Virtual destructors should have virtual keyword.

chrome/browser/content_settings/content_settings_policy_provider.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_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_POLICY_PROVIDER_H_
 #define CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_POLICY_PROVIDER_H_
 #pragma once
 
 // A content settings provider that takes its settings out of policies.
 
@@ skipping 68 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(PolicyDefaultProvider);
 };
 
 // PolicyProvider that provider managed content-settings.
 class PolicyProvider : public BaseProvider,
                        public NotificationObserver {
  public:
   explicit PolicyProvider(Profile* profile,
                           DefaultProviderInterface* default_provider);
-  ~PolicyProvider();
+  virtual ~PolicyProvider();
   static void RegisterUserPrefs(PrefService* prefs);
 
   // BaseProvider Implementation
   virtual void Init();
 
   virtual void SetContentSetting(
       const ContentSettingsPattern& requesting_pattern,
       const ContentSettingsPattern& embedding_pattern,
       ContentSettingsType content_type,
       const ResourceIdentifier& resource_identifier,
@@ skipping 43 matching lines @@
 
   PrefChangeRegistrar pref_change_registrar_;
   NotificationRegistrar notification_registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(PolicyProvider);
 };
 
 }  // namespace content_settings
 
 #endif  // CHROME_BROWSER_CONTENT_SETTINGS_CONTENT_SETTINGS_POLICY_PROVIDER_H_