Currently no functional change but public API breaks should come early.
The thread state object will be used for looking up thread specific
codebuffers in the future when we support MDWE with code mirrors.
It is not an external component, and it makes paths needlessly long.
Ryan seemed amenable to this when we discussed on IRC earlier.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Paulo Matos