Allow script to request durable storage permission (chrome side)

storage/browser/quota/special_storage_policy.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 STORAGE_BROWSER_QUOTA_SPECIAL_STORAGE_POLICY_H_
 #define STORAGE_BROWSER_QUOTA_SPECIAL_STORAGE_POLICY_H_
 
 #include <string>
 
 #include "base/memory/ref_counted.h"
@@ skipping 44 matching lines @@
   // Checks if the origin contains per-site isolated storage.
   virtual bool HasIsolatedStorage(const GURL& origin) = 0;
 
   // Some origins are only allowed to store session-only data which is deleted
   // when the session ends.
   virtual bool IsStorageSessionOnly(const GURL& origin) = 0;
 
   // Returns true if some origins are only allowed session-only storage.
   virtual bool HasSessionOnlyOrigins() = 0;
 
+  virtual bool IsStorageDurable(const GURL& origin) = 0;
+
   // Adds/removes an observer, the policy does not take
   // ownership of the observer. Should only be called on the IO thread.
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
  protected:
   friend class base::RefCountedThreadSafe<SpecialStoragePolicy>;
   virtual ~SpecialStoragePolicy();
   void NotifyGranted(const GURL& origin, int change_flags);
   void NotifyRevoked(const GURL& origin, int change_flags);
   void NotifyCleared();
 
   base::ObserverList<Observer> observers_;
 };
 
 }  // namespace storage
 
 #endif  // STORAGE_BROWSER_QUOTA_SPECIAL_STORAGE_POLICY_H_