* RE: BasicEvents.h - our WidgetEvent is not movable (yet), so the change that requires that wasn't included.
* Parts of this use code that was introduced in bug 1427511. For now, they were replaced with their equivalents.
Currently, EventListenerManager calls WidgetEvent::PreventDefault() when the status is nsEventStatus_eConsumeNoDefault.
That causes an unexpected state of events.
To solve this, WidgetEvent should do nothing when it's not cancelable but PreventDefault() is called.