chrome/android/java/res/layout/bottom_toolbar_menu_button.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright 2019 The Chromium Authors. All rights reserved.
     Use of this source code is governed by a BSD-style license that can be
     found in the LICENSE file. -->
<org.chromium.chrome.browser.toolbar.MenuButton
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:clickable="true"
    android:contentDescription="@string/accessibility_toolbar_btn_menu"
    android:id="@+id/menu_button_wrapper">

    <org.chromium.ui.widget.ChromeImageButton
        android:id="@+id/menu_button"
        style="@style/SplitToolbarButton"
        android:src="@drawable/ic_more_vert_24dp"
        android:importantForAccessibility="no"
        android:layout_gravity="center"
        android:background="?attr/selectableItemBackgroundBorderless"
        app:tint="@color/default_icon_color_tint_list" />

    <ImageView
        android:id="@+id/menu_badge"
        style="@style/SplitToolbarButton"
        android:src="@drawable/badge_update_dark"
        tools:ignore="ContentDescription"
        android:background="?attr/selectableItemBackgroundBorderless"
        android:importantForAccessibility="no"
        android:layout_gravity="center"
        android:visibility="invisible" />

</org.chromium.chrome.browser.toolbar.MenuButton>