One of the new fvf types (FVF_MODULATED) allows batching custom shaders that use modulate. The only slight oversight is that there is a special define when MODULATE is used in a custom shader, called MODULATE_USED, that is checked, and if set it does NOT apply final_modulate as part of canvas.glsl.
This MODULATE_USED define wasn't checked when the new FVF was used and modulate was passed in an attribute.
This PR moves the application of the final_modulate into the #ifndef MODULATE_USED section.
c401960634