streamclone: remove sleep based "synchronisation" in tests Sleep based test synchronisation does not work. Variation in machine performance and load can make the two process miss their windows. Instead we migrate to explicit signaling through the file system as other tests file are using. Differential Revision: https://phab.mercurial-scm.org/D10478

https://bz.mercurial-scm.org/1089

  $ hg init
  $ mkdir a
  $ echo a > a/b
  $ hg ci -Am m
  adding a/b

  $ hg rm a
  removing a/b
  $ hg ci -m m a

  $ mkdir a b
  $ echo a > a/b
  $ hg ci -Am m
  adding a/b

  $ hg rm a
  removing a/b
  $ cd b

Relative delete:

  $ hg ci -m m ../a

  $ cd ..