Throw error when unfocus fails after clearing element

Author: p0deje

javascript/atoms/action.js

@@ -92,7 +92,13 @@ bot.action.clear = function(element) {
     element.value = '';
     bot.events.fire(element, bot.events.EventType.CHANGE);
     bot.events.fire(element, bot.events.EventType.BLUR);
-    bot.action.LegacyDevice_.focusOnElement(bot.getDocument().body);
+    var body = bot.getDocument().body;
+    if (body) {
+      bot.action.LegacyDevice_.focusOnElement(body);
+    } else {
+      throw new bot.Error(bot.ErrorCode.UNKNOWN_ERROR,
+        'Cannot unfocus element after clearing.');
+    }
   } else if (bot.dom.isElement(element, goog.dom.TagName.INPUT) &&
              (element.getAttribute('type') && element.getAttribute('type').toLowerCase() == "number")) {
     // number input fields that have invalid inputs