Mac: implement <keygen> support, including adding generated cert to the Keychain.

net/base/cert_database.h

 // Copyright (c) 2009 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 NET_BASE_CERT_DATABASE_H_
 #define NET_BASE_CERT_DATABASE_H_
 
 #include "net/base/x509_certificate.h"
 
 namespace net {
 
 // This class provides functions to manipulate the local
 // certificate store.
 
 // TODO(gauravsh): This class could be augmented with methods
 // for all operations that manipulate the underlying system
 // certificate store.
 
 class CertDatabase {
  public:
   CertDatabase();
 
-  // Extract and Store User (Client) Certificate from a data blob.
-  // Return true if successful.
-  bool AddUserCert(const char* data, int len);
+  // Check whether this is a valid user cert that we have the private key for.
+  // Returns OK or a network error code such as ERR_CERT_CONTAINS_ERRORS.
+  int CheckUserCert(X509Certificate* cert);
+
+  // Store user (client) certificate. Assumes CheckUserCert has already passed.
+  // Returns OK or a network error code such as ERR_FAILED.
+  int AddUserCert(X509Certificate* cert);
 
  private:
   void Init();
   DISALLOW_COPY_AND_ASSIGN(CertDatabase);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_CERT_DATABASE_H_