Enable mojo localstorage to actually store on disk.

content/browser/leveldb_wrapper_impl.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 CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_
 #define CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 72 matching lines @@
   void Delete(const std::vector<uint8_t>& key,
               const std::string& source,
               const DeleteCallback& callback) override;
   void DeleteAll(const std::string& source,
                  const DeleteAllCallback& callback) override;
   void Get(const std::vector<uint8_t>& key,
            const GetCallback& callback) override;
   void GetAll(
       mojom::LevelDBWrapperGetAllCallbackAssociatedPtrInfo complete_callback,
       const GetAllCallback& callback) override;
+  void Sync(const SyncCallback& callback) override;
 
  private:
   // Used to rate limit commits.
   class RateLimiter {
    public:
     RateLimiter(size_t desired_rate, base::TimeDelta time_quantum);
 
     void add_samples(size_t samples) { samples_ += samples;  }
 
     // Computes the total time needed to process the total samples seen
@@ skipping 50 matching lines @@
   base::WeakPtrFactory<LevelDBWrapperImpl> weak_ptr_factory_;
 
   static bool s_aggressive_flushing_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(LevelDBWrapperImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LEVELDB_WRAPPER_IMPL_H_