Remove base::Value::CreateNullValue

chrome/browser/extensions/api/settings_private/settings_private_delegate.cc

 // Copyright 2015 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 "chrome/browser/extensions/api/settings_private/settings_private_delegate.h"
 
 #include <utility>
 
+#include "base/memory/ptr_util.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/settings/cros_settings.h"
 #include "chrome/browser/extensions/api/settings_private/prefs_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/zoom/chrome_zoom_level_prefs.h"
 #include "chrome/common/pref_names.h"
 #include "components/prefs/pref_service.h"
 #include "content/public/common/page_zoom.h"
 #include "extensions/browser/extension_registry.h"
@@ skipping 10 matching lines @@
 }
 
 SettingsPrivateDelegate::~SettingsPrivateDelegate() {
 }
 
 std::unique_ptr<base::Value> SettingsPrivateDelegate::GetPref(
     const std::string& name) {
   std::unique_ptr<api::settings_private::PrefObject> pref =
       prefs_util_->GetPref(name);
   if (!pref)
-    return base::Value::CreateNullValue();
+    return base::MakeUnique<base::Value>();
   return pref->ToValue();
 }
 
 std::unique_ptr<base::Value> SettingsPrivateDelegate::GetAllPrefs() {
   std::unique_ptr<base::ListValue> prefs(new base::ListValue());
 
   const TypedPrefMap& keys = prefs_util_->GetWhitelistedKeys();
   for (const auto& it : keys) {
     std::unique_ptr<base::Value> pref = GetPref(it.first);
     if (!pref->IsType(base::Value::Type::NONE))
@@ skipping 16 matching lines @@
 }
 
 PrefsUtil::SetPrefResult SettingsPrivateDelegate::SetDefaultZoom(
     double zoom) {
   double zoom_factor = content::ZoomFactorToZoomLevel(zoom);
   profile_->GetZoomLevelPrefs()->SetDefaultZoomLevelPref(zoom_factor);
   return PrefsUtil::SetPrefResult::SUCCESS;
 }
 
 }  // namespace extensions