Try to fix paint issues on windows

Davide complained about a flickr on windows, I think it
has to do with the QPainter now knowing the right
size of it's paint rect. this should fix it.

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/modeldelegates.cpp

@@ -562,6 +562,7 @@ print_part:
 	initStyleOption(&opt, index);
 	opt.text = QString();
 	opt.icon = QIcon();
+	painter->setClipRect(option.rect);
 	qApp->style()->drawControl(QStyle::CE_ItemViewItem, &opt, painter, NULL);
 
 	painter->save();