chromium/chrome/browser/ui/android/night_mode/java/res/layout/radio_button_group_theme_preference.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
Copyright 2019 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:focusable="false">
    <org.chromium.components.browser_ui.widget.RadioButtonWithDescriptionLayout
        android:id="@+id/radio_button_layout"
        android:layout_width="match_parent"
        android:layout_height="match_parent">

      <org.chromium.components.browser_ui.widget.RadioButtonWithDescription
          android:id="@+id/system_default"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          app:primaryText="@string/themes_system_default_title"
          app:descriptionText="@string/themes_system_default_summary" />

      <!-- override default padding top and bottom -->
      <org.chromium.components.browser_ui.widget.RadioButtonWithDescription
          android:id="@+id/light"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:minHeight="@dimen/min_touch_target_size"
          android:paddingTop="8dp"
          android:paddingBottom="8dp"
          app:primaryText="@string/light_mode" />

      <org.chromium.components.browser_ui.widget.RadioButtonWithDescription
          android:id="@+id/dark"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:minHeight="@dimen/min_touch_target_size"
          android:paddingTop="8dp"
          android:paddingBottom="8dp"
          app:primaryText="@string/dark_mode" />

    </org.chromium.components.browser_ui.widget.RadioButtonWithDescriptionLayout>

    <!-- Make the row clickable -->
    <LinearLayout
        android:id="@+id/checkbox_container"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:minHeight="@dimen/min_touch_target_size"
        android:gravity="center_vertical"
        android:clickable="true"
        android:focusable="true"
        android:paddingStart="@dimen/radio_button_accessory_view_padding_start"
        android:paddingEnd="@dimen/radio_button_accessory_view_padding_end"
        android:visibility="gone"
        android:background="?attr/selectableItemBackground">

        <CheckBox
            android:id="@+id/darken_websites"
            android:clickable="false"
            android:focusable="false"
            android:layout_marginEnd="@dimen/theme_preferences_checkbox_margin_end"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/darken_websites"
            android:textAppearance="@style/TextAppearance.TextLarge.Primary" />
    </LinearLayout>
</LinearLayout>