chromium/chrome/browser/download/internal/android/java/res/drawable/circular_progress_bar_determinate_large.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2018 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
    <item android:id="@android:id/progress">
        <rotate
            android:fromDegrees="270"
            android:toDegrees="270" >
            <shape
                android:innerRadius="28dp"
                android:thickness="2dp"
                android:useLevel="true"
                android:shape="ring">
                <gradient
                    android:startColor="@color/modern_grey_900"
                    android:endColor="@color/modern_grey_900"
                    android:type="sweep" />
            </shape>
        </rotate>
    </item>
</layer-list>