upgrade: only process revlogs that needs it by default We have more and more requirement that does not affect revlog or that only affect some of them. It is silly to force a full processing of all revlog to juste move the requirement around, or to simply rewrite the dirstate. So now, only the revlog that needs to be touched will be touched. Unless the --changelog & al flags are used. Differential Revision: https://phab.mercurial-scm.org/D11871