After adding an import of socket-types.js to call-keyserver-endpoint-provider.js in a later diff, I encountered an import cycle that was triggered by yarn test in lib.
I found a way to resolve it by extracting the rawThreadInfo validators into their own file. Now it's possible to import the rawThreadInfo validators without triggering an import of threadEntityValidator from entity-text.js. I didn't follow the mystery further than that... entity-text.js imports a lot of utils, so I guessed that this change would solve the issue.
NOTE: I also renamed MemberInfoValidator to memberInfoValidator here, for consistency with the rest of the codebase.
NOTE: I ended up having another import cycle that I had to resolve, and after resolving that one, this diff was no longer necessary to resolve the first import cycle. That said, I still thought it was a good idea to put this diff up, in case the same code is involved in another import cycle later.
Depends on D10952