472a434212
Add support for rotated monitors. This is done per logical monitor, as every monitor assigned to a logical monitor must be transformed in the same way. This includes being transformed on the same level; e.g. if the backend does not support transforming any monitor of a logical monitor natively, then all monitors will be transformed using the offscreen intermediate framebuffer. https://bugzilla.gnome.org/show_bug.cgi?id=777732