Remove base::Value::CreateNullValue

components/history/core/browser/top_sites_impl.cc

 // 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.
 
 #include "components/history/core/browser/top_sites_impl.h"
 
 #include <stdint.h>
 #include <algorithm>
 #include <set>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/md5.h"
+#include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "components/history/core/browser/history_backend.h"
@@ skipping 257 matching lines @@
 
 bool TopSitesImpl::HasBlacklistedItems() const {
   const base::DictionaryValue* blacklist =
       pref_service_->GetDictionary(kMostVisitedURLsBlacklist);
   return blacklist && !blacklist->empty();
 }
 
 void TopSitesImpl::AddBlacklistedURL(const GURL& url) {
   DCHECK(thread_checker_.CalledOnValidThread());
 
-  std::unique_ptr<base::Value> dummy = base::Value::CreateNullValue();
+  auto dummy = base::MakeUnique<base::Value>();
   {
     DictionaryPrefUpdate update(pref_service_, kMostVisitedURLsBlacklist);
     base::DictionaryValue* blacklist = update.Get();
     blacklist->SetWithoutPathExpansion(GetURLHash(url), std::move(dummy));
   }
 
   ResetThreadSafeCache();
   NotifyTopSitesChanged(TopSitesObserver::ChangeReason::BLACKLIST);
 }
 
@@ skipping 585 matching lines @@
     for (std::set<size_t>::reverse_iterator i = indices_to_delete.rbegin();
          i != indices_to_delete.rend(); i++) {
       new_top_sites.erase(new_top_sites.begin() + *i);
     }
     SetTopSites(new_top_sites, CALL_LOCATION_FROM_OTHER_PLACES);
   }
   StartQueryForMostVisited();
 }
 
 }  // namespace history