Screen reader text needs to reset word-wrap

[afercia]

Turns out some CSS properties, especially the ones related to text rendering, may affect the way screen readers announce content. Reported by Sebastien Massy from the Accessibility testers group:

"In Firefox/Orca/Linux all text belonging to this class ends up being stretched out to one letter per line of the virtual buffer, presumably in an attempt to represent the text as it would appear if formatted according to the class. The end result is that using down or up arrow to scroll rapidly through a list of posts (or any other list employing this class) is at best tedious and at worst impossible. Chrome/ChromeVox, which tends to promote structural navigation over layout reproduction does not exhibit this problem."

I can't test with Orca, but I've noticed similar issues with Firefox + NVDA. The screen-reader-text rule may inherit properties from other CSS rules, for example in the list tables, see screenshot:

The word-wrap: break-word; CSS declaration forces NVDA to ignore spaces between words, notice how text is read out in the NVDA Speech Viewer in the screenshot below:

When resetting word-wrap, NVDA honors the space between words, see screenshot:

I wouldn't be surprised if this was also the reason why Orca reads out content one letter per line, because that's what "visually" happens when applying word-wrap: break-word; on an element with a size of 1px x 1px:

Linux + Firefox + Orca testers welcome.

The proposed patch resets the word-wrap property. Uses !important to keep it simple and because screen-reader-text is a utility rule not meant to be overridden.

[afercia]

screen-reader-text: reset inherited word-wrap, see widefat tables

[afercia]

While can't test with Orca, tested again with NVDA and this patch is an improvement, see the "NVDA Speech Viewer" in the screenshot above. Seems it's not breaking anything, after all what it does is resetting a property that shouldn't be used by screen-reader-text in the first place. Would recommend for commit consideration.

[helen]

In 32509:

Accessibility: Ensure screen reader text is read as words and not affected by word-wrap.

props afercia.
fixes #31962.