When using subsurf (and other modifiers) the edit flags are not
propagated correctly. Currently we assume to read the edit flags
from the original object which is kind off hinding the real issue.

Modifiers use mesh_new_nomain_from_template_ex to create a copy
from an existing mesh. this method is only used by modifiers. So
by placing this we will make sure that editmesh is propagated.

IMO Ideally the draw manager should work fully on the depgraph object and
not check the state of the original object, this will need additional
refactoring and testing.