Do not rely on a draw or dispatch command to do this.
This allows more efficiently testing syntax, in cases where testing the actual
shader functionality is not interesting.
Otherwise we get false in implicit_compatible_data_types() when passing
types that are equal but not convertible according to
convertible_data_type(); e.g. getting:
"Can't implicitly convert from Texture2D<float4> to Texture2D<float4>."
Signed-off-by: Francisco Casas <fcasas@codeweavers.com>
