This CL replaces user_manager::UserID with AccountId.

chrome/browser/chromeos/file_manager/external_filesystem_apitest.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 "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/path_service.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 549 matching lines @@
 // Tests for Drive file systems in multi-profile setting.
 class MultiProfileDriveFileSystemExtensionApiTest :
     public FileSystemExtensionApiTestBase {
  public:
   MultiProfileDriveFileSystemExtensionApiTest() : second_profile(NULL) {}
 
   void SetUpOnMainThread() override {
     base::FilePath user_data_directory;
     PathService::Get(chrome::DIR_USER_DATA, &user_data_directory);
     user_manager::UserManager::Get()->UserLoggedIn(
-        kSecondProfileAccount, kSecondProfileHash, false);
+        AccountId::FromUserEmail(kSecondProfileAccount), kSecondProfileHash,
+        false);
     // Set up the secondary profile.
     base::FilePath profile_dir =
         user_data_directory.Append(
             chromeos::ProfileHelper::GetUserProfileDir(
                 kSecondProfileHash).BaseName());
     second_profile =
         g_browser_process->profile_manager()->GetProfile(profile_dir);
 
     FileSystemExtensionApiTestBase::SetUpOnMainThread();
   }
@@ skipping 272 matching lines @@
                        AppFileHandlerMulti) {
   EXPECT_TRUE(
       RunFileSystemExtensionApiTest("file_browser/app_file_handler_multi",
                                     FILE_PATH_LITERAL("manifest.json"),
                                     "",
                                     FLAGS_NONE))
       << message_;
 }
 }  // namespace
 }  // namespace file_manager