Blender Git Loki

Cleanup: Remove redundant function (and cleanup compiler warnings in the process)

BKE_gpencil_frame_color_duplicate() is no longer needed to perform Grease Pencil's
in-house "COW" operations. It was previously used to create a copy of the palette
datablock being used, and to then reassign all the color pointers. Now that that's
no longer needed, we can just use the standard one.

Note: BKE_gpencil_stroke_duplicate() has now been modified to NOT clear the triangles
array anymore. Instead, since most places that use this will clear/reallocate it
themselves, it's easier to just keep it there, making the COW stuff easier.