Virtual destructors should have virtual keyword.

net/http/http_auth_handler_digest.h

 // Copyright (c) 2011 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 NET_HTTP_HTTP_AUTH_HANDLER_DIGEST_H_
 #define NET_HTTP_HTTP_AUTH_HANDLER_DIGEST_H_
 #pragma once
 
 #include <string>
 
@@ skipping 104 matching lines @@
     QOP_UNSPECIFIED,
     QOP_AUTH,
   };
 
   // |nonce_count| indicates how many times the server-specified nonce has
   // been used so far.
   // |nonce_generator| is used to create a client nonce, and is not owned by
   // the handler. The lifetime of the |nonce_generator| must exceed that of this
   // handler.
   HttpAuthHandlerDigest(int nonce_count, const NonceGenerator* nonce_generator);
-  ~HttpAuthHandlerDigest();
+  virtual ~HttpAuthHandlerDigest();
 
   // Parse the challenge, saving the results into this instance.
   // Returns true on success.
   bool ParseChallenge(HttpAuth::ChallengeTokenizer* challenge);
 
   // Parse an individual property. Returns true on success.
   bool ParseChallengeProperty(const std::string& name,
                               const std::string& value);
 
   // Generates a random string, to be used for client-nonce.
@@ skipping 33 matching lines @@
   DigestAlgorithm algorithm_;
   QualityOfProtection qop_;
 
   int nonce_count_;
   const NonceGenerator* nonce_generator_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_AUTH_HANDLER_DIGEST_H_