chromium/components/browser_ui/styles/android/java/res/color/color_primary_with_alpha_20.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2023 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->
<selector xmlns:android="http://schemas.android.com/apk/res/android">
  <item android:alpha="0.2" android:color="?attr/colorPrimary" />
</selector>