Modify extension request IPC messages to pass a ListValue instead of a string.

chrome/browser/tab_contents/tab_contents.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_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_
 #define CHROME_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_
 
 #include "build/build_config.h"
 
 #include <map>
@@ skipping 855 matching lines @@
   virtual void UpdateInspectorSettings(const std::string& raw_settings);
   virtual void Close(RenderViewHost* render_view_host);
   virtual void RequestMove(const gfx::Rect& new_bounds);
   virtual void DidStartLoading(RenderViewHost* render_view_host);
   virtual void DidStopLoading(RenderViewHost* render_view_host);
   virtual void RequestOpenURL(const GURL& url, const GURL& referrer,
                               WindowOpenDisposition disposition);
   virtual void DomOperationResponse(const std::string& json_string,
                                     int automation_id);
   virtual void ProcessDOMUIMessage(const std::string& message,
-                                   const std::string& content,
+                                   const Value* content,
                                    int request_id,
                                    bool has_callback);
   virtual void ProcessExternalHostMessage(const std::string& message,
                                           const std::string& origin,
                                           const std::string& target);
   virtual void RunFileChooser(bool multiple_files,
                               const string16& title,
                               const FilePath& default_file);
   virtual void RunJavaScriptMessage(const std::wstring& message,
                                     const std::wstring& default_prompt,
@@ skipping 272 matching lines @@
 
   // The time that we started to create the new tab page.
   base::TimeTicks new_tab_start_time_;
 
   // ---------------------------------------------------------------------------
 
   DISALLOW_COPY_AND_ASSIGN(TabContents);
 };
 
 #endif  // CHROME_BROWSER_TAB_CONTENTS_TAB_CONTENTS_H_