Blender Git Loki

Fix T41703: Blender crashes trying to load character file.

Core of the issue is that pointcache handling in depsgraph were (re-) tagging
for update some objects on hidden layers, when all their dependencies remained
untag.

Since we do not want to update objects on hidden layers, take this data into account
when flushing pointcache.

Investigations and org patch by self, reviews, advices and final patch by sergey, many thanks! :)