[Amarok] Fix a bunch of qwarnings caused by QPainter on nul

[Kevin Funk]

> On Fri, Oct 23, 2009 at 6:31 AM, Mark Kretschmann <kretschmann at kde.org> 
wrote:
> If you set the QT_FATAL_WARNINGS environment variable to 1, Qt's
> runtime warnings and errors will cause a crash (and thus provide a
> backtrace), instead of just printing a text.

Yep, did this. It's pretty hard to fix it otherwise.

-- 
Kevin Funk