QGraphicsTextItem font gets incorrectly clipped when a clip rect is set on the painter.

The attached repro and gif shows the issue where text glyphs in a graphics scene gets clipped when another item is moved over them. This is because when moving a graphics item the clip rect is set to avoid repainting more than needed.

I debugged it a bit and found 2 issues in the raster engine that contributed to this, see attached patch for a suggested fix. Not sure if it is the correct thing to do but from my debugging it seemed like the clip rect was always correct, and it only really fails for this case so I just assumed this code needed to be adjusted.