Unnecessary rounding of QRectF in QCoreGraphicsPaintEngine::drawPixmap

At line #972 in qpaintengine_mac.cpp, the input QRectF is rounded into integer values before converting into a CGRect:

CGRect rect = CGRectMake(qRound(r.x()), qRound(r.y()), qRound(r.width()), qRound(r.height()));

This is causing some positioning error due to the rounding when the transformation calls for scaling like 0.07. The same conversion in QCoreGraphicsPaintEngine::drawImage() does not do the rounding.

The issue causes tiles of images to either overlap or leave space (typically 1 pixel) between them. Using QPainter::drawImage() does not have the same problem. Removing qRound calls in that line fixes the issue.