Relax strict quota limit checks when reading pre-existing DomStorage database files. The other chec…

webkit/dom_storage/dom_storage_map.h

 // Copyright (c) 2012 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 WEBKIT_DOM_STORAGE_DOM_STORAGE_MAP_H_
 #define WEBKIT_DOM_STORAGE_DOM_STORAGE_MAP_H_
 #pragma once
 
 #include <map>
 
@@ skipping 12 matching lines @@
  public:
   DomStorageMap(size_t quota);
 
   unsigned Length() const;
   NullableString16 Key(unsigned index);
   NullableString16 GetItem(const string16& key) const;
   bool SetItem(const string16& key, const string16& value,
                NullableString16* old_value);
   bool RemoveItem(const string16& key, string16* old_value);
 
-  // Replaces values_ with |map|. Returns true on success, false
-  // if the swap was prevented because |map| would exceed this
-  // DomStorageMap's quota_.
-  bool SwapValues(ValuesMap* map);
+  // Swaps this instances values_ with |map|.
+  // Note: to grandfather in pre-existing files that are overbudget,
+  // this method does not do quota checking.
+  void SwapValues(ValuesMap* map);
+
+  // Creates a new instance of DomStorageMap containing
+  // a deep copy of values_.
   DomStorageMap* DeepCopy() const;
 
   size_t bytes_used() const { return bytes_used_; }
 
  private:
   friend class base::RefCountedThreadSafe<DomStorageMap>;
   ~DomStorageMap();
 
   void ResetKeyIterator();
 
   ValuesMap values_;
   ValuesMap::const_iterator key_iterator_;
   unsigned last_key_index_;
   size_t bytes_used_;
   size_t quota_;
 };
 
 }  // namespace dom_storage
 
 #endif  // WEBKIT_DOM_STORAGE_DOM_STORAGE_MAP_H_