can't read "variant_installed": no such variable

[Joshua Root]

Ryan Schmidt wrote:
> Trying to upgrade rpm51 running MacPorts 1.7 release branch r47786 I get
> this curious message; any ideas? I was able to upgrade other ports (that
> have no variants selected) successfully. Perhaps it has to do with the
> fact that this port has an autoselected platform variant (+macosx) but
> no other variants.
> 
> 
> $ port installed rpm51
> The following ports are currently installed:
>   rpm51 @5.1.6_2+macosx (active)
> $ port -ux upgrade rpm51
> can't read "variant_installed": no such variable
>     while executing
> "ui_debug "$iname
> ${version_installed}_${revision_installed}${variant_installed} is
> installed""

That'd be breakage from r47773. Fixing now.

- Josh