In 8a7195d6b9557cc57061d18d5a643a424ff44f72, as part of the fix for T66901: Paragraph wrapping bug, I introduced a bug for the following test case:
[subbu@earth parsoid] echo '<span><div>x</div></span>' | parse.js --normalize <p></p> <div>x</div> <p></p>
whereas PHP Parser + tidy combo only generates
<span><div>x</div></span>
The p-tags are introduce only when there is content after the <span> or before the </span> tags. So, my p-wrapper fix overreached a bit.
This is now introducing another set of false positives in T176363