Virtual destructors should have virtual keyword.

content/browser/renderer_host/blob_message_filter.h

 // Copyright (c) 2010 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_RENDERER_HOST_BLOB_MESSAGE_FILTER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_BLOB_MESSAGE_FILTER_H_
 
 #include "base/hash_tables.h"
 #include "content/browser/browser_message_filter.h"
 
 class ChromeBlobStorageContext;
 class GURL;
 
 namespace IPC {
 class Message;
 }
 
 namespace webkit_blob {
 class BlobData;
 }
 
 class BlobMessageFilter : public BrowserMessageFilter {
  public:
   BlobMessageFilter(int process_id,
                     ChromeBlobStorageContext* blob_storage_context);
-  ~BlobMessageFilter();
+  virtual ~BlobMessageFilter();
 
   // BrowserMessageFilter implementation.
   virtual void OnChannelClosing();
   virtual bool OnMessageReceived(const IPC::Message& message,
                                  bool* message_was_ok);
 
  private:
   void OnRegisterBlobUrl(const GURL& url,
                          const scoped_refptr<webkit_blob::BlobData>& blob_data);
   void OnRegisterBlobUrlFrom(const GURL& url, const GURL& src_url);
   void OnUnregisterBlobUrl(const GURL& url);
 
   bool CheckPermission(webkit_blob::BlobData* blob_data) const;
 
   int process_id_;
   scoped_refptr<ChromeBlobStorageContext> blob_storage_context_;
 
   // Keep track of blob URLs registered in this process. Need to unregister
   // all of them when the renderer process dies.
   base::hash_set<std::string> blob_urls_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(BlobMessageFilter);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_BLOB_MESSAGE_FILTER_H_