Make quota logic obey durable storage permission

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 27 matching lines @@
 
    protected:
     virtual ~Observer();
   };
 
   SpecialStoragePolicy();
 
   // Protected storage is not subject to removal by the browsing data remover.
   virtual bool IsStorageProtected(const GURL& origin) = 0;
 
-  // Unlimited storage is not subject to 'quotas'.
+  // Unlimited storage is not subject to quota or storage pressure eviction.
   virtual bool IsStorageUnlimited(const GURL& origin) = 0;
 
+  // Durable storage is not subject to storage pressure eviction.
+  virtual bool IsStorageDurable(const GURL& origin) = 0;
+
   // Some origins (e.g. installed apps) have access to the size of the remaining
   // disk capacity.
   virtual bool CanQueryDiskSize(const GURL& origin) = 0;
 
   // 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;
@@ skipping 12 matching lines @@
   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_