Rectangle with negative dimensions is not drawn with QSvgGenerator

When drawing a rectangle with negative height/width it doesn't get drawn to SVG. The same rectangle is drawn fine with QPainter.

Steps to reproduce the issue:
1. Run attached test application
2. Click on "Save SVG to" button
3. Compare the QPainter and QSvgGenerator output

Expected outcome:
Also the rectangle with negative height / width is drawn similarly as with QPainter

Actual outcome:
Rectangles with negative height / width are outputted to svg file as is without any normalisation. Therefore they are not visible with e.g. web browsers.