Add support for multiple primary icon sizes in list items

Bug: 147509107
Test: Manual

Change-Id: Ie01f5a16b90bed796ffb50ec19b2dbe8194e957d
diff --git a/car-ui-lib/res/drawable/car_ui_list_item_avatar_icon_outline.xml b/car-ui-lib/res/drawable/car_ui_list_item_avatar_icon_outline.xml
new file mode 100644
index 0000000..f8b63f5
--- /dev/null
+++ b/car-ui-lib/res/drawable/car_ui_list_item_avatar_icon_outline.xml
@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2020 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"
+    android:shape="oval">
+</shape>