text-decoration-skip: ink deprecation

[tophf]

Chrome 57 introduced text-decoration-skip: ink to skip glyph descenders for text-decoration: underline.
CSS committee decided to use a separate property text-decoration-skip-ink: auto.
Chrome 64 removed the old property entirely and enabled the new one by default.

This is Chrome-specific as Firefox hasn't yet implemented ink skipping.
I think we should revisit this issue in a year or so (November 2018) and probably remove text-decoration-skip: ink from our pages.