[SyncFS] Use nullptr instead of NULL

chrome/browser/sync_file_system/drive_backend/metadata_database_unittest.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_file_system/drive_backend/metadata_database.h"
 
 #include "base/bind.h"
 #include "base/files/scoped_temp_dir.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 214 matching lines @@
       if (!file->tracker_only)
         EXPECT_TRUE(PutFileToDB(db.get(), file->metadata).ok());
       EXPECT_TRUE(PutTrackerToDB(db.get(), file->tracker).ok());
     }
   }
 
   void VerifyTrackedFile(const TrackedFile& file) {
     if (!file.should_be_absent) {
       if (file.tracker_only) {
         EXPECT_FALSE(metadata_database()->FindFileByFileID(
-            file.metadata.file_id(), NULL));
+            file.metadata.file_id(), nullptr));
       } else {
         VerifyFile(file.metadata);
       }
       VerifyTracker(file.tracker);
       return;
     }
 
     EXPECT_FALSE(metadata_database()->FindFileByFileID(
-        file.metadata.file_id(), NULL));
+        file.metadata.file_id(), nullptr));
     EXPECT_FALSE(metadata_database()->FindTrackerByTrackerID(
-        file.tracker.tracker_id(), NULL));
+        file.tracker.tracker_id(), nullptr));
   }
 
   void VerifyTrackedFiles(const TrackedFile** tracked_files, int size) {
     for (int i = 0; i < size; ++i)
       VerifyTrackedFile(*tracked_files[i]);
   }
 
   MetadataDatabase* metadata_database() { return metadata_database_.get(); }
 
   scoped_ptr<LevelDBWrapper> InitializeLevelDB() {
-    leveldb::DB* db = NULL;
+    leveldb::DB* db = nullptr;
     leveldb::Options options;
     options.create_if_missing = true;
     options.max_open_files = 0;  // Use minimum.
     options.env = in_memory_env_.get();
     leveldb::Status status =
         leveldb::DB::Open(options, database_dir_.path().AsUTF8Unsafe(), &db);
     EXPECT_TRUE(status.ok());
 
     scoped_ptr<LevelDBWrapper> wrapper(new LevelDBWrapper(make_scoped_ptr(db)));
 
@@ skipping 866 matching lines @@
   };
 
   SetUpDatabaseByTrackedFiles(tracked_files, arraysize(tracked_files));
   EXPECT_EQ(SYNC_STATUS_OK, InitializeMetadataDatabase());
   VerifyTrackedFiles(tracked_files, arraysize(tracked_files));
 
   scoped_ptr<base::ListValue> files =
       metadata_database()->DumpFiles(app_root.tracker.app_id());
   ASSERT_EQ(2u, files->GetSize());
 
-  base::DictionaryValue* file = NULL;
+  base::DictionaryValue* file = nullptr;
   std::string str;
 
   ASSERT_TRUE(files->GetDictionary(0, &file));
   EXPECT_TRUE(file->GetString("title", &str) && str == "folder_0");
   EXPECT_TRUE(file->GetString("type", &str) && str == "folder");
   EXPECT_TRUE(file->HasKey("details"));
 
   ASSERT_TRUE(files->GetDictionary(1, &file));
   EXPECT_TRUE(file->GetString("title", &str) && str == "file_0");
   EXPECT_TRUE(file->GetString("type", &str) && str == "file");
   EXPECT_TRUE(file->HasKey("details"));
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system