returntype">void</span>
            <span class="name ">allowCustomElement</span>(
            <br>
            <div class="parameters">
                <span class="parameter" id="allowCustomElement-param-tagName"><span class="type-annotation">String</span> <span class="parameter-name">tagName</span></span>,<br>{<span class="parameter" id="allowCustomElement-param-uriPolicy"><span class="type-annotation"><a href="polymer_app_layout/UriPolicy-class.html">UriPolicy</a></span> <span class="parameter-name">uri