chrome/browser/resources/print_preview/settings/layout_settings.html

<div id="layout-settings" class="two-column visible layout-settings">
  <h1 i18n-content="layoutLabel"></h1>
  <div class="right-column">
    <div class="radio"><label>
      <input class="layout-settings-portrait-radio"
             type="radio"
             name="layout"
             checked>
      <span i18n-content="optionPortrait"></span>
    </label></div>
    <div class="radio"><label>
      <input class="layout-settings-landscape-radio"
             type="radio"
             name="layout">
      <span i18n-content="optionLandscape"></span>
    </label></div>
  </div>
</div>