Cleanup: Remove more unneeded browser_thread.h includes.

chrome/browser/extensions/event_router_forwarder.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_EVENT_ROUTER_FORWARDER_H_
 #define CHROME_BROWSER_EXTENSIONS_EVENT_ROUTER_FORWARDER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/values.h"
 #include "chrome/browser/profiles/profile.h"
-#include "content/public/browser/browser_thread.h"
 
 class GURL;
 
 namespace extensions {
 
 // This class forwards events to EventRouters.
 // The advantages of this class over direct usage of EventRouters are:
 // - this class is thread-safe, you can call the functions from UI and IO
 //   thread.
 // - the class can handle if a profile is deleted between the time of sending
@@ skipping 71 matching lines @@
 
  private:
   friend class base::RefCountedThreadSafe<EventRouterForwarder>;
 
   DISALLOW_COPY_AND_ASSIGN(EventRouterForwarder);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EVENT_ROUTER_FORWARDER_H_