This CL replaces user_manager::UserID with AccountId.

chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager_unittest.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 <cstdlib>
 #include <cstring>
 
 #include "ash/desktop_background/desktop_background_controller.h"
 #include "ash/desktop_background/desktop_background_controller_observer.h"
 #include "ash/shell.h"
@@ skipping 54 matching lines @@
     return gfx::ImageSkia::CreateFrom1xBitmap(bitmap);
   }
 
  private:
   FakeChromeUserManager* fake_user_manager_;
   ScopedUserManagerEnabler scoped_user_manager_;
 };
 
 TEST_F(WallpaperManagerCacheTest, VerifyWallpaperCache) {
   // Add three users to known users.
-  std::string test_user_1 = "test1@example.com";
-  std::string test_user_2 = "test2@example.com";
-  std::string test_user_3 = "test3@example.com";
+  const AccountId test_account_id_1 =
+      AccountId::FromUserEmail("test1@example.com");
+  const AccountId test_account_id_2 =
+      AccountId::FromUserEmail("test2@example.com");
+  const AccountId test_account_id_3 =
+      AccountId::FromUserEmail("test3@example.com");
   base::FilePath path1("path1");
   base::FilePath path2("path2");
   base::FilePath path3("path3");
-  fake_user_manager()->AddUser(test_user_1);
-  fake_user_manager()->AddUser(test_user_2);
-  fake_user_manager()->AddUser(test_user_3);
+  fake_user_manager()->AddUser(test_account_id_1);
+  fake_user_manager()->AddUser(test_account_id_2);
+  fake_user_manager()->AddUser(test_account_id_3);
 
   // Login two users.
-  fake_user_manager()->LoginUser(test_user_1);
-  fake_user_manager()->LoginUser(test_user_2);
+  fake_user_manager()->LoginUser(test_account_id_1);
+  fake_user_manager()->LoginUser(test_account_id_2);
 
   scoped_ptr<WallpaperManager::TestApi> test_api;
   test_api.reset(new WallpaperManager::TestApi(WallpaperManager::Get()));
 
   gfx::ImageSkia test_user_1_wallpaper = CreateTestImage(SK_ColorRED);
   gfx::ImageSkia test_user_2_wallpaper = CreateTestImage(SK_ColorGREEN);
   gfx::ImageSkia test_user_3_wallpaper = CreateTestImage(SK_ColorWHITE);
-  test_api->SetWallpaperCache(test_user_1, path1, test_user_1_wallpaper);
-  test_api->SetWallpaperCache(test_user_2, path2, test_user_2_wallpaper);
-  test_api->SetWallpaperCache(test_user_3, path3, test_user_3_wallpaper);
+  test_api->SetWallpaperCache(test_account_id_1.GetUserEmail(), path1,
+                              test_user_1_wallpaper);
+  test_api->SetWallpaperCache(test_account_id_2.GetUserEmail(), path2,
+                              test_user_2_wallpaper);
+  test_api->SetWallpaperCache(test_account_id_3.GetUserEmail(), path3,
+                              test_user_3_wallpaper);
 
   test_api->ClearDisposableWallpaperCache();
 
   gfx::ImageSkia cached_wallpaper;
-  EXPECT_TRUE(test_api->GetWallpaperFromCache(test_user_1, &cached_wallpaper));
+  EXPECT_TRUE(test_api->GetWallpaperFromCache(test_account_id_1.GetUserEmail(),
+                                              &cached_wallpaper));
   base::FilePath path;
-  EXPECT_TRUE(test_api->GetPathFromCache(test_user_1, &path));
+  EXPECT_TRUE(
+      test_api->GetPathFromCache(test_account_id_1.GetUserEmail(), &path));
   // Logged in users' wallpaper cache should be kept.
   EXPECT_TRUE(cached_wallpaper.BackedBySameObjectAs(test_user_1_wallpaper));
   EXPECT_EQ(path, path1);
-  EXPECT_TRUE(test_api->GetWallpaperFromCache(test_user_2, &cached_wallpaper));
-  EXPECT_TRUE(test_api->GetPathFromCache(test_user_2, &path));
+  EXPECT_TRUE(test_api->GetWallpaperFromCache(test_account_id_2.GetUserEmail(),
+                                              &cached_wallpaper));
+  EXPECT_TRUE(
+      test_api->GetPathFromCache(test_account_id_2.GetUserEmail(), &path));
   EXPECT_TRUE(cached_wallpaper.BackedBySameObjectAs(test_user_2_wallpaper));
   EXPECT_EQ(path, path2);
 
   // Not logged in user's wallpaper cache should be cleared.
-  EXPECT_FALSE(test_api->GetWallpaperFromCache(test_user_3, &cached_wallpaper));
-  EXPECT_FALSE(test_api->GetPathFromCache(test_user_3, &path));
+  EXPECT_FALSE(test_api->GetWallpaperFromCache(test_account_id_3.GetUserEmail(),
+                                               &cached_wallpaper));
+  EXPECT_FALSE(
+      test_api->GetPathFromCache(test_account_id_3.GetUserEmail(), &path));
 }
 
 }  // namespace chromeos