depends_test phase is needed

[Ryan Schmidt]

On Nov 18, 2010, at 05:30, Anders F Björklund wrote:

> Some ports could use a "depends_test" phase, instead of
> sticking it in depends_build or even worse depends_lib.

I agree. Some ports hack around this by having a "test" variant which must be selected to add the needed dependencies, but having an actual depends_test would be the more correct solution.