Only stopPropagation if has srcElement attribute

@soyjavi · @soyjavi · commit a1fd0039f321 · 2014-06-12T14:53:33.000+02:00
diff --git a/source/quo.gestures.coffee b/source/quo.gestures.coffee
@@ -32,7 +32,7 @@ Quo.Gestures = do ($$ = Quo) ->
 
   # Private methods
   _start = (ev) ->
-    return ev.stopPropagation() if ev.srcElement.tagName.toLowerCase() in _disabled_tags
+    return ev.stopPropagation() if ev.srcElement?.tagName.toLowerCase() in _disabled_tags
     _started = true
     _originalEvent = ev or event
     _fingers = _getFingers(ev)
