code: function(xmlElement) {
      this.arguments_ = [];
      for (var i = 0, childNode; childNode = xmlElement.childNodes[i]; i++) {
        if (childNode.nodeName.toLowerCase() == 'arg') {
          this.arguments_.push(childNode.getAttribute('name'));
        }
      }
      this.updateParams_();
      Blockly.Procedures.mutateCallers(this);
  
      // Show or hide the statement input.
      this.setStatements_(xmlElement.getAttribute('statements') !== 'false');
    }
docs: Parse XML to restore the argument inputs.
  @param {!Element} xmlElement XML storage element.
  @this Blockly.Block