code: private static void setDefineInfoNotAssignable(DefineInfo info, NodeTraversal t) {
      info.setNotAssignable(
          format(REASON_DEFINE_NOT_ASSIGNABLE, t.getLineNumber(), t.getSourceName()));
    }
docs: Records the fact that because of the current node in the node traversal, the define can't ever
  be assigned again.
  
  @param info Represents the define variable.
  @param t The current traversal.