tests/test-revert-unknown.t

tests: prepare rebase test for wc parent preservation

In the way to solving issue3813 we'll preserve the working directory parent
after the rebase. Multiple rebases test expect the working directory parent to
be tip after rebase. We patches them before the actual change to prevent
confusion.

  $ hg init
  $ touch unknown

  $ touch a
  $ hg add a
  $ hg ci -m "1"

  $ touch b
  $ hg add b
  $ hg ci -m "2"

Should show unknown

  $ hg status
  ? unknown
  $ hg revert -r 0 --all
  removing b

Should show unknown and b removed

  $ hg status
  R b
  ? unknown

Should show a and unknown

  $ ls
  a
  unknown