Progressive disclosure on selected UIs: app, display

Bug: 32255863
Test: RunSettingsRoboTests
Change-Id: I1651433ba30a2b5f880095e07b5e2ed9c4e308b9

res/drawable/ic_arrow_down_24dp.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 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.
+-->
+
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+        android:width="24dp"
+        android:height="24dp"
+        android:viewportWidth="24.0"
+        android:viewportHeight="24.0"
+        android:tint="?android:attr/colorAccent">
+    <path
+        android:fillColor="#FF000000"
+        android:pathData="M7.41,7.84L12,12.42l4.59,-4.58L18,9.25l-6,6 -6,-6z"/>
+</vector>