code: function getSameColumnCount(currentColumn, prevColumn) {
      var index = 0;
      var len = Math.min(currentColumn.length, prevColumn.length);
  
      for (; index < len; index += 1) {
          if (currentColumn[index].name !== prevColumn[index].name) {
              break;
          }
      }
  
      return index;
  }
docs: Get count of same columns in complex columns
  @param {array} currentColumn - Current column's model
  @param {array} prevColumn - Previous column's model
  @returns {number} Count of same columns
  @ignore