Adds missing virtual destructors on a couple of interface classes.

chrome/common/ipc_channel.h

 // Copyright (c) 2006-2008 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_IPC_CHANNEL_H__
 #define CHROME_COMMON_IPC_CHANNEL_H__
 
 #include <queue>
 
 #include "base/message_loop.h"
 #include "chrome/common/ipc_message.h"
 
 namespace IPC {
 
 //------------------------------------------------------------------------------
 
 class Channel : public MessageLoopForIO::Watcher,
                 public Message::Sender {
   // Security tests need access to the pipe handle.
   friend class ChannelTest;
 
  public:
   // Implemented by consumers of a Channel to receive messages.
   class Listener {
    public:
+    virtual ~Listener() {}
+
     // Called when a message is received.
     virtual void OnMessageReceived(const Message& message) = 0;
 
     // Called when the channel is connected and we have received the internal
     // Hello message from the peer.
     virtual void OnChannelConnected(int32 peer_pid) {}
 
     // Called when an error is detected that causes the channel to close.
     // This method is not called when a channel is closed normally.
     virtual void OnChannelError() {}
@@ skipping 118 matching lines @@
                                   // to avoid conflicting with normal
                                   // message types, which are enumeration
                                   // constants starting from 0.
   };
 };
 
 }
 
 #endif  // CHROME_COMMON_IPC_CHANNEL_H__