Do some common processing on some arguments in QCM.
Do some common processing on some arguments in QCM.

Clearing error maps, setting BadArgumentErrors etc.

enthought/qt-mobility,kaltsi/qt-mobility,qtproject/qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,KDE/android-qt-mobility,tmcguire/qt-mobility,qtproject/qt-mobility,tmcguire/qt-mobility,KDE/android-qt-mobility,enthought/qt-mobility,qtproject/qt-mobility,tmcguire/qt-mobility,kaltsi/qt-mobility,kaltsi/qt-mobility,tmcguire/qt-mobility,qtproject/qt-mobility,kaltsi/qt-mobility,KDE/android-qt-mobility,enthought/qt-mobility,enthought/qt-mobility,tmcguire/qt-mobility,qtproject/qt-mobility,KDE/android-qt-mobility,enthought/qt-mobility,kaltsi/qt-mobility,kaltsi/qt-mobility