[Extensions Bindings] Fix getPlatform() method

extensions/renderer/process_info_native_handler.h

 // Copyright 2014 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 EXTENSIONS_RENDERER_PROCESS_INFO_NATIVE_HANDLER_H_
 #define EXTENSIONS_RENDERER_PROCESS_INFO_NATIVE_HANDLER_H_
 
 #include <string>
 
 #include "extensions/renderer/object_backed_native_handler.h"
@@ skipping 11 matching lines @@
                            bool send_request_disabled);
 
  private:
   void GetExtensionId(const v8::FunctionCallbackInfo<v8::Value>& args);
   void GetContextType(const v8::FunctionCallbackInfo<v8::Value>& args);
   void InIncognitoContext(const v8::FunctionCallbackInfo<v8::Value>& args);
   void IsComponentExtension(const v8::FunctionCallbackInfo<v8::Value>& args);
   void GetManifestVersion(const v8::FunctionCallbackInfo<v8::Value>& args);
   void IsSendRequestDisabled(const v8::FunctionCallbackInfo<v8::Value>& args);
   void HasSwitch(const v8::FunctionCallbackInfo<v8::Value>& args);
+  void GetPlatform(const v8::FunctionCallbackInfo<v8::Value>& args);
 
   std::string extension_id_;
   std::string context_type_;
   bool is_incognito_context_;
   bool is_component_extension_;
   int manifest_version_;
   bool send_request_disabled_;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_RENDERER_PROCESS_INFO_NATIVE_HANDLER_H_