Amend property evaluation optimization.
Amend property evaluation optimization.

There is code further down in the chain (e.g. setupBuildEnvironment())
that expects the first module instance it finds to contain the right
definition for all its properties. So make sure that is the case.

Change-Id: I55f10d626f5be7ec8502f54e0b1a9673df0b5d93
Reviewed-by: Joerg Bornemann <47777b9406dbddd02a3fdca8341789a013805a11@theqtcompany.com>

villytiger/qbs,gatzka/qt-labs-qbs,qt-labs/qbs,qtproject/qt-labs-qbs,villytiger/qbs,villytiger/qbs,gatzka/qt-labs-qbs,qtproject/qt-labs-qbs,villytiger/qbs,qtproject/qt-labs-qbs,qt-labs/qbs,Distrotech/qbs,villytiger/qbs,qtproject/qt-labs-qbs,qt-labs/qbs,Distrotech/qbs,gatzka/qt-labs-qbs,gatzka/qt-labs-qbs,gatzka/qt-labs-qbs,gatzka/qt-labs-qbs,villytiger/qbs,Distrotech/qbs,Distrotech/qbs,qtproject/qt-labs-qbs,Distrotech/qbs,Distrotech/qbs,qt-labs/qbs,gatzka/qt-labs-qbs,qt-labs/qbs,Distrotech/qbs,qtproject/qt-labs-qbs,qtproject/qt-labs-qbs,qt-labs/qbs,qt-labs/qbs