50b0a3d672
Hoist the duplicated code from the _Optional_payload partial specializations into the _Optional_payload_base base class. * include/std/optional (_Optional_payload_base::_M_copy_assign): New member function to perform non-trivial assignment. (_Optional_payload_base::_M_move_assign): Likewise. (_Optional_payload<T, true, false, true>::operator=) (_Optional_payload<T, true, true, false>::operator=) (_Optional_payload<T, true, false, false>::operator=): Call _M_copy_assign and/or _M_move_assign to do non-trivial assignments. From-SVN: r267761