fix build issue on Linux with GCC 4.1.2...

webkit/glue/webplugin_delegate.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 WEBKIT_GLUE_WEBPLUGIN_DELEGATE_H__
 #define WEBKIT_GLUE_WEBPLUGIN_DELEGATE_H__
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/gfx/native_widget_types.h"
 #include "base/gfx/rect.h"
 #include "third_party/npapi/bindings/npapi.h"
 
 typedef struct HDC__* HDC;
 
 class GURL;
 class WebPlugin;
 struct NPObject;
 class WebCursor;
 class WebPluginResourceClient;
 // This is the interface that a plugin implementation needs to provide.
 class WebPluginDelegate {
  public:
   WebPluginDelegate() {}
+  virtual ~WebPluginDelegate() {}
 
   // Initializes the plugin implementation with the given (UTF8) arguments.
   // Note that the lifetime of WebPlugin must be longer than this delegate.
   // If this function returns false the plugin isn't started and shouldn't be
   // called again.  If this method succeeds, then the WebPlugin is valid until
   // PluginDestroyed is called.
   // The load_manually parameter if true indicates that the plugin data would 
   // be passed from webkit. if false indicates that the plugin should download 
   // the data. This also controls whether the plugin is instantiated as a full 
   // page plugin (NP_FULL) or embedded (NP_EMBED)
@@ skipping 77 matching lines @@
                                                         void *notify_data) = 0;
   // Notifies the delegate about a Get/Post URL request getting routed
   virtual void URLRequestRouted(const std::string&url, bool notify_needed, 
                                 void* notify_data) = 0;
  private:
   DISALLOW_EVIL_CONSTRUCTORS(WebPluginDelegate);
 };
 
 #endif  // #ifndef WEBKIT_GLUE_WEBPLUGIN_DELEGATE_H__