py-pyqt4: fix for the depends_lib reset caused by the Python PortGroup

[René J.V. Bertin]

On Sunday December 18 2016 04:38:30 Joshua Root wrote:

> py-pyqt4 doesn't need qt4-mac.

Correct.

> The python portgroup's behaviour is correct.


In this case it has the appropriate side-effect, but that doesn't make the behaviour right.
It's not up to an essentially random portgroup to decide whether or not the port including it needs Qt4 or any other dependency that might already have been declared. If a port doesn't require a given dependency it shouldn't include portgroups that declare that dependency.

R.