components: Cleanup class/struct fwd declarations

components/gcm_driver/gcm_profile_service.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 COMPONENTS_GCM_DRIVER_GCM_PROFILE_SERVICE_H_
 #define COMPONENTS_GCM_DRIVER_GCM_PROFILE_SERVICE_H_
 
 #include <memory>
 #include <string>
 
 #include "base/callback_forward.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "build/build_config.h"
 #include "components/keyed_service/core/keyed_service.h"
 #include "components/signin/core/browser/profile_identity_provider.h"
 #include "components/version_info/version_info.h"
 
 class PrefService;
-class ProfileOAuth2TokenService;
-class SigninManagerBase;
 
 namespace base {
 class SequencedTaskRunner;
 }
 
 namespace net {
 class URLRequestContextGetter;
 }
 
-namespace user_prefs {
-class PrefRegistrySyncable;
-}
-
 namespace gcm {
 
 class GCMClientFactory;
 class GCMDriver;
 
-#if defined(OS_CHROMEOS)
-class GCMConnectionObserver;
-#endif
-
 // Providing GCM service, via GCMDriver.
 class GCMProfileService : public KeyedService {
  public:
 #if defined(OS_ANDROID)
   GCMProfileService(
       base::FilePath path,
       scoped_refptr<base::SequencedTaskRunner>& blocking_task_runner);
 #else
   GCMProfileService(
       PrefService* prefs,
@@ skipping 36 matching lines @@
   std::unique_ptr<IdentityObserver> identity_observer_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(GCMProfileService);
 };
 
 }  // namespace gcm
 
 #endif  // COMPONENTS_GCM_DRIVER_GCM_PROFILE_SERVICE_H_