chromium/chrome/android/webapk/shell_apk/res/mipmap-anydpi-v26/ic_launcher.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2017 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
    <background android:drawable="@color/white_adaptive_ic_launcher_background"/>
    <foreground android:drawable="@mipmap/maskable_app_icon"/>
</adaptive-icon>