Refactor Reading List Model to use URL as key.

components/reading_list/ios/reading_list_model_storage.h

 // Copyright 2016 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_READING_LIST_IOS_READING_LIST_MODEL_STORAGE_H_
 #define COMPONENTS_READING_LIST_IOS_READING_LIST_MODEL_STORAGE_H_
 
 #include <vector>
 
 #include "components/reading_list/ios/reading_list_entry.h"
@@ skipping 23 matching lines @@
   // transaction is commited.
   // Multiple transaction can be started at the same time. Commit will happen
   // when the last transaction is commited.
   // Returns a scoped batch update object that should be retained while the
   // batch update is performed. Deallocating this object will inform model that
   // the batch update has completed.
   virtual std::unique_ptr<ScopedBatchUpdate> EnsureBatchCreated() = 0;
 
   // Saves or updates an entry. If the entry is not yet in the database, it is
   // created.
-  virtual void SaveEntry(const ReadingListEntry& entry, bool read) = 0;
+  virtual void SaveEntry(const ReadingListEntry& entry) = 0;
 
   // Removed an entry from the storage.
   virtual void RemoveEntry(const ReadingListEntry& entry) = 0;
 
   class ScopedBatchUpdate {
    public:
     virtual ~ScopedBatchUpdate() {}
   };
 };
 
 #endif  // COMPONENTS_READING_LIST_IOS_READING_LIST_MODEL_STORAGE_H_