We should use UserID object to identify users instead of username.

chrome/browser/chromeos/extensions/wallpaper_private_api.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/extensions/wallpaper_private_api.h"
 
 #include <map>
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 17 matching lines @@
 #include "chrome/browser/chromeos/login/users/wallpaper/wallpaper_manager.h"
 #include "chrome/browser/chromeos/profiles/profile_helper.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/profile_sync_service.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
 #include "chromeos/chromeos_switches.h"
 #include "components/user_manager/user.h"
+#include "components/user_manager/user_id.h"
 #include "components/user_manager/user_manager.h"
 #include "components/wallpaper/wallpaper_layout.h"
 #include "content/public/browser/browser_thread.h"
 #include "extensions/browser/event_router.h"
 #include "grit/components_strings.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/webui/web_ui_util.h"
 #include "ui/strings/grit/app_locale_settings.h"
 #include "url/gurl.h"
 
@@ skipping 285 matching lines @@
   ProfileSyncService* sync =
       ProfileSyncServiceFactory::GetInstance()->GetForProfile(profile);
   base::DictionaryValue* dict = new base::DictionaryValue();
   SetResult(dict);
   dict->SetBoolean("syncThemes",
                    sync->GetActiveDataTypes().Has(syncer::THEMES));
   return true;
 }
 
 WallpaperPrivateSetWallpaperIfExistsFunction::
-    WallpaperPrivateSetWallpaperIfExistsFunction() {}
+    WallpaperPrivateSetWallpaperIfExistsFunction() : user_id_(std::string(), std::string()) {}

[Denis Kuznetsov (DE-MUC), 2015/06/10 16:50:45]

EmptyUserID() ?

 
 WallpaperPrivateSetWallpaperIfExistsFunction::
     ~WallpaperPrivateSetWallpaperIfExistsFunction() {}
 
 bool WallpaperPrivateSetWallpaperIfExistsFunction::RunAsync() {
   params = set_wallpaper_if_exists::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(params);
 
-  // Gets email address from caller, ensuring multiprofile compatibility.
+  // Gets User ID from caller, ensuring multiprofile compatibility.
   const user_manager::User* user = GetUserFromBrowserContext(browser_context());
-  user_id_ = user->email();
+  user_id_ = user->GetUserID();
 
   base::FilePath wallpaper_path;
   base::FilePath fallback_path;
   chromeos::WallpaperManager::WallpaperResolution resolution =
       chromeos::WallpaperManager::Get()->GetAppropriateResolution();
 
   std::string file_name = GURL(params->url).ExtractFileName();
   CHECK(PathService::Get(chrome::DIR_CHROMEOS_WALLPAPERS,
                          &wallpaper_path));
   fallback_path = wallpaper_path.Append(file_name);
@@ skipping 52 matching lines @@
     const gfx::ImageSkia& image) {
   // Set unsafe_wallpaper_decoder_ to null since the decoding already finished.
   unsafe_wallpaper_decoder_ = NULL;
 
   chromeos::WallpaperManager* wallpaper_manager =
       chromeos::WallpaperManager::Get();
   wallpaper::WallpaperLayout layout = wallpaper_api_util::GetLayoutEnum(
       wallpaper_base::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->GetUserID();
   wallpaper_manager->SetWallpaperFromImageSkia(
       user_id_, image, layout, update_wallpaper);
   bool is_persistent = !user_manager::UserManager::Get()
                             ->IsCurrentUserNonCryptohomeDataEphemeral();
   wallpaper::WallpaperInfo info = {params->url,
                                    layout,
                                    user_manager::User::ONLINE,
                                    base::Time::Now().LocalMidnight()};
   wallpaper_manager->SetUserWallpaperInfo(user_id_, info, is_persistent);
   SetResult(new base::FundamentalValue(true));
   Profile* profile = Profile::FromBrowserContext(browser_context());
   // This API is only available to the component wallpaper picker. We do not
   // need to show the app's name if it is the component wallpaper picker. So set
   // the pref to empty string.
   profile->GetPrefs()->SetString(prefs::kCurrentWallpaperAppName,
                                  std::string());
   SendResponse(true);
 }
 
 void WallpaperPrivateSetWallpaperIfExistsFunction::OnFileNotExists(
     const std::string& error) {
   SetResult(new base::FundamentalValue(false));
   OnFailure(error);
 }
 
-WallpaperPrivateSetWallpaperFunction::WallpaperPrivateSetWallpaperFunction() {
+WallpaperPrivateSetWallpaperFunction::WallpaperPrivateSetWallpaperFunction() : user_id_(std::string(), std::string()) {

[Denis Kuznetsov (DE-MUC), 2015/06/10 16:50:46]

EmptyUserID() ?

 }
 
 WallpaperPrivateSetWallpaperFunction::~WallpaperPrivateSetWallpaperFunction() {
 }
 
 bool WallpaperPrivateSetWallpaperFunction::RunAsync() {
   params = set_wallpaper::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(params);
 
-  // Gets email address from caller, ensuring multiprofile compatibility.
+  // Gets user ID address from caller, ensuring multiprofile compatibility.
   const user_manager::User* user = GetUserFromBrowserContext(browser_context());
-  user_id_ = user->email();
+  user_id_ = user->GetUserID();
 
   StartDecode(params->wallpaper);
 
   return true;
 }
 
 void WallpaperPrivateSetWallpaperFunction::OnWallpaperDecoded(
     const gfx::ImageSkia& image) {
   wallpaper_ = image;
   // Set unsafe_wallpaper_decoder_ to null since the decoding already finished.
@@ skipping 51 matching lines @@
 
 void WallpaperPrivateSetWallpaperFunction::SetDecodedWallpaper(
     scoped_ptr<gfx::ImageSkia> image) {
   chromeos::WallpaperManager* wallpaper_manager =
       chromeos::WallpaperManager::Get();
 
   wallpaper::WallpaperLayout layout = wallpaper_api_util::GetLayoutEnum(
       wallpaper_base::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->GetUserID();
   wallpaper_manager->SetWallpaperFromImageSkia(
       user_id_, *image.get(), layout, update_wallpaper);
 
   bool is_persistent = !user_manager::UserManager::Get()
                             ->IsCurrentUserNonCryptohomeDataEphemeral();
   wallpaper::WallpaperInfo info = {params->url,
                                    layout,
                                    user_manager::User::ONLINE,
                                    base::Time::Now().LocalMidnight()};
   Profile* profile = Profile::FromBrowserContext(browser_context());
@@ skipping 10 matching lines @@
     WallpaperPrivateResetWallpaperFunction() {}
 
 WallpaperPrivateResetWallpaperFunction::
     ~WallpaperPrivateResetWallpaperFunction() {}
 
 bool WallpaperPrivateResetWallpaperFunction::RunAsync() {
   chromeos::WallpaperManager* wallpaper_manager =
       chromeos::WallpaperManager::Get();
   user_manager::UserManager* user_manager = user_manager::UserManager::Get();
 
-  std::string user_id = user_manager->GetActiveUser()->email();
+  user_manager::UserID user_id = user_manager->GetActiveUser()->GetUserID();
   wallpaper_manager->RemoveUserWallpaperInfo(user_id);
 
   wallpaper::WallpaperInfo info = {std::string(),
                                    wallpaper::WALLPAPER_LAYOUT_CENTER,
                                    user_manager::User::DEFAULT,
                                    base::Time::Now().LocalMidnight()};
   bool is_persistent =
       !user_manager->IsCurrentUserNonCryptohomeDataEphemeral();
   wallpaper_manager->SetUserWallpaperInfo(user_id, info, is_persistent);
 
   wallpaper_manager->SetDefaultWallpaperNow(user_id);
   Profile* profile = Profile::FromBrowserContext(browser_context());
   // This API is only available to the component wallpaper picker. We do not
   // need to show the app's name if it is the component wallpaper picker. So set
   // the pref to empty string.
   profile->GetPrefs()->SetString(prefs::kCurrentWallpaperAppName,
                                  std::string());
   return true;
 }
 
 WallpaperPrivateSetCustomWallpaperFunction::
-    WallpaperPrivateSetCustomWallpaperFunction() {}
+    WallpaperPrivateSetCustomWallpaperFunction() : user_id_(std::string(), std::string()) {}

[Denis Kuznetsov (DE-MUC), 2015/06/10 16:50:45]

EmptyUserID() ?

 
 WallpaperPrivateSetCustomWallpaperFunction::
     ~WallpaperPrivateSetCustomWallpaperFunction() {}
 
 bool WallpaperPrivateSetCustomWallpaperFunction::RunAsync() {
   params = set_custom_wallpaper::Params::Create(*args_);
   EXTENSION_FUNCTION_VALIDATE(params);
 
-  // Gets email address from caller, ensuring multiprofile compatibility.
+  // Gets User ID from caller, ensuring multiprofile compatibility.
   const user_manager::User* user = GetUserFromBrowserContext(browser_context());
-  user_id_ = user->email();
+  user_id_ = user->GetUserID();
   user_id_hash_ = user->username_hash();
 
   StartDecode(params->wallpaper);
 
   return true;
 }
 
 void WallpaperPrivateSetCustomWallpaperFunction::OnWallpaperDecoded(
     const gfx::ImageSkia& image) {
   chromeos::WallpaperManager* wallpaper_manager =
       chromeos::WallpaperManager::Get();
   base::FilePath thumbnail_path = wallpaper_manager->GetCustomWallpaperPath(
       wallpaper::kThumbnailWallpaperSubDir, user_id_hash_, params->file_name);
 
   sequence_token_ = BrowserThread::GetBlockingPool()->GetNamedSequenceToken(
       wallpaper::kWallpaperSequenceTokenName);
   scoped_refptr<base::SequencedTaskRunner> task_runner =
       BrowserThread::GetBlockingPool()->
           GetSequencedTaskRunnerWithShutdownBehavior(sequence_token_,
               base::SequencedWorkerPool::BLOCK_SHUTDOWN);
 
   wallpaper::WallpaperLayout layout = wallpaper_api_util::GetLayoutEnum(
       wallpaper_base::ToString(params->layout));
 
   bool update_wallpaper =
-      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->email();
+      user_id_ == user_manager::UserManager::Get()->GetActiveUser()->GetUserID();
   wallpaper_manager->SetCustomWallpaper(user_id_,
                                         user_id_hash_,
                                         params->file_name,
                                         layout,
                                         user_manager::User::CUSTOMIZED,
                                         image,
                                         update_wallpaper);
   unsafe_wallpaper_decoder_ = NULL;
 
   Profile* profile = Profile::FromBrowserContext(browser_context());
@@ skipping 60 matching lines @@
   wallpaper::WallpaperInfo info;
   wallpaper_manager->GetLoggedInUserWallpaperInfo(&info);
   if (info.type != user_manager::User::CUSTOMIZED) {
     SetError("Only custom wallpaper can change layout.");
     SendResponse(false);
     return false;
   }
   info.layout = wallpaper_api_util::GetLayoutEnum(
       wallpaper_base::ToString(params->layout));
 
-  std::string email =
-      user_manager::UserManager::Get()->GetActiveUser()->email();
+  const user_manager::UserID user_id =
+      user_manager::UserManager::Get()->GetActiveUser()->GetUserID();
   bool is_persistent = !user_manager::UserManager::Get()
                             ->IsCurrentUserNonCryptohomeDataEphemeral();
-  wallpaper_manager->SetUserWallpaperInfo(email, info, is_persistent);
+  wallpaper_manager->SetUserWallpaperInfo(user_id, info, is_persistent);
   wallpaper_manager->UpdateWallpaper(false /* clear_cache */);
   SendResponse(true);
 
   // Gets email address while at UI thread.
   return true;
 }
 
 WallpaperPrivateMinimizeInactiveWindowsFunction::
     WallpaperPrivateMinimizeInactiveWindowsFunction() {
 }
@@ skipping 27 matching lines @@
 
 WallpaperPrivateGetThumbnailFunction::~WallpaperPrivateGetThumbnailFunction() {
 }
 
 bool WallpaperPrivateGetThumbnailFunction::RunAsync() {
   scoped_ptr<get_thumbnail::Params> params(
       get_thumbnail::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params);
 
   base::FilePath thumbnail_path;
-  std::string email =
-      user_manager::UserManager::Get()->GetActiveUser()->email();
   if (params->source == wallpaper_private::WALLPAPER_SOURCE_ONLINE) {
     std::string file_name = GURL(params->url_or_file).ExtractFileName();
     CHECK(PathService::Get(chrome::DIR_CHROMEOS_WALLPAPER_THUMBNAILS,
                            &thumbnail_path));
     thumbnail_path = thumbnail_path.Append(file_name);
   } else {
     if (!IsOEMDefaultWallpaper()) {
       SetError("No OEM wallpaper.");
       SendResponse(false);
       return false;
@@ skipping 157 matching lines @@
                  this, file_list));
 }
 
 void WallpaperPrivateGetOfflineWallpaperListFunction::OnComplete(
     const std::vector<std::string>& file_list) {
   base::ListValue* results = new base::ListValue();
   results->AppendStrings(file_list);
   SetResult(results);
   SendResponse(true);
 }