Although many things are private, the urls of the infra_internal and
build_internal repositories are not. So let's just add a fetch recipe
for them anyway.

R=iannucci@chromium.org

Review URL: https://codereview.chromium.org/544863006

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@292586 0039d316-1c4b-4281-b951-d872f2087c98