Remove the enable_themes build flag and define.

chrome/browser/profiles/chrome_browser_main_extra_parts_profiles.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/profiles/chrome_browser_main_extra_parts_profiles.h"
 
 #include <memory>
 #include <utility>
 
 #include "build/build_config.h"
@@ skipping 271 matching lines @@
 #endif  // defined(ENABLE_MEDIA_ROUTER)
 #if !defined(OS_ANDROID)
   MediaGalleriesPreferencesFactory::GetInstance();
   NTPResourceCacheFactory::GetInstance();
 #endif
   ContentSuggestionsServiceFactory::GetInstance();
   PasswordStoreFactory::GetInstance();
   PasswordManagerSettingMigratorServiceFactory::GetInstance();
 #if !defined(OS_ANDROID)
   PinnedTabServiceFactory::GetInstance();
+  ThemeServiceFactory::GetInstance();
 #endif
 #if BUILDFLAG(ENABLE_PLUGINS)
   PluginPrefsFactory::GetInstance();
 #endif
   PrefsTabHelper::GetServiceInstance();
   policy::ProfilePolicyConnectorFactory::GetInstance();
 #if defined(OS_CHROMEOS)
   chromeos::OwnerSettingsServiceChromeOSFactory::GetInstance();
   policy::PolicyCertServiceFactory::GetInstance();
   policy::RecommendationRestorerFactory::GetInstance();
@@ skipping 25 matching lines @@
     SiteEngagementServiceFactory::GetInstance();
 
 #if BUILDFLAG(ENABLE_SPELLCHECK)
   SpellcheckServiceFactory::GetInstance();
 #endif
   suggestions::SuggestionsServiceFactory::GetInstance();
   ThumbnailServiceFactory::GetInstance();
   TabRestoreServiceFactory::GetInstance();
   TemplateURLFetcherFactory::GetInstance();
   TemplateURLServiceFactory::GetInstance();
-#if defined(ENABLE_THEMES)
-  ThemeServiceFactory::GetInstance();
-#endif
 #if defined(OS_WIN)
   TriggeredProfileResetterFactory::GetInstance();
 #endif
 #if !defined(OS_ANDROID)
   UsbChooserContextFactory::GetInstance();
 #endif
   WebDataServiceFactory::GetInstance();
 }
 
 void ChromeBrowserMainExtraPartsProfiles::PreProfileInit() {
   EnsureBrowserContextKeyedServiceFactoriesBuilt();
 }