don't call the backend for invalid frontend objects (a frontend object is !isValid() if there's no backend object, and none can be created)
don't call the backend for invalid frontend objects (a frontend object is !isValid() if there's no backend object, and none can be created)

svn path=/trunk/KDE/kdelibs/phonon/; revision=651904

sandsmark/phonon-visualization-gsoc,sandsmark/phonon-visualization-gsoc,sandsmark/phonon-visualization-gsoc,sandsmark/phonon-visualization-gsoc