Revert of This CL replaces e-mail with AccountId on user selection screen.

ash/test/test_session_state_delegate.cc

 // Copyright (c) 2013 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 "ash/test/test_session_state_delegate.h"
 
 #include <algorithm>
 #include <string>
 
 #include "ash/shell.h"
@@ skipping 33 matching lines @@
   base::string16 GetDisplayName() const override {
     return base::UTF8ToUTF16("Über tray Über tray Über tray Über tray");
   }
 
   base::string16 GetGivenName() const override {
     return base::UTF8ToUTF16("Über Über Über Über");
   }
 
   std::string GetEmail() const override { return display_email_; }
 
-  const AccountId& GetAccountId() const override { return account_id_; }
+  AccountId GetAccountId() const override { return account_id_; }
 
   const gfx::ImageSkia& GetImage() const override { return user_image_; }
 
   // A test user image.
   gfx::ImageSkia user_image_;
 
   std::string display_email_;
   const AccountId account_id_;
 
   DISALLOW_COPY_AND_ASSIGN(MockUserInfo);
@@ skipping 179 matching lines @@
 void TestSessionStateDelegate::AddSessionStateObserver(
     SessionStateObserver* observer) {
 }
 
 void TestSessionStateDelegate::RemoveSessionStateObserver(
     SessionStateObserver* observer) {
 }
 
 }  // namespace test
 }  // namespace ash