 #include <string>
 
@@ skipping 10 matching lines @@
   class Delegate {
    public:
     // This will be called back on the UI thread.  Consult |return_code| for
     // further information beyond mere success or failure.
     virtual void OnComplete(bool success, int return_code) = 0;
   };
 
   CryptohomeLibrary();
   virtual ~CryptohomeLibrary();
 
+  virtual void Init() = 0;
+
   // Asks cryptohomed to try to find the cryptohome for |user_email| and then
   // use |passhash| to unlock the key.
   virtual bool CheckKey(const std::string& user_email,
                         const std::string& passhash) = 0;
 
   // Asks cryptohomed to asynchronously try to find the cryptohome for
   // |user_email| and then use |passhash| to unlock the key.
   // Returns true if the attempt is successfully initiated.
   // d->OnComplete() will be called with status info on completion.
   virtual bool AsyncCheckKey(const std::string& user_email,
@@ skipping 120 matching lines @@
   virtual bool Pkcs11IsTpmTokenReady() = 0;
 
   // Factory function, creates a new instance and returns ownership.
   // For normal usage, access the singleton via CrosLibrary::Get().
   static CryptohomeLibrary* GetImpl(bool stub);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CROS_CRYPTOHOME_LIBRARY_H_