[Sync] Replacing NULL with nullptr/null throughout sync code.

chrome/browser/sync/test/integration/sync_app_list_helper.cc

 // Copyright 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 "chrome/browser/sync/test/integration/sync_app_list_helper.h"
 
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/test/integration/sync_datatype_helper.h"
 #include "chrome/browser/sync/test/integration/sync_test.h"
@@ skipping 11 matching lines @@
 using app_list::AppListItemList;
 using app_list::AppListSyncableService;
 using app_list::AppListSyncableServiceFactory;
 
 SyncAppListHelper* SyncAppListHelper::GetInstance() {
   SyncAppListHelper* instance = base::Singleton<SyncAppListHelper>::get();
   instance->SetupIfNecessary(sync_datatype_helper::test());
   return instance;
 }
 
-SyncAppListHelper::SyncAppListHelper() : test_(NULL), setup_completed_(false) {}
+SyncAppListHelper::SyncAppListHelper()
+    : test_(nullptr), setup_completed_(false) {}
 
 SyncAppListHelper::~SyncAppListHelper() {}
 
 void SyncAppListHelper::SetupIfNecessary(SyncTest* test) {
   if (setup_completed_) {
     DCHECK_EQ(test, test_);
     return;
   }
   test_ = test;
   for (auto* profile : test_->GetAllProfiles()) {
@@ skipping 119 matching lines @@
           base::StringPrintf(" Folder Item(%d): ", static_cast<int>(i));
       PrintItem(profile, child, child_label);
     }
     return;
   }
   DVLOG(1) << label << item->ToDebugString()
            << " Page: " << s->GetPageOrdinal(id).ToDebugString().substr(0, 8)
            << " Item: "
            << s->GetAppLaunchOrdinal(id).ToDebugString().substr(0, 8);
 }