wayland/surface: Swap 90 and 270 degree transforms
Our internal interpretation is not conform with the Wayland spec,
but is in line with e.g. graphene. Lets just swap the relevant cases
when we go from WL_OUTPUT_TRANSFORM
to META_MONITOR_TRANSFORM
See: https://gitlab.freedesktop.org/wayland/weston/issues/99
This MR make Mutter compatible with the changes in https://gitlab.freedesktop.org/wayland/weston/merge_requests/383
Fixes #1045 (comment 712038)
Edited by Florian Müllner