evil-hit-sender.js

function onUnload()
{
  var timeout = 300; // maximum time to hold up the page 

  var nonInteraction; // interaction code not included for brevity

  var skip = false

  var data = {
    eventCategory: 'Category',
    eventAction: 'Action',
    eventLabel: (everScrolled) ? 'Did Scroll' : 'No Scroll',
    eventValue: reach,
    nonInteraction: nonInteraction,
    hitCallback: function(){
      skip = true
    }
  }

  // send hit
  ga('send', 'event', data)

  // evilness
  if (timeout && !window.navigator.sendBeacon){
    var start = new Date()
    var run = 0
    do {
      run = new Date() - start

    } while (run < timeout && !skip)

  }

}