Don't throw from API class.
Don't throw from API class.

s/throw/return, which the author obviously intended to write.

Change-Id: I3093352adecd6e1d7bda52c89d02c57e7dac3b58
Reviewed-by: Joerg Bornemann <47777b9406dbddd02a3fdca8341789a013805a11@digia.com>

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