Use multi-profile mount point by default after browser crash and in Guest session.

chrome/browser/profiles/profile_manager_unittest.cc

 // Copyright (c) 2012 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 <string>
 
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/path_service.h"
@@ skipping 148 matching lines @@
       base::FilePath().AppendASCII(chrome::kInitialProfile);
   EXPECT_EQ(
       expected_default.value(),
       g_browser_process->profile_manager()->GetInitialProfileDir().value());
 }
 
 #if defined(OS_CHROMEOS)
 // This functionality only exists on Chrome OS.
 TEST_F(ProfileManagerTest, LoggedInProfileDir) {
   CommandLine *cl = CommandLine::ForCurrentProcess();
-  std::string profile_dir("my_user");
+  std::string profile_dir(chrome::kTestUserProfileDir);
 
   cl->AppendSwitchASCII(chromeos::switches::kLoginProfile, profile_dir);
 
   base::FilePath expected_default =
       base::FilePath().AppendASCII(chrome::kInitialProfile);
   ProfileManager* profile_manager = g_browser_process->profile_manager();
   EXPECT_EQ(expected_default.value(),
             profile_manager->GetInitialProfileDir().value());
 
   scoped_ptr<chromeos::MockUserManager> mock_user_manager;
@@ skipping 582 matching lines @@
                          dest_path2.BaseName().MaybeAsASCII());
   profile_manager->ScheduleProfileForDeletion(dest_path2,
                                               ProfileManager::CreateCallback());
   // Spin the message loop so that all the callbacks can finish running.
   base::RunLoop().RunUntilIdle();
 
   EXPECT_EQ(dest_path3, profile_manager->GetLastUsedProfile()->GetPath());
   EXPECT_EQ(profile_name3, local_state->GetString(prefs::kProfileLastUsed));
 }
 #endif  // !defined(OS_MACOSX)