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

chrome/browser/chromeos/login/user_manager_impl.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 "chrome/browser/chromeos/login/user_manager_impl.h"
 
 #include <cstddef>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 1623 matching lines @@
                              &locally_managed_users_allowed);
   return ManagedUserService::AreManagedUsersEnabled() &&
         (locally_managed_users_allowed ||
          !g_browser_process->browser_policy_connector()->IsEnterpriseManaged());
 }
 
 base::FilePath UserManagerImpl::GetUserProfileDir(
     const std::string& email) const {
   // TODO(dpolukhin): Remove Chrome OS specific profile path logic from
   // ProfileManager and use only this function to construct profile path.
+  // TODO(nkostylev): Cleanup profile dir related code paths crbug.com/294233
   base::FilePath profile_dir;
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(::switches::kMultiProfiles)) {
     const User* user = FindUser(email);
     if (user && !user->username_hash().empty()) {
       profile_dir = base::FilePath(
           chrome::kProfileDirPrefix + user->username_hash());
     }
   } else if (command_line.HasSwitch(chromeos::switches::kLoginProfile)) {
-    profile_dir = command_line.GetSwitchValuePath(
-        chromeos::switches::kLoginProfile);
+    std::string login_profile_value =
+        command_line.GetSwitchValueASCII(chromeos::switches::kLoginProfile);
+    if (login_profile_value == chrome::kLegacyProfileDir ||
+        login_profile_value == chrome::kTestUserProfileDir) {
+      profile_dir = base::FilePath(login_profile_value);
+    } else {
+      profile_dir = base::FilePath(
+          chrome::kProfileDirPrefix + login_profile_value);
+    }
   } else {
     // We should never be logged in with no profile dir unless
     // multi-profiles are enabled.
     NOTREACHED();
     profile_dir = base::FilePath();
   }
 
   ProfileManager* profile_manager = g_browser_process->profile_manager();
   profile_dir = profile_manager->user_data_dir().Append(profile_dir);
 
@@ skipping 153 matching lines @@
         base::TimeTicks::Now() - manager_creation_time_;
     if (!last_email.empty() && email != last_email &&
         time_to_login.InSeconds() <= kLogoutToLoginDelayMaxSec) {
       UMA_HISTOGRAM_CUSTOM_COUNTS("UserManager.LogoutToLoginDelay",
           time_to_login.InSeconds(), 0, kLogoutToLoginDelayMaxSec, 50);
     }
   }
 }
 
 }  // namespace chromeos