tests/test-empty-dir.t

localrepository: remove None as default value of path argument in __init__()

The path variable in localrepository.__init__() has a default value None. So
it gives us a option to create an object to localrespository class without
path variable. But things break if you try to do so. The second line in the
init which will be executed when we try to create a localrepository object
will call os.path.expandvars(path) which returns

TypeError: argument of type 'NoneType' is not iterable

I checked occurrences when it is called and can't find any piece of code
which calls it without path variable. Also if something is calling it, its
should break.

  $ hg init

  $ echo 123 > a
  $ hg add a
  $ hg commit -m "first" a

  $ mkdir sub
  $ echo 321 > sub/b
  $ hg add sub/b
  $ hg commit -m "second" sub/b

  $ cat sub/b
  321

  $ hg co 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

  $ cat sub/b 2>/dev/null || echo "sub/b not present"
  sub/b not present

  $ test -d sub || echo "sub not present"
  sub not present