Introduce seperate build target for Android TV.

Bug: 68140422
Test: Manually tested that both targets work properly.
Change-Id: Icb1ce0eb91c46d0533e89dce0a92cde3b362e6d7
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 68a3df8..9abc7ef 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -1,3 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+/*
+ * Copyright (C) 2007-2017 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.
+ */
+-->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
         package="com.android.documentsui">