add license header and line break to xml file

src/main/res/drawable/ic_key.xml

@@ -1,8 +1,23 @@
-<!-- drawable/key.xml -->
+<!--
+    @author Google LLC
+    Copyright (C) 2018 Google LLC
+
+    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.
+-->
 <vector xmlns:android="http://schemas.android.com/apk/res/android"
     android:height="24dp"
     android:width="24dp"
     android:viewportWidth="24"
     android:viewportHeight="24">
     <path android:fillColor="#FFF" android:pathData="M7,14A2,2 0 0,1 5,12A2,2 0 0,1 7,10A2,2 0 0,1 9,12A2,2 0 0,1 7,14M12.65,10C11.83,7.67 9.61,6 7,6A6,6 0 0,0 1,12A6,6 0 0,0 7,18C9.61,18 11.83,16.33 12.65,14H17V18H21V14H23V10H12.65Z" />
-</vector>
+</vector>