[SyncFS] Use nullptr instead of NULL

chrome/browser/sync_file_system/drive_backend/sync_task_manager.h

Index: chrome/browser/sync_file_system/drive_backend/sync_task_manager.h
diff --git a/chrome/browser/sync_file_system/drive_backend/sync_task_manager.h b/chrome/browser/sync_file_system/drive_backend/sync_task_manager.h
index 0236016a77e08e82fb0ebd3752c0f8b28fe79f6f..2bc67670f4213064bf1bec8dcb1e6284e9d62532 100644
--- a/chrome/browser/sync_file_system/drive_backend/sync_task_manager.h
+++ b/chrome/browser/sync_file_system/drive_backend/sync_task_manager.h
@@ -163,7 +163,7 @@ class SyncTaskManager : public base::SupportsWeakPtr<SyncTaskManager> {
                scoped_ptr<SyncTask> task);
 
   // Runs a pending task as a foreground task if possible.
-  // If |token| is non-NULL, put |token| back to |token_| beforehand.
+  // If |token| is non-nullptr, put |token| back to |token_| beforehand.
   void MaybeStartNextForegroundTask(scoped_ptr<SyncTaskToken> token);
 
   base::WeakPtr<Client> client_;