Allow to clear session and local storage when not backed on disk

content/browser/dom_storage/dom_storage_namespace.h

 // Copyright 2013 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_DOM_STORAGE_DOM_STORAGE_NAMESPACE_H_
 #define CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_NAMESPACE_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 34 matching lines @@
   // optional backing on disk via |session_storage_database| (may be NULL).
   DOMStorageNamespace(int64_t namespace_id,
                       const std::string& persistent_namespace_id,
                       SessionStorageDatabase* session_storage_database,
                       DOMStorageTaskRunner* task_runner);
 
   int64_t namespace_id() const { return namespace_id_; }
   const std::string& persistent_namespace_id() const {
     return persistent_namespace_id_;
   }
+  void ReadOrigins(std::vector<GURL>* origins) const;

[michaeln, 2016/05/05 00:38:23]

Can you rename to GetOriginsWithAreas()?

The more generic method name is a little misleading, "read" often means from
disk and the method sounds like it will return all origins in the namespace
including those without loaded areas. But neither of those are true.

Also please move this method down to the bottom of the public method list (and
move the method body in the .cc file down too)

[Julien Isorce Samsung, 2016/05/05 11:05:04]

Done.

 
   // Returns the storage area for the given origin,
   // creating instance if needed. Each call to open
   // must be balanced with a call to CloseStorageArea.
   DOMStorageArea* OpenStorageArea(const GURL& origin);
   void CloseStorageArea(DOMStorageArea* area);
 
   // Returns the area for |origin| if it's open, otherwise NULL.
   DOMStorageArea* GetOpenStorageArea(const GURL& origin);
 
@@ skipping 36 matching lines @@
   base::FilePath directory_;
   AreaMap areas_;
   scoped_refptr<DOMStorageTaskRunner> task_runner_;
   scoped_refptr<SessionStorageDatabase> session_storage_database_;
 };
 
 }  // namespace content
 
 
 #endif  // CONTENT_BROWSER_DOM_STORAGE_DOM_STORAGE_NAMESPACE_H_