QRect::normalized() doesn't preserve rect's size

QRect::normalized() in case of negative rectangle's height/width returns rectangle, whose corresponding dimensions are larger by 2px. QRectF::normalized() works as expected.

Example:

#include <QRect>
#include <QDebug>

int main(int argc, char *argv[])
{
    QRect r(QPoint(0,0), QSize(-1,-1));
    qWarning() << "in:" << r << "out:" << r.normalized();
    qWarning() << "in:" << QRectF(r) << "out:" << QRectF(r).normalized();
    return 0;
}

 Output:

in: QRect(0,0 -1x-1) out: QRect(-2,-2 3x3)
in: QRectF(0,0 -1x-1) out: QRectF(-1,-1 1x1)

It looks like this function in such non-correctly working state is quite useless and can be potentially a source of bugs. For example, QPainter's code has it's own implementation of normalized() for correctness, see https://codereview.qt-project.org/173060. It would be nice to fix this behaviour for everyone.

Proposed possible fix is attached (Qt 5.9.3). Maybe It's also a solution for ---QTBUG-22934---, QTBUG-28851 and QTBUG-38653.