[cros] Fake a stub user login when no --login-manager and --login-user are given.

chrome/browser/chromeos/login/user_manager_unittest.cc

Index: chrome/browser/chromeos/login/user_manager_unittest.cc
diff --git a/chrome/browser/chromeos/login/user_manager_unittest.cc b/chrome/browser/chromeos/login/user_manager_unittest.cc
index 63e98bb84ec0ccc68eedaae1553d76a1ce3b06c6..a0e9ef0c7a990e9138c89dd9a86a328e9e3ce7cb 100644
--- a/chrome/browser/chromeos/login/user_manager_unittest.cc
+++ b/chrome/browser/chromeos/login/user_manager_unittest.cc
@@ -62,7 +62,6 @@ class UserManagerTest : public testing::Test {
     UserManager::RegisterPrefs(local_state_.get());
 
     old_user_manager_ = UserManager::Get();
-    // A stub user is automatically logged in by UserManager. Reset this.
     ResetUserManager();
   }
 
@@ -101,11 +100,6 @@ class UserManagerTest : public testing::Test {
 
   void ResetUserManager() {
     user_manager_impl.reset(new UserManagerImpl());
-    // Clean up the stub user that gets created in the UserManagerImpl
-    // constructor.
-    delete user_manager_impl->logged_in_user_;
-    user_manager_impl->logged_in_user_ = NULL;
-    user_manager_impl->is_current_user_ephemeral_ = false;
     UserManager::Set(user_manager_impl.get());
   }