[login_manager] Use keygen helper to generate owner key

mock_owner_key.h

 // Copyright (c) 2010 The Chromium OS 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 LOGIN_MANAGER_MOCK_OWNER_KEY_H_
 #define LOGIN_MANAGER_MOCK_OWNER_KEY_H_
 
 #include "login_manager/owner_key.h"
 
 #include <unistd.h>
 #include <gmock/gmock.h>
 
 namespace base {
 class RSAPrivateKey;
 }
 
 namespace login_manager {
 class MockOwnerKey : public OwnerKey {
  public:
   MockOwnerKey() : OwnerKey(FilePath("")) {}
   virtual ~MockOwnerKey() {}
   MOCK_METHOD0(HaveCheckedDisk, bool());
   MOCK_METHOD0(IsPopulated, bool());
   MOCK_METHOD0(PopulateFromDiskIfPossible, bool());
   MOCK_METHOD1(PopulateFromBuffer, bool(const std::vector<uint8>&));
   MOCK_METHOD1(PopulateFromKeypair, bool(base::RSAPrivateKey*));
   MOCK_METHOD0(Persist, bool());
   MOCK_METHOD4(Verify, bool(const char*, uint32, const char*, uint32));
   MOCK_METHOD3(Sign, bool(const char*, uint32, std::vector<uint8>*));
+  MOCK_METHOD1(StartGeneration, int(ChildJobInterface*));
 };
 }  // namespace login_manager
 
 #endif  // LOGIN_MANAGER_MOCK_OWNER_KEY_H_