user_manager component: Add UserManagerBase class.

chrome/browser/chromeos/login/users/mock_user_manager.cc

 // Copyright 2014 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/users/mock_user_manager.h"
 
 #include "chrome/browser/chromeos/login/users/fake_supervised_user_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 
 namespace chromeos {
@@ skipping 18 matching lines @@
 }
 
 user_manager::User* MockUserManager::GetLoggedInUser() {
   return user_list_.empty() ? NULL : user_list_.front();
 }
 
 user_manager::UserList MockUserManager::GetUnlockUsers() const {
   return user_list_;
 }
 
-const std::string& MockUserManager::GetOwnerEmail() {
+const std::string& MockUserManager::GetOwnerEmail() const {
   return GetLoggedInUser()->email();
 }
 
 const user_manager::User* MockUserManager::GetActiveUser() const {
   return GetLoggedInUser();
 }
 
 user_manager::User* MockUserManager::GetActiveUser() {
   return GetLoggedInUser();
 }
@@ skipping 46 matching lines @@
 
 void MockUserManager::ClearUserList() {
   // Can't use STLDeleteElements because of the protected destructor of User.
   user_manager::UserList::iterator user;
   for (user = user_list_.begin(); user != user_list_.end(); ++user)
     delete *user;
   user_list_.clear();
 }
 
 }  // namespace chromeos