Respect centered images size
Centered images should be cropped all around if they are bigger than the screen, so we can't limit their sourceSize to the desktop size
Use the provider only for svgs: Image always considers images from image providers as scalable (QQuickPixmap::isScalableImageFormat) which changes the internal calculation of the size, having images being rendered on different sizes depending if they are loaded from package or directly
Edited by Marco Martin