[SyncFS] Use nullptr instead of NULL

chrome/browser/sync_file_system/drive_backend/metadata_database.cc

Index: chrome/browser/sync_file_system/drive_backend/metadata_database.cc
diff --git a/chrome/browser/sync_file_system/drive_backend/metadata_database.cc b/chrome/browser/sync_file_system/drive_backend/metadata_database.cc
index 45bd6f837148d1f52bbe059f2f2200f60b3797b4..93b1bbfb8072d772111f16c01675cb46a5c09e1a 100644
--- a/chrome/browser/sync_file_system/drive_backend/metadata_database.cc
+++ b/chrome/browser/sync_file_system/drive_backend/metadata_database.cc
@@ -216,7 +216,7 @@ SyncStatusCode OpenDatabase(const base::FilePath& path,
   options.create_if_missing = true;
   if (env_override)
     options.env = env_override;
-  leveldb::DB* db = NULL;
+  leveldb::DB* db = nullptr;
   leveldb::Status db_status =
       leveldb::DB::Open(options, path.AsUTF8Unsafe(), &db);
   SyncStatusCode status = LevelDBStatusToSyncStatusCode(db_status);
@@ -566,7 +566,7 @@ SyncStatusCode MetadataDatabase::CreateForTesting(
   scoped_ptr<MetadataDatabase> metadata_database(
       new MetadataDatabase(base::FilePath(),
                            enable_on_disk_index,
-                           NULL));
+                           nullptr));
   metadata_database->db_ = db.Pass();
   SyncStatusCode status = metadata_database->Initialize();
   if (status == SYNC_STATUS_OK)
@@ -940,15 +940,15 @@ SyncStatusCode MetadataDatabase::UpdateByDeletedRemoteFileList(
 SyncStatusCode MetadataDatabase::ReplaceActiveTrackerWithNewResource(
     int64 parent_tracker_id,
     const google_apis::FileResource& resource) {
-  DCHECK(!index_->GetFileMetadata(resource.file_id(), NULL));
-  DCHECK(index_->GetFileTracker(parent_tracker_id, NULL));
+  DCHECK(!index_->GetFileMetadata(resource.file_id(), nullptr));
+  DCHECK(index_->GetFileTracker(parent_tracker_id, nullptr));
 
   UpdateByFileMetadata(
       FROM_HERE,
       CreateFileMetadataFromFileResource(GetLargestKnownChangeID(), resource),
       UPDATE_TRACKER_FOR_SYNCED_FILE);
 
-  DCHECK(index_->GetFileMetadata(resource.file_id(), NULL));
+  DCHECK(index_->GetFileMetadata(resource.file_id(), nullptr));
   DCHECK(!index_->GetFileTrackerIDsByFileID(resource.file_id()).has_active());
 
   TrackerIDSet same_path_trackers =
@@ -1077,7 +1077,7 @@ SyncStatusCode MetadataDatabase::UpdateTracker(
                   parent_tracker.tracker_id(),
                   updated_details.title()),
               tracker.file_id(),
-              NULL)) {
+              nullptr)) {
         RemoveFileTracker(tracker.tracker_id(),
                           MARK_NOTHING_DIRTY,
                           index_.get());
@@ -1348,7 +1348,7 @@ SyncStatusCode MetadataDatabase::Initialize() {
 void MetadataDatabase::CreateTrackerForParentAndFileID(
     const FileTracker& parent_tracker,
     const std::string& file_id) {
-  CreateTrackerInternal(parent_tracker, file_id, NULL,
+  CreateTrackerInternal(parent_tracker, file_id, nullptr,
                         UPDATE_TRACKER_FOR_UNSYNCED_FILE);
 }