[ttml2] Pull Request: Emphasize null style semantics in context of ruby container spans (#1100).

skynavga has just submitted a new pull request for https://github.com/w3c/ttml2:

== Emphasize null style semantics in context of ruby container spans (#1100). ==
Closes #1100.

See https://github.com/w3c/ttml2/pull/1101

Received on Sunday, 26 May 2019 20:16:12 UTC