GetProfileFromAccountId() should not return a null point if a valid account id is provided.

chrome/browser/ui/ash/multi_user/multi_user_util.cc

 // Copyright 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/ui/ash/multi_user/multi_user_util.h"
 
 #include <vector>
 
 #include "base/strings/string_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "components/signin/core/account_id/account_id.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 #if defined(OS_CHROMEOS)
+#include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_window_manager.h"
 #include "components/user_manager/user_manager.h"
 #endif
 
 namespace multi_user_util {
 
 AccountId GetAccountIdFromProfile(Profile* profile) {
   return GetAccountIdFromEmail(
       profile->GetOriginalProfile()->GetProfileUserName());
 }
 
 AccountId GetAccountIdFromEmail(const std::string& email) {
   // |email| and profile name could be empty if not yet logged in or guest mode.
   return email.empty() ? EmptyAccountId()
                        : AccountId::FromUserEmail(gaia::CanonicalizeEmail(
                              gaia::SanitizeEmail(email)));
 }
 
 Profile* GetProfileFromAccountId(const AccountId& account_id) {
   // Unit tests can end up here without a |g_browser_process|.
   if (!g_browser_process || !g_browser_process->profile_manager())
-    return NULL;
+    return nullptr;
 
   std::vector<Profile*> profiles =
       g_browser_process->profile_manager()->GetLoadedProfiles();
 
   std::vector<Profile*>::const_iterator profile_iterator = profiles.begin();
   for (; profile_iterator != profiles.end(); ++profile_iterator) {
     if (GetAccountIdFromProfile(*profile_iterator) == account_id)
       return *profile_iterator;
   }
-  return NULL;
+
+#if defined(OS_CHROMEOS)
+  // If in a session the refresh token is revoked, GetAccountIdFromProfile()
+  // returns an empty account id which will cause the profile not being fetched
+  // properly. In this case we fall back to use GetProfileByUser() function.

[Mr4D (OOO till 08-26), 2016/02/17 04:05:07]

Please add also a comment that in case the refresh token is revoked, we will
force log out the user within 120 seconds.
You might also want to reference the issue number which made this change
necessary.

+  const user_manager::User* user =
+      user_manager::UserManager::Get()->FindUser(account_id);
+  if (user)
+    return chromeos::ProfileHelper::Get()->GetProfileByUser(user);
+#endif
+
+  return nullptr;
 }
 
 Profile* GetProfileFromWindow(aura::Window* window) {
 #if defined(OS_CHROMEOS)
   chrome::MultiUserWindowManager* manager =
       chrome::MultiUserWindowManager::GetInstance();
   // We might come here before the manager got created - or in a unit test.
   if (!manager)
     return nullptr;
   const AccountId account_id = manager->GetUserPresentingWindow(window);
@@ skipping 30 matching lines @@
 #if defined(OS_CHROMEOS)
   if (!chrome::MultiUserWindowManager::GetInstance()->IsWindowOnDesktopOfUser(
           window, GetCurrentAccountId())) {
     chrome::MultiUserWindowManager::GetInstance()->ShowWindowForUser(
         window, GetCurrentAccountId());
   }
 #endif
 }
 
 }  // namespace multi_user_util