This includes:
- Skip OB_RECALC_TIME tag from object duplicate operator
not sure why it is needed: even if original object was
animated, duplicating it will copy evaluated values.
- Don't tag whole ID for update when updating it after
relations rebuilt. Use the same trickery to detect
whether animation is to be re-evaluated or not as is
done for update flag=0.
- Don't tag datablocks which are expanded for update
of copy-on-write.
- Avoid flush along relation from copy-on-write
operation in action. This will not invalidate any
pointers in the copied datablock since we don't
reference anything in the action.