Blender Git Loki

Fix T65285: Crash with Object.to_mesh() in certain conditions

Was happening when modifier stack detected that mesh is not deformed
and is not modified and attempted to share result across multiple
objects.

This was introduced in 2f77119.

Now functions which are supposed to return mesh owned by caller will
do so again. Shouldn't be a huge impact on memory print since the
data layers are referenced.