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

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2016 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"
    android:exitFadeDuration="@android:integer/config_mediumAnimTime">
    <item android:state_pressed="true" android:drawable="@color/bookmark_widget_pressed_highlight" />
    <item android:drawable="@android:color/transparent" />
</selector>