chromium/chrome/android/java/res/layout/recent_tabs_group_separator_visible.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.
-->

<FrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:paddingTop="@dimen/recent_tabs_visible_separator_padding"
    android:paddingBottom="@dimen/recent_tabs_visible_separator_padding"
    android:paddingStart="16dp"
    android:paddingEnd="16dp" >

    <View
        android:layout_width="match_parent"
        android:layout_height="1px"
        android:background="#e5e5e5" />

</FrameLayout>