message: Add LinkListFriend::get_origin_column
diff: @@ -384,6 +384,12 @@ public:
  {
  list.do_insert(link_ndx, target_row_ndx);
  }
  +
  + static const LinkListColumn& get_origin_column(const LinkView& list)
  + {
  + REALM_ASSERT(list.is_attached());
  + return *list.m_origin_column;
  + }
  };
  } // namespace realm
  