Blender Git Loki

Hacky WIP code to verify that GPencil-Dopesheet Integration (for modifiers) is working

This code should be replaced, as it currently just duplicates the
modifier-looping logic (bad!). However, this is just a temporary placeholder
needed to get the updateDepsgraph() calls to run at all.

In any case, this would've been easier if I'd done the ob->gpd ==> ob->data
fixes first, since this hack wouldn't be needed.