In the ECMAScript DOM binding, the ECMAScript
native Function type must implement the
EventListener interface such that invoking the
handleEvent() method of that interface on the object from
another language binding invokes the function itself, with the
event argument as its only argument. In the ECMAScript
binding itself, however, the handleEvent() method of the
interface is not directly accessible on Function objects.
Such functions, when invoked, must be called in the scope of the browsing context that they were created in.
