Extensions: Send the tab id to platform apps.

chrome/renderer/extensions/dispatcher.h

 // Copyright (c) 2012 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_RENDERER_EXTENSIONS_DISPATCHER_H_
 #define CHROME_RENDERER_EXTENSIONS_DISPATCHER_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 291 matching lines @@
   // them.
   std::map<std::string, BindingInstaller> lazy_bindings_map_;
 
   // Sends API requests to the extension host.
   scoped_ptr<RequestSender> request_sender_;
 
   // The platforms system font family and size;
   std::string system_font_family_;
   std::string system_font_size_;
 
+  // Mapping of port IDs to tabs. If there is no tab, the value would be -1.
+  std::map<int, int> port_to_tab_id_map_;
+
   DISALLOW_COPY_AND_ASSIGN(Dispatcher);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_DISPATCHER_H_