code: function(oldName, newName) {
      if (Blockly.Names.equals(oldName, this.getProcedureCall())) {
        this.setFieldValue(newName, 'NAME');
        this.setTooltip(
            (this.outputConnection ? Blockly.Msg.PROCEDURES_CALLRETURN_TOOLTIP :
             Blockly.Msg.PROCEDURES_CALLNORETURN_TOOLTIP)
            .replace('%1', newName));
      }
    }
docs: Notification that a procedure is renaming.
  If the name matches this block's procedure, rename it.
  @param {string} oldName Previous name of procedure.
  @param {string} newName Renamed procedure.
  @this Blockly.Block