event 'content-scroll' does not show scrolling position

[alfalabs]

Description

While using <paper-scroll-header-panel> the event 'content-scroll' listener function does not show the scrolling position:

 window.addEventListener('content-scroll', function (ev) {
        console.log('event: content-scroll ' + '\nwindow.scrollY = ' + window.scrollY );
 });

Expected outcome

Scrolling position should be available in the listener.
If applicable, a demo of using <paper-scroll-header> with Polymer.IronScrollTargetBehavior should be added to help devs with this problem.

Actual outcome

window.scrollY shows zero all the time while scrolling.

Live Demo

[(https://jsbin.com/hofice/edit?html,console,output)]
The code is an example, link hrefs<link rel="import" href="../../bower_components/paper-scroll-header-panel/paper-scroll-header-panel.html"> are as per my app directory structure.

Browsers Affected

• Chrome
• Firefox
• Safari 9 - Mac not tested
• Safari 8
• Safari 7
• Edge
• IE 11 with window.pageYOffset
• IE 10

[alfalabs]

Please see issue #97