Add a missing license header

Change-Id: I16202391cecc80852e55d9a6409234f25aa7d946

polygerrit-ui/app/scripts/gr-display-name-utils/gr-display-name-utils.js

@@ -1,3 +1,19 @@
+/**
+ * @license
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 (function(window) {
   'use strict';