[Sync] Migrate bridge implementations to change list based MergeSyncData

components/sync/model/entity_change.h

 // Copyright 2015 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 COMPONENTS_SYNC_MODEL_ENTITY_CHANGE_H_
 #define COMPONENTS_SYNC_MODEL_ENTITY_CHANGE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 10 matching lines @@
   static EntityChange CreateUpdate(const std::string& storage_key,
                                    EntityDataPtr data);
   static EntityChange CreateDelete(const std::string& storage_key);
 
   EntityChange(const EntityChange& other);
   virtual ~EntityChange();
 
   std::string storage_key() const { return storage_key_; }
   ChangeType type() const { return type_; }
   const EntityData& data() const { return data_.value(); }
-  // TODO(pavely): data_ptr() is added temporarily to support converting
-  // ModelTypeSyncBridge::MergeSyncData from map to change list. Should be
-  // removed as part of crbug.com/719570.
-  const EntityDataPtr& data_ptr() const { return data_; }
 
  private:
   EntityChange(const std::string& storage_key,
                ChangeType type,
                EntityDataPtr data);
 
   std::string storage_key_;
   ChangeType type_;
   EntityDataPtr data_;
 };
 
 using EntityChangeList = std::vector<EntityChange>;
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_MODEL_ENTITY_CHANGE_H_