Affected Version: depot_tools master (?)

What steps will reproduce the problem?
1. Create a branch with its `remote` (as in `git config branch.foo.remote` set to e.g. a SSH repository), tracking a branch from that remote
2. Run `git cl upload` or generally anything that triggers `_GerritChangelistImpl.GetCodereviewServer` in `git_cl.py`

What is the expected output?

An error message that says git is not set up correctly.

What do you see instead?

A `Credentials for the following hosts are required` error message followed with the host just given as `-review` (because `self._GetGitHost()` in `GetCodereviewServer` returns an empty string).