chrome: Cleanup class/struct forward declarations

chrome/browser/renderer_host/pepper/device_id_fetcher.h

 // Copyright (c) 2013 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_RENDERER_HOST_PEPPER_DEVICE_ID_FETCHER_H_
 #define CHROME_BROWSER_RENDERER_HOST_PEPPER_DEVICE_ID_FETCHER_H_
 
 #include <stdint.h>
 
 #include <string>
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "ppapi/c/pp_instance.h"
 
-class Profile;
-
-namespace content {
-class BrowserPpapiHost;
-}
-
 namespace user_prefs {
 class PrefRegistrySyncable;
 }
 
 namespace chrome {
 
 // This class allows asynchronously fetching a unique device ID. The callback
 // passed in when calling Start() will be called when the ID has been fetched
 // or on error.
 class DeviceIDFetcher : public base::RefCountedThreadSafe<DeviceIDFetcher> {
@@ skipping 41 matching lines @@
   bool in_progress_;
 
   int render_process_id_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceIDFetcher);
 };
 
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_PEPPER_DEVICE_ID_FETCHER_H_