D757: dirstate: move opendirstatefile to dirstatemap

[durham (Durham Goode)]

durham marked an inline comment as done.
durham added inline comments.

INLINE COMMENTS

> indygreg wrote in dirstate.py:1373-1374
> This (pre-existing) error message is pretty bad because typical end users won't have a clue what it means or what to do if they see it.

Agreed.  I'm not even sure what it's actually saying as a mercurial developer...

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D757

To: durham, #hg-reviewers, indygreg
Cc: indygreg, mercurial-devel