nt lang-dart">readystatechange</code> events to event
handlers that are not necessarily instances of <a href="polymer_app_layout/HttpRequest-class.html">HttpRequest</a>.
            </dd>
            <dt id="UNSENT" class="constant">
                <span class="top-level-variable-type">int</span>
                <span class="name "><a href="polymer_app_layout/HttpRequest/UNSENT.html">UNSENT</a></span>
                =
                <span class="constant-value">0</span>
            </dt>
            <dd>