windowToggle bug in WindowToggleSubscriber#closeWindow

[staltz]

RxJS version: 5.0.0-beta.2

Code to reproduce:

var clicks = Rx.Observable.fromEvent(document, 'click');
var openings = Rx.Observable.interval(1000);
var result = clicks.windowToggle(openings, i =>
  i % 2 ? Rx.Observable.interval(500) : Rx.Observable.empty()
).mergeAll();
result.subscribe(x => console.log(x));

Expected behavior:
No error thrown, some messages in the console when the user clicks.

Actual behavior:
Uncaught TypeError: Cannot read property 'window' of undefined after 1 second.

Additional information:
Seems to happen in WindowToggleSubscriber#closeWindow.

JSBin: http://jsbin.com/zenelokita/1/edit?html,js,output

[benlesh]

Good catch