tests/test-extra-filelog-entry.t

windows: use normalized path as path to subrepo

path to subrepo is used to identify or check location of subrepo.

it should be normalized (in "/" delimiter form), because it is also
used with narrowmatcher which uses only normalized path even on
Windows environment.

this patch applies "util.pconvert()" on path to subrepo (called
"subpath") to normalize it.

for this patch, referers of below were checked.

  - subrepo.state()
  - subrepo.itersubrepos()
  - subrepo.subrepo()
  - context.sub()
  - context.substate()

typical usecase is:

    for subpath in ctx.substate:
        sub = ctx.sub(subpath)
        ... ctx.substate[subpath] ....

in this case, normalization has no side effect, because keys given
from substate are used as key itself.

other cases shown below also seem to require subpath to be normalized.

    - path components are joined by "/", in "commands.forget()":

        for subpath in ctx.substate:
            subforget[subpath + '/' + fsub] = (fsub, sub)

    - normalized "file" is used to check below condition, in
      "commands.revert()", "localrepository.commit()", and
      "localrepository._checknested()"

        file in ctx.substate

    - substate.keys() is passed to dirstate.walk()/status() which use
      only normalized pathes

Issue351: mq: qrefresh can create extra revlog entry

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "mq=" >> $HGRCPATH

  $ hg init
  $ hg qinit

  $ echo b > b
  $ hg ci -A -m foo
  adding b

  $ echo cc > b
  $ hg qnew -f foo.diff
  $ echo b > b
  $ hg qrefresh

  $ hg debugindex b
     rev    offset  length   base linkrev nodeid       p1           p2
       0         0       3      0       0 1e88685f5dde 000000000000 000000000000