applicationSuite.SetUpTest cannot make store

[Curtis Hovey]

As seen at
    http://reports.vapour.ws/releases/issue/58ca8a12749a5671923c2b15

application_test.go:69:
    s.CharmStoreSuite.SetUpTest(c)
c:/users/admini~1/appdata/local/temp/tmpnnau3o/gogo/src/github.com/juju/juju/apiserver/testing/fakecharmstore.go:59:
    c.Assert(err, jc.ErrorIsNil)
... value *errgo.Err = [{c:/users/admini~1/appdata/local/temp/tmpnnau3o/gogo/src/gopkg.in/juju/charmstore.v5-unstable/internal/charmstore/server.go:131: cannot make store}

[Anastasia (anastasia-macmood)]

It's a pity that this link no longer works, pasting offending stack trace would have been so much more lasting.

We have done some work around faking charm store in our testing... maybe not enough \o/ but:

* I cannot reproduce this failure locally under stress and after hundreds of runs;
* I cannot see the original failure;
* We have not seen this failure for years in our CI.

I am marking this as Fix Released.