handle case where element doesn't have a type attribute

Author: lukeis

javascript/atoms/action.js

@@ -92,7 +92,7 @@ bot.action.clear = function(element) {
     element.value = '';
     bot.events.fire(element, bot.events.EventType.CHANGE);
   } else if (bot.dom.isElement(element, goog.dom.TagName.INPUT) &&
-             element.getAttribute('type').toLowerCase() == "number") {
+             (element.getAttribute('type') && element.getAttribute('type').toLowerCase() == "number")) {
     // number input fields that have invalid inputs
     // report their value as empty string with no way to tell if there is a
     // current value or not