tests/test-issue1089.t

hgweb: fallback to checking wsgireq.env for REPO_NAME for 3rd party hosting

Starting with d7fd203e36cc, SCM Manager began to 404 any repository access.
What's happening is that it is generating a python script that creates an hgweb
application (not hgwebdir), and launches hgweb via wsgicgi.  It must be setting
REPO_NAME in the process environment before launching this script, which gets
picked up and put into wsgireq.env when wsgicgi launches the hgweb application.
>From there, other variables (notably 'apppath' and 'dispatchpath') are
constructed differently.

  d7fd203e36cc^ (working):

    apppath: /hg/eng/devsetup
    dispatchpath:
    pathinfo: /eng/devsetup
    reponame: eng/devsetup

  d7fd203e36cc:

    apppath: /hg
    dispatchpath: eng/devsetup
    pathinfo: /eng/devsetup
    reponame: None
    REPO_NAME: eng/devsetup

Rather than having an existing installation break when Mercurial is upgraded,
just resume checking the environment.  I have no idea how many other hosting
solutions would break without restoring this.

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 ..