A bug was introduced together with the FixedQueue implementation for
process.nextTick which meant that the queue wouldn't necessarily
fully clear on each run through. Fix it and abstract the data
structure into an internal module that can later be used elsewhere.
PR-URL: https://github.com/nodejs/node/pull/20468
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
