Fix QPixmap::fromImage() bug for monochrome images on Mac.
Fix QPixmap::fromImage() bug for monochrome images on Mac.

Monochrome images should be converted to black and white, not
transparent and white. Reported on qt-interest.

Task-number: 249175
Reviewed-by: Trond

KDE/qt,igor-sfdc/qt-wk,radekp/qt,radekp/qt,igor-sfdc/qt-wk,radekp/qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,radekp/qt,KDE/qt,igor-sfdc/qt-wk,RLovelett/qt,igor-sfdc/qt-wk,KDE/qt,igor-sfdc/qt-wk,RLovelett/qt,KDE/qt,pruiz/wkhtmltopdf-qt,radekp/qt,radekp/qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,RLovelett/qt,RLovelett/qt,RLovelett/qt,pruiz/wkhtmltopdf-qt,RLovelett/qt,RLovelett/qt,KDE/qt,pruiz/wkhtmltopdf-qt,radekp/qt,RLovelett/qt,RLovelett/qt,radekp/qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,KDE/qt,RLovelett/qt,KDE/qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,radekp/qt,RLovelett/qt,radekp/qt,KDE/qt