Fixed a possible assert in QGtkStyle
Fixed a possible assert in QGtkStyle

We now set and unset the GTK_HAS_FOCUS flag on the same
painting call only if focus is set instead of resetting it
on each painting call. This is a tiny optimization but also kills
a possible assert on certain versions of Gtk+ (as reported with
Red Hat Enterprise Linux 5).

Task-number: 254614
Reviewed-by: denis

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