Virtual destructors should have virtual keyword.

chrome/browser/mach_broker_mac.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_MACH_BROKER_H_
 #define CHROME_BROWSER_MACH_BROKER_H_
 #pragma once
 
 #include <map>
 #include <string>
@@ skipping 68 matching lines @@
   // Implement |ProcessMetrics::PortProvider|.
   virtual mach_port_t TaskForPid(base::ProcessHandle process) const;
 
   // Implement |NotificationObserver|.
   virtual void Observe(NotificationType type,
                        const NotificationSource& source,
                        const NotificationDetails& details);
  private:
   // Private constructor.
   MachBroker();
-  ~MachBroker();
+  virtual ~MachBroker();
 
   // True if the listener thread has been started.
   bool listener_thread_started_;
 
   // Used to register for notifications received by NotificationObserver.
   // Accessed only on the UI thread.
   NotificationRegistrar registrar_;
 
   // Stores mach info for every process in the broker.
   typedef std::map<base::ProcessHandle, MachInfo> MachMap;
   MachMap mach_map_;
 
   // Mutex that guards |mach_map_|.
   mutable base::Lock lock_;
 
   friend class MachBrokerTest;
   friend class RegisterNotificationTask;
   // Needed in order to make the constructor private.
   friend struct DefaultSingletonTraits<MachBroker>;
   DISALLOW_COPY_AND_ASSIGN(MachBroker);
 };
 
 #endif  // CHROME_BROWSER_MACH_BROKER_H_
-