Element.visible returns falsy true in IE8

[jwestbrook]

previous lighthouse ticket #3509
by Andriy Godovanets

---

Prototype 1.7.1
IE8

Create CSS class
.hidden { display:none !important; }

set this class to HTML element
Issue:
$("test").visible() === true

The problem in visible method implementation:

function visible(element) {
return $(element).style.display !== 'none';
}
This could be fixed to something like

function visible(element) {
return getRawStyle($(element), "display") !== 'none';
}
but getRawStyle function located in other space