pixman-renderer: move code to draw_view_translated()
pixman-renderer: move code to draw_view_translated()

Move code from draw_view() into a new function draw_view_translated().
This new function is correct only if
view_transformation_is_translation().

The test for view->alpha is moved into draw_view_translated() too, so we
don't need to pass the pixman_op from draw_view(). The non-translation
path is already using PIXMAN_OP_OVER, so it does not care about the
alpha.

v2: Fixed commit message.

Signed-off-by: Pekka Paalanen <0f6ae7001e34c37b02fb2c1c2573ddf8f442136a@collabora.co.uk>
Reviewed-By: Derek Foreman <2f97e0f0bc172406aab8ccd42dab54c95bab8759@osg.samsung.com>
Reviewed-by: Jason Ekstrand <68c46a606457643eab92053c1c05574abb26f861@jlekstrand.net>

eyolfson/weston,udoprog/weston,sir-murray/weston,krezovic/weston,jonnylamb/weston,Tarnyko/weston-xdg_surface_present,Tarnyko/weston-xdg_surface_present,mchalupa/weston,eyolfson/weston,mchalupa/weston,kwm81/weston,kwm81/weston,xorgy/weston,jonnylamb/weston,udoprog/weston,Gnurou/weston,Gnurou/weston,giucam/weston,Fantu/compositor-spice,giucam/weston,xorgy/weston,krezovic/weston,Fantu/compositor-spice,sir-murray/weston,Fantu/compositor-spice