Fix --repository-url handling for git.

Review Request #2647 — Created Oct. 8, 2011 and submitted — Latest diff uploaded




[ This fixes some problems with This is of particular interest to me, because in my setup there's an upstream SVN repository that I need to access directly with git-svn to commit to it, but we also use a git mirror to share work between those developers who use git. post-review would always try to use the SVN repo directly, but it's better to base the reviews on the github mirror because we can use parent diffs with it. I considered adding a dedicated reviewboard.nosvn setting, but then decided that --repository-url is probably sufficient. ]

Fix --repository-url handling for git.

There were several problems:

(1) If --repository-url was used, post-review failed with
      UnboundLocalError: local variable 'origin_url' reference before

    Fixed by using this code only in the autodetection case.

(2) self.upstream branch wasn't always set, thus failing later.

(3) The parameter was ignored completely when using git-svn.
I am now able to submit patches with --repository-url.