Add acknowledgement messages for PluginMsg_UpdateGeometry

chrome/plugin/webplugin_proxy.h

 // Copyright (c) 2009 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_PLUGIN_WEBPLUGIN_PROXY_H_
 #define CHROME_PLUGIN_WEBPLUGIN_PROXY_H_
 
 #include <string>
 
 #include "base/hash_tables.h"
@@ skipping 93 matching lines @@
   void HandleURLRequest(const char *method,
                         bool is_javascript_url,
                         const char* target, unsigned int len,
                         const char* buf, bool is_file_data,
                         bool notify, const char* url,
                         intptr_t notify_data, bool popups_allowed);
 
   void UpdateGeometry(const gfx::Rect& window_rect,
                       const gfx::Rect& clip_rect,
                       const TransportDIB::Handle& windowless_buffer,
-                      const TransportDIB::Handle& background_buffer);
+                      const TransportDIB::Handle& background_buffer
+#if defined(OS_MACOSX)
+                      ,
+                      int ack_key
+#endif
+                      );
 
   void CancelDocumentLoad();
 
   void InitiateHTTPRangeRequest(const char* url,
                                 const char* range_info,
                                 intptr_t existing_stream,
                                 bool notify_needed,
                                 intptr_t notify_data);
 
   void SetDeferResourceLoading(int resource_id, bool defer);
@@ skipping 49 matching lines @@
 
 #endif
 
   // Contains the routing id of the host render view.
   int host_render_view_routing_id_;
 
   ScopedRunnableMethodFactory<WebPluginProxy> runnable_method_factory_;
 };
 
 #endif  // CHROME_PLUGIN_WEBPLUGIN_PROXY_H_