[Sync] Get SyncServce instead of ProfileSyncService.

chrome/browser/sync/profile_sync_service_factory.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 "chrome/browser/sync/profile_sync_service_factory.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/singleton.h"
@@ skipping 85 matching lines @@
 }  // anonymous namespace
 
 // static
 ProfileSyncServiceFactory* ProfileSyncServiceFactory::GetInstance() {
   return base::Singleton<ProfileSyncServiceFactory>::get();
 }
 
 // static
 ProfileSyncService* ProfileSyncServiceFactory::GetForProfile(
     Profile* profile) {
-  if (!ProfileSyncService::IsSyncAllowedByFlag())
-    return nullptr;
-
   return static_cast<ProfileSyncService*>(
-      GetInstance()->GetServiceForBrowserContext(profile, true));
+      GetSyncServiceForBrowserContext(profile));
 }
 
 // static
 syncer::SyncService* ProfileSyncServiceFactory::GetSyncServiceForBrowserContext(
     content::BrowserContext* context) {
-  return GetForProfile(Profile::FromBrowserContext(context));
+  if (!ProfileSyncService::IsSyncAllowedByFlag()) {
+    return nullptr;
+  }
+
+  return static_cast<syncer::SyncService*>(
+      GetInstance()->GetServiceForBrowserContext(context, true));
 }
 
 ProfileSyncServiceFactory::ProfileSyncServiceFactory()
     : BrowserContextKeyedServiceFactory(
         "ProfileSyncService",
         BrowserContextDependencyManager::GetInstance()) {
   // The ProfileSyncService depends on various SyncableServices being around
   // when it is shut down.  Specify those dependencies here to build the proper
   // destruction order.
   DependsOn(AboutSigninInternalsFactory::GetInstance());
@@ skipping 131 matching lines @@
 
 // static
 void ProfileSyncServiceFactory::SetSyncClientFactoryForTest(
     SyncClientFactory* client_factory) {
   client_factory_ = client_factory;
 }
 
 // static
 ProfileSyncServiceFactory::SyncClientFactory*
     ProfileSyncServiceFactory::client_factory_ = nullptr;