wireproto: client reactor support for receiving frames
We can now feed received frames into the client reactor and it will
validate their sanity, dispatch them appropriately.
The hacky HTTP peer has been updated to use the new code. No
existing tests changed, somewhat proving the code works as
expected.
Rudimentary unit tests for the new functionality have been
implemented.
Differential Revision: https://phab.mercurial-scm.org/D3224
Our full contribution guidelines are in our wiki, please see:
https://www.mercurial-scm.org/wiki/ContributingChanges
If you just want a checklist to follow, you can go straight to
https://www.mercurial-scm.org/wiki/ContributingChanges#Submission_checklist
If you can't run the entire testsuite for some reason (it can be
difficult on Windows), please at least run `contrib/check-code.py` on
any files you've modified and run `python contrib/check-commit` on any
commits you've made (for example, `python contrib/check-commit
273ce12ad8f1` will report some style violations on a very old commit).