Modify how user repos are cloned.
Modify how user repos are cloned.

This partially reverts bb8a99403, which, it turns out, removed
something that was non-obvious but required.

Add comments explaining why the change is needed so it doesn't
get removed accidentally again.

Change-Id: I2f4129c08a35805598790d3bab7f011181ef910a

jmorse/cyanide,jmorse/cyanide,jmorse/cyanide,jmorse/cyanide