Take extensions out of Profile into a profile-keyed service, ExtensionSystem.

chrome/browser/extensions/extension_function_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_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_DISPATCHER_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_DISPATCHER_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/profiles/profile.h"
 #include "ipc/ipc_message.h"
 #include "googleurl/src/gurl.h"
 
 class Browser;
 class ChromeRenderMessageFilter;
 class Extension;
 class ExtensionFunction;
+class ExtensionInfoMap;
 class Profile;
 class RenderViewHost;
 struct ExtensionHostMsg_Request_Params;
 
 namespace content {
 class WebContents;
 }
 
 namespace extensions {
 class ProcessMap;
@@ skipping 103 matching lines @@
   static void SendAccessDenied(IPC::Message::Sender* ipc_sender,
                                int routing_id,
                                int request_id);
 
   Profile* profile_;
 
   Delegate* delegate_;
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_DISPATCHER_H_