unbundle: acquire 'wlock' when processing bundle2 (BC) (issue4596)
A bundle2 may contain bookmark updates (or other extension content) that
requires the 'wlock' to be written. As 'wlock' must be acquired before 'lock',
we must stay on the side of caution and use both in all case to ensure their
ordering.
$ cat > unix2mac.py <<EOF
> import sys
>
> for path in sys.argv[1:]:
> data = file(path, 'rb').read()
> data = data.replace('\n', '\r')
> file(path, 'wb').write(data)
> EOF
$ cat > print.py <<EOF
> import sys
> print(sys.stdin.read().replace('\n', '<LF>').replace('\r', '<CR>').replace('\0', '<NUL>'))
> EOF
$ hg init
$ echo '[hooks]' >> .hg/hgrc
$ echo 'pretxncommit.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
$ echo 'pretxnchangegroup.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
$ cat .hg/hgrc
[hooks]
pretxncommit.cr = python:hgext.win32text.forbidcr
pretxnchangegroup.cr = python:hgext.win32text.forbidcr
$ echo hello > f
$ hg add f
$ hg ci -m 1
$ python unix2mac.py f
$ hg ci -m 2
attempt to commit or push text file(s) using CR line endings
in dea860dc51ec: f
transaction abort!
rollback completed
abort: pretxncommit.cr hook failed
[255]
$ hg cat f | python print.py
hello<LF>
$ cat f | python print.py
hello<CR>