The following should be an underlined italicized "p" as viewed through a narrow slit around
the descender. The "p" is in 12pt size, but is blown up to much larger. This tests that
the text-decoration-skip: ink mask is calculated with more precision than user-space precision.
If we don't have enough precision, there won't be a nice crisp edge on the slope of the underline
where it gets masked off. This test would fail because there would be garbage giant pixel
aliasing near the character. If text-decoration-skip: ink isn't working at all, then the
underline will simply be drawn like normal, and won't match the expected case (where there
is no underline)