Implement throttling behavior for LocalStorage mojo messages.

content/renderer/dom_storage/local_storage_cached_area.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_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_
 #define CONTENT_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_
 
 #include <map>
 
 #include "base/macros.h"
@@ skipping 69 matching lines @@
   // Common helper for KeyAdded() and KeyChanged()
   void KeyAddedOrChanged(const std::vector<uint8_t>& key,
                          const std::vector<uint8_t>& new_value,
                          const base::NullableString16& old_value,
                          const std::string& source);
 
   // Synchronously fetches the origin's local storage data if it hasn't been
   // fetched already.
   void EnsureLoaded();
 
+  void FlushIfNeeded();
+
   void OnSetItemComplete(const base::string16& key, bool success);
   void OnRemoveItemComplete(const base::string16& key, bool success);
   void OnClearComplete(bool success);
   void OnGetAllComplete(bool success);
 
   // Resets the object back to its newly constructed state.
   void Reset();
 
   url::Origin origin_;
   scoped_refptr<DOMStorageMap> map_;
   std::map<base::string16, int> ignore_key_mutations_;
   bool ignore_all_mutations_ = false;
   mojom::LevelDBWrapperPtr leveldb_;
   mojo::AssociatedBinding<mojom::LevelDBObserver> binding_;
   LocalStorageCachedAreas* cached_areas_;
   std::map<std::string, LocalStorageArea*> areas_;
   base::WeakPtrFactory<LocalStorageCachedArea> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(LocalStorageCachedArea);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_DOM_STORAGE_LOCAL_STORAGE_CACHED_AREA_H_