SIA-R66 and R69 should ignore text that has been made invisible

[Jym77]

<div style="background-image: url'(foo.jpg'); text-indent: -10000px">Hello</div>

The element is visible because of its background image, and has a size (if sized). However, its text is invisible. In that case, we do consider that the element being visible, its text also is.

• Follow up on II-7222

[hartle-tech]

!pr help