code: @Override
    public void visit(NodeTraversal traversal, Node node, Node parent) {
      if (node.isCall()) {
        Node name = node.getFirstChild();
        Node argument = name.getNext();
        if (argument == null) {
          return;
        }
  
        // Detect calls to an aliased goog.string.Const.
        if (name.isName() && !name.matchesQualifiedName(CONST_FUNCTION_NAME_COLLAPSED)) {
          Scope scope = traversal.getScope();
          Var var = scope.getVar(name.getString());
          if (var == null) {
            return;
          }
          name = var.getInitialValue();
          if (name == null) {
            return;
          }
        }
  
        if (name.matchesQualifiedName(CONST_FUNCTION_NAME)
            || name.matchesQualifiedName(CONST_FUNCTION_NAME_COLLAPSED)) {
          if (!isSafeValue(traversal.getScope(), argument)) {
            compiler.report(JSError.make(argument, CONST_NOT_STRING_LITERAL_ERROR));
          }
        }
      }
    }
docs: Callback to visit a node and check method call arguments of
  {@code goog.string.Const.from}.
  
  @param traversal The node traversal object that supplies context, such as
  the scope chain to use in name lookups as well as error reporting.
  @param node The node being visited.
  @param parent The parent of the node.