As a part of switch back to GData WAPI, update DB version.

chrome/browser/chromeos/drive/resource_metadata_storage.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 CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_
 #define CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 11 matching lines @@
 
 class ResourceEntry;
 class ResourceMetadataHeader;
 
 // Storage for ResourceMetadata which is responsible to manage entry info
 // and child-parent relationships between entries.
 class ResourceMetadataStorage {
  public:
   // This should be incremented when incompatibility change is made to DB
   // format.
-  static const int kDBVersion = 5;
+  static const int kDBVersion = 6;
 
   class Iterator {
    public:
     explicit Iterator(scoped_ptr<leveldb::Iterator> it);
     ~Iterator();
 
     // Returns true if this iterator cannot advance any more.
     bool IsAtEnd() const;
 
     // Returns the entry currently pointed by this object.
@@ skipping 65 matching lines @@
 
   // Entries stored in this storage.
   scoped_ptr<leveldb::DB> resource_map_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceMetadataStorage);
 };
 
 }  // namespace drive
 
 #endif  // CHROME_BROWSER_CHROMEOS_DRIVE_RESOURCE_METADATA_STORAGE_H_