Fix warning on QVector with gcc4.4
Fix warning on QVector with gcc4.4

Use QVectorData whenever possible instead of QVectorTypedData.

It is not safe to convert the shared_null to QVectorTypedData as
different instance of qvector with different type may cast it in the
same function (because everything is inline) and that would break strict
aliasing.

Reviewed-by: Thiago
Reviewed-by: Brad

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