This breaks weston_output_mode_switch() into 3 functions:
weston_output_mode_set_native()
weston_output_mode_switch_to_temporary()
weston_output_mode_switch_to_native()
Differences from previous behaviour:
SET_NATIVE didn't set current_scale (now it does)
SET_TEMPORARY could set mode and scale independently - now it can't.
Signed-off-by: Derek Foreman <derekf@osg.samsung.com>
Pekka Paalanen <pekka.paalanen@collabora.co.uk>