Use pixel coordinates for weston_output.matrix

Previously, weston_output.matrix was in GL coordinates and therefore only
really useful for the GL backend.

This breaks zoom, which will be fixed by the following patch:
	zoom: Use pixels instead of GL coordinates

[Pekka: added a comment to compositor.h, message]
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>
Reviewed-By: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
3 files changed