Virtual destructors should have virtual keyword.

content/plugin/webplugin_proxy.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 CONTENT_PLUGIN_WEBPLUGIN_PROXY_H_
 #define CONTENT_PLUGIN_WEBPLUGIN_PROXY_H_
 #pragma once
 
 #include <string>
 
@@ skipping 30 matching lines @@
 // renderer.
 class WebPluginProxy : public webkit::npapi::WebPlugin {
  public:
   // Creates a new proxy for WebPlugin, using the given sender to send the
   // marshalled WebPlugin calls.
   WebPluginProxy(PluginChannel* channel,
                  int route_id,
                  const GURL& page_url,
                  gfx::NativeViewId containing_window,
                  int host_render_view_routing_id);
-  ~WebPluginProxy();
+  virtual ~WebPluginProxy();
 
   void set_delegate(webkit::npapi::WebPluginDelegateImpl* d) { delegate_ = d; }
 
   // WebPlugin overrides
   virtual void SetWindow(gfx::PluginWindowHandle window);
 
   // Whether input events should be sent to the delegate.
   virtual void SetAcceptsInputEvents(bool accepts);
 
   virtual void WillDestroyWindow(gfx::PluginWindowHandle window);
@@ skipping 154 matching lines @@
 
 #endif
 
   // Contains the routing id of the host render view.
   int host_render_view_routing_id_;
 
   ScopedRunnableMethodFactory<WebPluginProxy> runnable_method_factory_;
 };
 
 #endif  // CONTENT_PLUGIN_WEBPLUGIN_PROXY_H_