Remove unused linked_ptr inclusion

components/sync/engine_impl/sync_scheduler_impl.h

 // Copyright 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 COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_IMPL_H_
 #define COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_IMPL_H_
 
 #include <map>
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/cancelable_callback.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
-#include "base/memory/linked_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/threading/non_thread_safe.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "components/sync/base/weak_handle.h"
 #include "components/sync/engine/polling_constants.h"
 #include "components/sync/engine_impl/cycle/nudge_tracker.h"
 #include "components/sync/engine_impl/cycle/sync_cycle.h"
 #include "components/sync/engine_impl/cycle/sync_cycle_context.h"
 #include "components/sync/engine_impl/net/server_connection_manager.h"
@@ skipping 269 matching lines @@
   // A second factory specially for weak_handle_this_, to allow the handle
   // to be const and alleviate threading concerns.
   base::WeakPtrFactory<SyncSchedulerImpl> weak_ptr_factory_for_weak_handle_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncSchedulerImpl);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_IMPL_SYNC_SCHEDULER_IMPL_H_