Each snippet is now given its own function which contains the pre and
post strings. Between these strings the function will chain on to
another function. The generated cogl source is now stored in a
function called cogl_generated_source() which the last snippet will
chain on to. This should make it so that each snippet has its own
namespace for local variables and it can share variables declared in
the pre string in the post string. Hopefully the GLSL compiler will
just inline all of the functions so it shouldn't make much difference
to the compiled output.
Reviewed-by: Robert Bragg <robert@linux.intel.com>
