[Sync] Removing duplicated includes between cc and h files.

components/sync/base/weak_handle.cc

 // 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.
 
 #include "components/sync/base/weak_handle.h"
 
 #include <sstream>
 
 #include "base/callback.h"
-#include "base/location.h"
 #include "base/threading/thread_task_runner_handle.h"
 
 namespace syncer {
 
 namespace internal {
 
 WeakHandleCoreBase::WeakHandleCoreBase()
     : owner_loop_task_runner_(base::ThreadTaskRunnerHandle::Get()) {}
 
 bool WeakHandleCoreBase::IsOnOwnerThread() const {
   return owner_loop_task_runner_->BelongsToCurrentThread();
 }
 
 WeakHandleCoreBase::~WeakHandleCoreBase() {}
 
 void WeakHandleCoreBase::PostToOwnerThread(
     const tracked_objects::Location& from_here,
     const base::Closure& fn) const {
   if (!owner_loop_task_runner_->PostTask(from_here, fn)) {
     DVLOG(1) << "Could not post task from " << from_here.ToString();
   }
 }
 
 }  // namespace internal
 
 }  // namespace syncer