Merge "Add background to app chip menu so elevation shadow renders." into main

quickstep/res/layout/icon_app_chip_view.xml

@@ -23,6 +23,7 @@
     android:focusable="false"
     android:importantForAccessibility="no"
     android:autoMirrored="true"
+    android:background="@drawable/icon_menu_elevation_background"
     android:elevation="@dimen/task_thumbnail_icon_menu_elevation" >
 
     <ImageView

quickstep/res/values/dimens.xml

@@ -88,7 +88,7 @@
     <dimen name="task_thumbnail_icon_menu_drawable_max_size">32dp</dimen>
     <!--  The size of the icon menu's icon touch target  -->
     <dimen name="task_thumbnail_icon_menu_drawable_touch_size">44dp</dimen>
-    <dimen name="task_thumbnail_icon_menu_elevation">14dp</dimen>
+    <dimen name="task_thumbnail_icon_menu_elevation">4dp</dimen>
 
     <dimen name="task_icon_cache_default_icon_size">72dp</dimen>
     <item name="overview_modal_max_scale" format="float" type="dimen">1.1</item>

res/drawable/icon_menu_elevation_background.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+     Copyright (C) 2023 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.
+-->
+<shape xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:androidprv="http://schemas.android.com/apk/prv/res/android"
+    android:shape="rectangle">
+    <solid android:color="?androidprv:attr/materialColorSurfaceBright" />
+    <corners android:radius="@dimen/task_thumbnail_icon_menu_corner_radius" />
+</shape>