This CL replaces e-mail with AccountId in wallpaper manager code.

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_test_utils.cc

 // Copyright 2014 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/users/wallpaper/wallpaper_manager_test_utils.h"
 
 #include "ash/ash_switches.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
@@ skipping 19 matching lines @@
       WallpaperManager* wallpaper_manager)
       : empty_(false), wallpaper_manager_(wallpaper_manager) {
     DCHECK(wallpaper_manager_);
     wallpaper_manager_->AddObserver(this);
   }
 
   ~TestWallpaperObserverPendingListEmpty() override {
     wallpaper_manager_->RemoveObserver(this);
   }
 
-  void OnWallpaperAnimationFinished(const std::string& user_id) override {}
+  void OnWallpaperAnimationFinished(const AccountId& account_id) override {}
 
   void OnPendingListEmptyForTesting() override {
     empty_ = true;
     base::MessageLoop::current()->QuitWhenIdle();
   }
 
   void WaitForPendingListEmpty() {
     if (wallpaper_manager_->GetPendingListSizeForTesting() == 0) {
       empty_ = true;
       return;
@@ skipping 171 matching lines @@
                             kWallpaperSize,
                             kLargeChildWallpaperColor));
 
   command_line->reset(new base::CommandLine(options));
   WallpaperManager::Get()->SetCommandLineForTesting(command_line->get());
 }
 
 }  // namespace wallpaper_manager_test_utils
 
 }  // namespace chromeos