chromium/chrome/android/java/res/drawable/button_borderless_compat.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2015 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<ripple xmlns:android="http://schemas.android.com/apk/res/android"
    android:color="?android:attr/colorControlHighlight">
    <item android:id="@android:id/mask"
          android:drawable="@drawable/button_compat_shape" />
</ripple>