RefCounted types should not have public destructors, delegate cleanup

chrome/common/net/gaia/gaia_oauth_client.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 CHROME_COMMON_NET_GAIA_GAIA_OAUTH_CLIENT_H_
 #define CHROME_COMMON_NET_GAIA_GAIA_OAUTH_CLIENT_H_
 #pragma once
 
 #include <string>
 
@@ skipping 12 matching lines @@
 
 struct OAuthClientInfo {
   std::string client_id;
   std::string client_secret;
 };
 
 class GaiaOAuthClient {
  public:
   class Delegate {
    public:
-    virtual ~Delegate() { }
-
     // Invoked on a successful response to the GetTokensFromAuthCode request.
     virtual void OnGetTokensResponse(const std::string& refresh_token,
                                      const std::string& access_token,
                                      int expires_in_seconds) = 0;
     // Invoked on a successful response to the RefreshToken request.
     virtual void OnRefreshTokenResponse(const std::string& access_token,
                                         int expires_in_seconds) = 0;
     // Invoked when there is an OAuth error with one of the requests.
     virtual void OnOAuthError() = 0;
     // Invoked when there is a network error or upon receiving an invalid
     // response. This is invoked when the maximum number of retries have been
     // exhausted. If max_retries is -1, this is never invoked.
     virtual void OnNetworkError(int response_code) = 0;
+
+   protected:
+    virtual ~Delegate() {}
   };
   GaiaOAuthClient(const std::string& gaia_url,
                   net::URLRequestContextGetter* context_getter);
   ~GaiaOAuthClient();
 
   // In the below methods, |max_retries| specifies the maximum number of times
   // we should retry on a network error in invalid response. This does not
   // apply in the case of an OAuth error (i.e. there was something wrong with
   // the input arguments). Setting |max_retries| to -1 implies infinite retries.
   void GetTokensFromAuthCode(const OAuthClientInfo& oauth_client_info,
                              const std::string& auth_code,
                              int max_retries,
                              Delegate* delegate);
   void RefreshToken(const OAuthClientInfo& oauth_client_info,
                     const std::string& refresh_token,
                     int max_retries,
                     Delegate* delegate);
 
  private:
   // The guts of the implementation live in this class.
   class Core;
   scoped_refptr<Core> core_;
   DISALLOW_COPY_AND_ASSIGN(GaiaOAuthClient);
 };
 }
 
 #endif  // CHROME_COMMON_NET_GAIA_GAIA_OAUTH_CLIENT_H_