This adds a simple conformance test which sets up a few shader effects
using both the old style with clutter_shader_effect_set_source and the
new style by overriding get_static_shader_source. The effects are then
verified to confirm that they drew the right pixel colour.
https://bugzilla.gnome.org/show_bug.cgi?id=660512
Reviewed-by: Emmanuele Bassi <ebassi@linux.intel.com>
