[Sync] Refactored ProfileSyncService and remove its backend() function

chrome/browser/sync/glue/autofill_profile_model_associator.h

 // Copyright (c) 2010 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.
 
 #ifndef CHROME_BROWSER_SYNC_GLUE_AUTOFILL_PROFILE_MODEL_ASSOCIATOR_H_
 #define CHROME_BROWSER_SYNC_GLUE_AUTOFILL_PROFILE_MODEL_ASSOCIATOR_H_
 #pragma once
 
 #include <map>
 #include <set>
@@ skipping 75 matching lines @@
 
   // Remove the association that corresponds to the given sync id.
   virtual void Disassociate(int64 sync_id);
 
   // TODO(lipalani) Bug 64111. Returns whether a node with the
   // given permanent tag was found and update
   // |sync_id| with that node's id. No current use. To Implement
   // only for completeness.
   virtual bool GetSyncIdForTaggedNode(const std::string& tag, int64* sync_id);
 
-  // Returns sync service instance.
-  ProfileSyncService* sync_service() { return sync_service_; }
-
   static bool OverwriteProfileWithServerData(
       AutoFillProfile* merge_into,
       const sync_pb::AutofillProfileSpecifics& specifics);
 
  protected:
   AutofillProfileModelAssociator();
   bool TraverseAndAssociateChromeAutoFillProfiles(
       sync_api::WriteTransaction* write_trans,
       const sync_api::ReadNode& autofill_root,
       const std::vector<AutoFillProfile*>& all_profiles_from_db,
@@ skipping 79 matching lines @@
   std::vector<std::string> profiles_to_delete;
   std::vector<AutoFillProfile*> updated_profiles;
   std::vector<AutoFillProfile*> new_profiles;  // We own these pointers.
   ~DataBundle() { STLDeleteElements(&new_profiles); }
 };
 
 }  // namespace browser_sync
 
 #endif  // CHROME_BROWSER_SYNC_GLUE_AUTOFILL_PROFILE_MODEL_ASSOCIATOR_H_