[html-tests] HTML: Fix various bugs in new colSpan/rowSpan tests (#5707)

th was not updated at all, and expected values for IDL sets were not
being computed according to the spec's rules.  This is what comes of
writing tests without an implementation.

This replaces #5706.

View on GitHub: https://github.com/w3c/web-platform-tests/pull/5707

Received on Wednesday, 26 April 2017 18:15:41 UTC